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1 |
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2 /* png.h - header file for PNG reference library |
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3 * |
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4 * libpng version 1.5.13 - September 27, 2012 |
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5 * Copyright (c) 1998-2012 Glenn Randers-Pehrson |
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6 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) |
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7 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) |
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8 * |
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9 * This code is released under the libpng license (See LICENSE, below) |
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10 * |
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11 * Authors and maintainers: |
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12 * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat |
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13 * libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger |
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14 * libpng versions 0.97, January 1998, through 1.5.13 - September 27, 2012: Glenn |
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15 * See also "Contributing Authors", below. |
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16 * |
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17 * Note about libpng version numbers: |
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18 * |
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19 * Due to various miscommunications, unforeseen code incompatibilities |
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20 * and occasional factors outside the authors' control, version numbering |
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21 * on the library has not always been consistent and straightforward. |
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22 * The following table summarizes matters since version 0.89c, which was |
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23 * the first widely used release: |
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24 * |
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25 * source png.h png.h shared-lib |
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26 * version string int version |
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27 * ------- ------ ----- ---------- |
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28 * 0.89c "1.0 beta 3" 0.89 89 1.0.89 |
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29 * 0.90 "1.0 beta 4" 0.90 90 0.90 [should have been 2.0.90] |
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30 * 0.95 "1.0 beta 5" 0.95 95 0.95 [should have been 2.0.95] |
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31 * 0.96 "1.0 beta 6" 0.96 96 0.96 [should have been 2.0.96] |
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32 * 0.97b "1.00.97 beta 7" 1.00.97 97 1.0.1 [should have been 2.0.97] |
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33 * 0.97c 0.97 97 2.0.97 |
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34 * 0.98 0.98 98 2.0.98 |
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35 * 0.99 0.99 98 2.0.99 |
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36 * 0.99a-m 0.99 99 2.0.99 |
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37 * 1.00 1.00 100 2.1.0 [100 should be 10000] |
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38 * 1.0.0 (from here on, the 100 2.1.0 [100 should be 10000] |
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39 * 1.0.1 png.h string is 10001 2.1.0 |
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40 * 1.0.1a-e identical to the 10002 from here on, the shared library |
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41 * 1.0.2 source version) 10002 is 2.V where V is the source code |
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42 * 1.0.2a-b 10003 version, except as noted. |
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43 * 1.0.3 10003 |
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44 * 1.0.3a-d 10004 |
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45 * 1.0.4 10004 |
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46 * 1.0.4a-f 10005 |
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47 * 1.0.5 (+ 2 patches) 10005 |
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48 * 1.0.5a-d 10006 |
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49 * 1.0.5e-r 10100 (not source compatible) |
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50 * 1.0.5s-v 10006 (not binary compatible) |
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51 * 1.0.6 (+ 3 patches) 10006 (still binary incompatible) |
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52 * 1.0.6d-f 10007 (still binary incompatible) |
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53 * 1.0.6g 10007 |
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54 * 1.0.6h 10007 10.6h (testing xy.z so-numbering) |
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55 * 1.0.6i 10007 10.6i |
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56 * 1.0.6j 10007 2.1.0.6j (incompatible with 1.0.0) |
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57 * 1.0.7beta11-14 DLLNUM 10007 2.1.0.7beta11-14 (binary compatible) |
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58 * 1.0.7beta15-18 1 10007 2.1.0.7beta15-18 (binary compatible) |
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59 * 1.0.7rc1-2 1 10007 2.1.0.7rc1-2 (binary compatible) |
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60 * 1.0.7 1 10007 (still compatible) |
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61 * 1.0.8beta1-4 1 10008 2.1.0.8beta1-4 |
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62 * 1.0.8rc1 1 10008 2.1.0.8rc1 |
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63 * 1.0.8 1 10008 2.1.0.8 |
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64 * 1.0.9beta1-6 1 10009 2.1.0.9beta1-6 |
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65 * 1.0.9rc1 1 10009 2.1.0.9rc1 |
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66 * 1.0.9beta7-10 1 10009 2.1.0.9beta7-10 |
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67 * 1.0.9rc2 1 10009 2.1.0.9rc2 |
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68 * 1.0.9 1 10009 2.1.0.9 |
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69 * 1.0.10beta1 1 10010 2.1.0.10beta1 |
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70 * 1.0.10rc1 1 10010 2.1.0.10rc1 |
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71 * 1.0.10 1 10010 2.1.0.10 |
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72 * 1.0.11beta1-3 1 10011 2.1.0.11beta1-3 |
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73 * 1.0.11rc1 1 10011 2.1.0.11rc1 |
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74 * 1.0.11 1 10011 2.1.0.11 |
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75 * 1.0.12beta1-2 2 10012 2.1.0.12beta1-2 |
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76 * 1.0.12rc1 2 10012 2.1.0.12rc1 |
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77 * 1.0.12 2 10012 2.1.0.12 |
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78 * 1.1.0a-f - 10100 2.1.1.0a-f (branch abandoned) |
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79 * 1.2.0beta1-2 2 10200 2.1.2.0beta1-2 |
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80 * 1.2.0beta3-5 3 10200 3.1.2.0beta3-5 |
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81 * 1.2.0rc1 3 10200 3.1.2.0rc1 |
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82 * 1.2.0 3 10200 3.1.2.0 |
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83 * 1.2.1beta1-4 3 10201 3.1.2.1beta1-4 |
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84 * 1.2.1rc1-2 3 10201 3.1.2.1rc1-2 |
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85 * 1.2.1 3 10201 3.1.2.1 |
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86 * 1.2.2beta1-6 12 10202 12.so.0.1.2.2beta1-6 |
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87 * 1.0.13beta1 10 10013 10.so.0.1.0.13beta1 |
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88 * 1.0.13rc1 10 10013 10.so.0.1.0.13rc1 |
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89 * 1.2.2rc1 12 10202 12.so.0.1.2.2rc1 |
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90 * 1.0.13 10 10013 10.so.0.1.0.13 |
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91 * 1.2.2 12 10202 12.so.0.1.2.2 |
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92 * 1.2.3rc1-6 12 10203 12.so.0.1.2.3rc1-6 |
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93 * 1.2.3 12 10203 12.so.0.1.2.3 |
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94 * 1.2.4beta1-3 13 10204 12.so.0.1.2.4beta1-3 |
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95 * 1.0.14rc1 13 10014 10.so.0.1.0.14rc1 |
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96 * 1.2.4rc1 13 10204 12.so.0.1.2.4rc1 |
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97 * 1.0.14 10 10014 10.so.0.1.0.14 |
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98 * 1.2.4 13 10204 12.so.0.1.2.4 |
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99 * 1.2.5beta1-2 13 10205 12.so.0.1.2.5beta1-2 |
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100 * 1.0.15rc1-3 10 10015 10.so.0.1.0.15rc1-3 |
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101 * 1.2.5rc1-3 13 10205 12.so.0.1.2.5rc1-3 |
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102 * 1.0.15 10 10015 10.so.0.1.0.15 |
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103 * 1.2.5 13 10205 12.so.0.1.2.5 |
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104 * 1.2.6beta1-4 13 10206 12.so.0.1.2.6beta1-4 |
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105 * 1.0.16 10 10016 10.so.0.1.0.16 |
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106 * 1.2.6 13 10206 12.so.0.1.2.6 |
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107 * 1.2.7beta1-2 13 10207 12.so.0.1.2.7beta1-2 |
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108 * 1.0.17rc1 10 10017 12.so.0.1.0.17rc1 |
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109 * 1.2.7rc1 13 10207 12.so.0.1.2.7rc1 |
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110 * 1.0.17 10 10017 12.so.0.1.0.17 |
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111 * 1.2.7 13 10207 12.so.0.1.2.7 |
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112 * 1.2.8beta1-5 13 10208 12.so.0.1.2.8beta1-5 |
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113 * 1.0.18rc1-5 10 10018 12.so.0.1.0.18rc1-5 |
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114 * 1.2.8rc1-5 13 10208 12.so.0.1.2.8rc1-5 |
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115 * 1.0.18 10 10018 12.so.0.1.0.18 |
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116 * 1.2.8 13 10208 12.so.0.1.2.8 |
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117 * 1.2.9beta1-3 13 10209 12.so.0.1.2.9beta1-3 |
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118 * 1.2.9beta4-11 13 10209 12.so.0.9[.0] |
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119 * 1.2.9rc1 13 10209 12.so.0.9[.0] |
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120 * 1.2.9 13 10209 12.so.0.9[.0] |
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121 * 1.2.10beta1-7 13 10210 12.so.0.10[.0] |
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122 * 1.2.10rc1-2 13 10210 12.so.0.10[.0] |
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123 * 1.2.10 13 10210 12.so.0.10[.0] |
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124 * 1.4.0beta1-5 14 10400 14.so.0.0[.0] |
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125 * 1.2.11beta1-4 13 10211 12.so.0.11[.0] |
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126 * 1.4.0beta7-8 14 10400 14.so.0.0[.0] |
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127 * 1.2.11 13 10211 12.so.0.11[.0] |
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128 * 1.2.12 13 10212 12.so.0.12[.0] |
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129 * 1.4.0beta9-14 14 10400 14.so.0.0[.0] |
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130 * 1.2.13 13 10213 12.so.0.13[.0] |
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131 * 1.4.0beta15-36 14 10400 14.so.0.0[.0] |
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132 * 1.4.0beta37-87 14 10400 14.so.14.0[.0] |
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133 * 1.4.0rc01 14 10400 14.so.14.0[.0] |
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134 * 1.4.0beta88-109 14 10400 14.so.14.0[.0] |
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135 * 1.4.0rc02-08 14 10400 14.so.14.0[.0] |
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136 * 1.4.0 14 10400 14.so.14.0[.0] |
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137 * 1.4.1beta01-03 14 10401 14.so.14.1[.0] |
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138 * 1.4.1rc01 14 10401 14.so.14.1[.0] |
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139 * 1.4.1beta04-12 14 10401 14.so.14.1[.0] |
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140 * 1.4.1 14 10401 14.so.14.1[.0] |
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141 * 1.4.2 14 10402 14.so.14.2[.0] |
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142 * 1.4.3 14 10403 14.so.14.3[.0] |
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143 * 1.4.4 14 10404 14.so.14.4[.0] |
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144 * 1.5.0beta01-58 15 10500 15.so.15.0[.0] |
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145 * 1.5.0rc01-07 15 10500 15.so.15.0[.0] |
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146 * 1.5.0 15 10500 15.so.15.0[.0] |
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147 * 1.5.1beta01-11 15 10501 15.so.15.1[.0] |
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148 * 1.5.1rc01-02 15 10501 15.so.15.1[.0] |
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149 * 1.5.1 15 10501 15.so.15.1[.0] |
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150 * 1.5.2beta01-03 15 10502 15.so.15.2[.0] |
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151 * 1.5.2rc01-03 15 10502 15.so.15.2[.0] |
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152 * 1.5.2 15 10502 15.so.15.2[.0] |
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153 * 1.5.3beta01-10 15 10503 15.so.15.3[.0] |
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154 * 1.5.3rc01-02 15 10503 15.so.15.3[.0] |
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155 * 1.5.3beta11 15 10503 15.so.15.3[.0] |
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156 * 1.5.3 [omitted] |
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157 * 1.5.4beta01-08 15 10504 15.so.15.4[.0] |
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158 * 1.5.4rc01 15 10504 15.so.15.4[.0] |
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159 * 1.5.4 15 10504 15.so.15.4[.0] |
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160 * 1.5.5beta01-08 15 10505 15.so.15.5[.0] |
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161 * 1.5.5rc01 15 10505 15.so.15.5[.0] |
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162 * 1.5.5 15 10505 15.so.15.5[.0] |
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163 * 1.5.6beta01-07 15 10506 15.so.15.6[.0] |
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164 * 1.5.6rc01-03 15 10506 15.so.15.6[.0] |
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165 * 1.5.6 15 10506 15.so.15.6[.0] |
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166 * 1.5.7beta01-05 15 10507 15.so.15.7[.0] |
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167 * 1.5.7rc01-03 15 10507 15.so.15.7[.0] |
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168 * 1.5.7 15 10507 15.so.15.7[.0] |
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169 * 1.5.8beta01 15 10508 15.so.15.8[.0] |
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170 * 1.5.8rc01 15 10508 15.so.15.8[.0] |
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171 * 1.5.8 15 10508 15.so.15.8[.0] |
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172 * 1.5.9beta01-02 15 10509 15.so.15.9[.0] |
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173 * 1.5.9rc01 15 10509 15.so.15.9[.0] |
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174 * 1.5.9 15 10509 15.so.15.9[.0] |
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175 * 1.5.10beta01-05 15 10510 15.so.15.10[.0] |
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176 * 1.5.10 15 10510 15.so.15.10[.0] |
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177 * 1.5.11beta01 15 10511 15.so.15.11[.0] |
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178 * 1.5.11rc01-05 15 10511 15.so.15.11[.0] |
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179 * 1.5.11 15 10511 15.so.15.11[.0] |
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180 * 1.5.12 15 10512 15.so.15.12[.0] |
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181 * 1.5.13beta01-02 15 10513 15.so.15.13[.0] |
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182 * 1.5.13rc01 15 10513 15.so.15.13[.0] |
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183 * 1.5.13 15 10513 15.so.15.13[.0] |
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184 * |
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185 * Henceforth the source version will match the shared-library major |
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186 * and minor numbers; the shared-library major version number will be |
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187 * used for changes in backward compatibility, as it is intended. The |
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188 * PNG_LIBPNG_VER macro, which is not used within libpng but is available |
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189 * for applications, is an unsigned integer of the form xyyzz corresponding |
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190 * to the source version x.y.z (leading zeros in y and z). Beta versions |
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191 * were given the previous public release number plus a letter, until |
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192 * version 1.0.6j; from then on they were given the upcoming public |
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193 * release number plus "betaNN" or "rcNN". |
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194 * |
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195 * Binary incompatibility exists only when applications make direct access |
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196 * to the info_ptr or png_ptr members through png.h, and the compiled |
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197 * application is loaded with a different version of the library. |
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198 * |
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199 * DLLNUM will change each time there are forward or backward changes |
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200 * in binary compatibility (e.g., when a new feature is added). |
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201 * |
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202 * See libpng-manual.txt or libpng.3 for more information. The PNG |
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203 * specification is available as a W3C Recommendation and as an ISO |
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204 * Specification, <http://www.w3.org/TR/2003/REC-PNG-20031110/ |
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205 */ |
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206 |
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207 /* |
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208 * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE: |
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209 * |
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210 * If you modify libpng you may insert additional notices immediately following |
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211 * this sentence. |
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212 * |
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213 * This code is released under the libpng license. |
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214 * |
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215 * libpng versions 1.2.6, August 15, 2004, through 1.5.13, September 27, 2012, are |
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216 * Copyright (c) 2004, 2006-2012 Glenn Randers-Pehrson, and are |
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217 * distributed according to the same disclaimer and license as libpng-1.2.5 |
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218 * with the following individual added to the list of Contributing Authors: |
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219 * |
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220 * Cosmin Truta |
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221 * |
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222 * libpng versions 1.0.7, July 1, 2000, through 1.2.5, October 3, 2002, are |
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223 * Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are |
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224 * distributed according to the same disclaimer and license as libpng-1.0.6 |
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225 * with the following individuals added to the list of Contributing Authors: |
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226 * |
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227 * Simon-Pierre Cadieux |
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228 * Eric S. Raymond |
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229 * Gilles Vollant |
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230 * |
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231 * and with the following additions to the disclaimer: |
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232 * |
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233 * There is no warranty against interference with your enjoyment of the |
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234 * library or against infringement. There is no warranty that our |
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235 * efforts or the library will fulfill any of your particular purposes |
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236 * or needs. This library is provided with all faults, and the entire |
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237 * risk of satisfactory quality, performance, accuracy, and effort is with |
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238 * the user. |
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239 * |
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240 * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are |
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241 * Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson, and are |
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242 * distributed according to the same disclaimer and license as libpng-0.96, |
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243 * with the following individuals added to the list of Contributing Authors: |
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244 * |
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245 * Tom Lane |
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246 * Glenn Randers-Pehrson |
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247 * Willem van Schaik |
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248 * |
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249 * libpng versions 0.89, June 1996, through 0.96, May 1997, are |
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250 * Copyright (c) 1996, 1997 Andreas Dilger |
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251 * Distributed according to the same disclaimer and license as libpng-0.88, |
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252 * with the following individuals added to the list of Contributing Authors: |
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253 * |
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254 * John Bowler |
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255 * Kevin Bracey |
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256 * Sam Bushell |
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257 * Magnus Holmgren |
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258 * Greg Roelofs |
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259 * Tom Tanner |
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260 * |
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261 * libpng versions 0.5, May 1995, through 0.88, January 1996, are |
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262 * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc. |
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263 * |
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264 * For the purposes of this copyright and license, "Contributing Authors" |
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265 * is defined as the following set of individuals: |
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266 * |
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267 * Andreas Dilger |
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268 * Dave Martindale |
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269 * Guy Eric Schalnat |
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270 * Paul Schmidt |
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271 * Tim Wegner |
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272 * |
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273 * The PNG Reference Library is supplied "AS IS". The Contributing Authors |
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274 * and Group 42, Inc. disclaim all warranties, expressed or implied, |
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275 * including, without limitation, the warranties of merchantability and of |
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276 * fitness for any purpose. The Contributing Authors and Group 42, Inc. |
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277 * assume no liability for direct, indirect, incidental, special, exemplary, |
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278 * or consequential damages, which may result from the use of the PNG |
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279 * Reference Library, even if advised of the possibility of such damage. |
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280 * |
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281 * Permission is hereby granted to use, copy, modify, and distribute this |
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282 * source code, or portions hereof, for any purpose, without fee, subject |
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283 * to the following restrictions: |
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284 * |
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285 * 1. The origin of this source code must not be misrepresented. |
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286 * |
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287 * 2. Altered versions must be plainly marked as such and must not |
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288 * be misrepresented as being the original source. |
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289 * |
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290 * 3. This Copyright notice may not be removed or altered from |
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291 * any source or altered source distribution. |
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292 * |
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293 * The Contributing Authors and Group 42, Inc. specifically permit, without |
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294 * fee, and encourage the use of this source code as a component to |
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295 * supporting the PNG file format in commercial products. If you use this |
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296 * source code in a product, acknowledgment is not required but would be |
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297 * appreciated. |
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298 */ |
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299 |
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300 /* |
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301 * A "png_get_copyright" function is available, for convenient use in "about" |
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302 * boxes and the like: |
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303 * |
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304 * printf("%s", png_get_copyright(NULL)); |
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305 * |
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306 * Also, the PNG logo (in PNG format, of course) is supplied in the |
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307 * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31). |
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308 */ |
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309 |
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310 /* |
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311 * Libpng is OSI Certified Open Source Software. OSI Certified is a |
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312 * certification mark of the Open Source Initiative. |
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313 */ |
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314 |
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315 /* |
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316 * The contributing authors would like to thank all those who helped |
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317 * with testing, bug fixes, and patience. This wouldn't have been |
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318 * possible without all of you. |
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319 * |
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320 * Thanks to Frank J. T. Wojcik for helping with the documentation. |
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321 */ |
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322 |
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323 /* |
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324 * Y2K compliance in libpng: |
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325 * ========================= |
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326 * |
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327 * September 27, 2012 |
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328 * |
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329 * Since the PNG Development group is an ad-hoc body, we can't make |
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330 * an official declaration. |
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331 * |
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332 * This is your unofficial assurance that libpng from version 0.71 and |
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333 * upward through 1.5.13 are Y2K compliant. It is my belief that |
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334 * earlier versions were also Y2K compliant. |
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335 * |
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336 * Libpng only has two year fields. One is a 2-byte unsigned integer |
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337 * that will hold years up to 65535. The other holds the date in text |
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338 * format, and will hold years up to 9999. |
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339 * |
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340 * The integer is |
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341 * "png_uint_16 year" in png_time_struct. |
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342 * |
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343 * The string is |
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344 * "char time_buffer[29]" in png_struct. This will be no |
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345 * longer used in libpng-1.6.0 and will be removed from libpng-1.7.0. |
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346 * |
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347 * There are seven time-related functions: |
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348 * png.c: png_convert_to_rfc_1123() in png.c |
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349 * (formerly png_convert_to_rfc_1152() in error) |
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350 * png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c |
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351 * png_convert_from_time_t() in pngwrite.c |
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352 * png_get_tIME() in pngget.c |
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353 * png_handle_tIME() in pngrutil.c, called in pngread.c |
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354 * png_set_tIME() in pngset.c |
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355 * png_write_tIME() in pngwutil.c, called in pngwrite.c |
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356 * |
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357 * All handle dates properly in a Y2K environment. The |
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358 * png_convert_from_time_t() function calls gmtime() to convert from system |
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359 * clock time, which returns (year - 1900), which we properly convert to |
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360 * the full 4-digit year. There is a possibility that applications using |
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361 * libpng are not passing 4-digit years into the png_convert_to_rfc_1123() |
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362 * function, or that they are incorrectly passing only a 2-digit year |
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363 * instead of "year - 1900" into the png_convert_from_struct_tm() function, |
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364 * but this is not under our control. The libpng documentation has always |
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365 * stated that it works with 4-digit years, and the APIs have been |
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366 * documented as such. |
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367 * |
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368 * The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned |
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369 * integer to hold the year, and can hold years as large as 65535. |
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370 * |
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371 * zlib, upon which libpng depends, is also Y2K compliant. It contains |
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372 * no date-related code. |
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373 * |
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374 * Glenn Randers-Pehrson |
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375 * libpng maintainer |
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376 * PNG Development Group |
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377 */ |
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378 |
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379 #ifndef PNG_H |
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380 #define PNG_H |
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381 |
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382 /* This is not the place to learn how to use libpng. The file libpng-manual.txt |
|
383 * describes how to use libpng, and the file example.c summarizes it |
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384 * with some code on which to build. This file is useful for looking |
|
385 * at the actual function definitions and structure components. |
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386 * |
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387 * If you just need to read a PNG file and don't want to read the documentation |
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388 * skip to the end of this file and read the section entitled 'simplified API'. |
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389 */ |
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390 |
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391 /* Version information for png.h - this should match the version in png.c */ |
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392 #define PNG_LIBPNG_VER_STRING "1.5.13" |
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393 #define PNG_HEADER_VERSION_STRING \ |
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394 " libpng version 1.5.13 - September 27, 2012\n" |
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395 |
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396 #define PNG_LIBPNG_VER_SONUM 15 |
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397 #define PNG_LIBPNG_VER_DLLNUM 15 |
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398 |
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399 /* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */ |
|
400 #define PNG_LIBPNG_VER_MAJOR 1 |
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401 #define PNG_LIBPNG_VER_MINOR 5 |
|
402 #define PNG_LIBPNG_VER_RELEASE 13 |
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403 |
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404 /* This should match the numeric part of the final component of |
|
405 * PNG_LIBPNG_VER_STRING, omitting any leading zero: |
|
406 */ |
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407 |
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408 #define PNG_LIBPNG_VER_BUILD 0 |
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409 |
|
410 /* Release Status */ |
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411 #define PNG_LIBPNG_BUILD_ALPHA 1 |
|
412 #define PNG_LIBPNG_BUILD_BETA 2 |
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413 #define PNG_LIBPNG_BUILD_RC 3 |
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414 #define PNG_LIBPNG_BUILD_STABLE 4 |
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415 #define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7 |
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416 |
|
417 /* Release-Specific Flags */ |
|
418 #define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with |
|
419 PNG_LIBPNG_BUILD_STABLE only */ |
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420 #define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with |
|
421 PNG_LIBPNG_BUILD_SPECIAL */ |
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422 #define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with |
|
423 PNG_LIBPNG_BUILD_PRIVATE */ |
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424 |
|
425 #define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE |
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426 |
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427 /* Careful here. At one time, Guy wanted to use 082, but that would be octal. |
|
428 * We must not include leading zeros. |
|
429 * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only |
|
430 * version 1.0.0 was mis-numbered 100 instead of 10000). From |
|
431 * version 1.0.1 it's xxyyzz, where x=major, y=minor, z=release |
|
432 */ |
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433 #define PNG_LIBPNG_VER 10513 /* 1.5.13 */ |
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434 |
|
435 /* Library configuration: these options cannot be changed after |
|
436 * the library has been built. |
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437 */ |
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438 #ifndef PNGLCONF_H |
|
439 /* If pnglibconf.h is missing, you can |
|
440 * copy scripts/pnglibconf.h.prebuilt to pnglibconf.h |
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441 */ |
|
442 # include "pnglibconf.h" |
|
443 #endif |
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444 |
|
445 #ifndef PNG_VERSION_INFO_ONLY |
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446 # ifndef PNG_BUILDING_SYMBOL_TABLE |
|
447 /* |
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448 * Standard header files (not needed for the version info or while |
|
449 * building symbol table -- see scripts/pnglibconf.dfa) |
|
450 */ |
|
451 # ifdef PNG_SETJMP_SUPPORTED |
|
452 # include <setjmp.h> |
|
453 # endif |
|
454 |
|
455 /* Need the time information for converting tIME chunks, it |
|
456 * defines struct tm: |
|
457 */ |
|
458 # ifdef PNG_CONVERT_tIME_SUPPORTED |
|
459 /* "time.h" functions are not supported on all operating systems */ |
|
460 # include <time.h> |
|
461 # endif |
|
462 # endif |
|
463 |
|
464 /* Machine specific configuration. */ |
|
465 # include "pngconf.h" |
|
466 #endif |
|
467 |
|
468 /* |
|
469 * Added at libpng-1.2.8 |
|
470 * |
|
471 * Ref MSDN: Private as priority over Special |
|
472 * VS_FF_PRIVATEBUILD File *was not* built using standard release |
|
473 * procedures. If this value is given, the StringFileInfo block must |
|
474 * contain a PrivateBuild string. |
|
475 * |
|
476 * VS_FF_SPECIALBUILD File *was* built by the original company using |
|
477 * standard release procedures but is a variation of the standard |
|
478 * file of the same version number. If this value is given, the |
|
479 * StringFileInfo block must contain a SpecialBuild string. |
|
480 */ |
|
481 |
|
482 #ifdef PNG_USER_PRIVATEBUILD /* From pnglibconf.h */ |
|
483 # define PNG_LIBPNG_BUILD_TYPE \ |
|
484 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE) |
|
485 #else |
|
486 # ifdef PNG_LIBPNG_SPECIALBUILD |
|
487 # define PNG_LIBPNG_BUILD_TYPE \ |
|
488 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL) |
|
489 # else |
|
490 # define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE) |
|
491 # endif |
|
492 #endif |
|
493 |
|
494 #ifndef PNG_VERSION_INFO_ONLY |
|
495 |
|
496 /* Inhibit C++ name-mangling for libpng functions but not for system calls. */ |
|
497 #ifdef __cplusplus |
|
498 extern "C" { |
|
499 #endif /* __cplusplus */ |
|
500 |
|
501 /* Version information for C files, stored in png.c. This had better match |
|
502 * the version above. |
|
503 */ |
|
504 #define png_libpng_ver png_get_header_ver(NULL) |
|
505 |
|
506 /* This file is arranged in several sections: |
|
507 * |
|
508 * 1. Any configuration options that can be specified by for the application |
|
509 * code when it is built. (Build time configuration is in pnglibconf.h) |
|
510 * 2. Type definitions (base types are defined in pngconf.h), structure |
|
511 * definitions. |
|
512 * 3. Exported library functions. |
|
513 * |
|
514 * The library source code has additional files (principally pngpriv.h) that |
|
515 * allow configuration of the library. |
|
516 */ |
|
517 /* Section 1: run time configuration |
|
518 * See pnglibconf.h for build time configuration |
|
519 * |
|
520 * Run time configuration allows the application to choose between |
|
521 * implementations of certain arithmetic APIs. The default is set |
|
522 * at build time and recorded in pnglibconf.h, but it is safe to |
|
523 * override these (and only these) settings. Note that this won't |
|
524 * change what the library does, only application code, and the |
|
525 * settings can (and probably should) be made on a per-file basis |
|
526 * by setting the #defines before including png.h |
|
527 * |
|
528 * Use macros to read integers from PNG data or use the exported |
|
529 * functions? |
|
530 * PNG_USE_READ_MACROS: use the macros (see below) Note that |
|
531 * the macros evaluate their argument multiple times. |
|
532 * PNG_NO_USE_READ_MACROS: call the relevant library function. |
|
533 * |
|
534 * Use the alternative algorithm for compositing alpha samples that |
|
535 * does not use division? |
|
536 * PNG_READ_COMPOSITE_NODIV_SUPPORTED: use the 'no division' |
|
537 * algorithm. |
|
538 * PNG_NO_READ_COMPOSITE_NODIV: use the 'division' algorithm. |
|
539 * |
|
540 * How to handle benign errors if PNG_ALLOW_BENIGN_ERRORS is |
|
541 * false? |
|
542 * PNG_ALLOW_BENIGN_ERRORS: map calls to the benign error |
|
543 * APIs to png_warning. |
|
544 * Otherwise the calls are mapped to png_error. |
|
545 */ |
|
546 |
|
547 /* Section 2: type definitions, including structures and compile time |
|
548 * constants. |
|
549 * See pngconf.h for base types that vary by machine/system |
|
550 */ |
|
551 |
|
552 /* This triggers a compiler error in png.c, if png.c and png.h |
|
553 * do not agree upon the version number. |
|
554 */ |
|
555 typedef char* png_libpng_version_1_5_13; |
|
556 |
|
557 /* Three color definitions. The order of the red, green, and blue, (and the |
|
558 * exact size) is not important, although the size of the fields need to |
|
559 * be png_byte or png_uint_16 (as defined below). |
|
560 */ |
|
561 typedef struct png_color_struct |
|
562 { |
|
563 png_byte red; |
|
564 png_byte green; |
|
565 png_byte blue; |
|
566 } png_color; |
|
567 typedef png_color FAR * png_colorp; |
|
568 typedef PNG_CONST png_color FAR * png_const_colorp; |
|
569 typedef png_color FAR * FAR * png_colorpp; |
|
570 |
|
571 typedef struct png_color_16_struct |
|
572 { |
|
573 png_byte index; /* used for palette files */ |
|
574 png_uint_16 red; /* for use in red green blue files */ |
|
575 png_uint_16 green; |
|
576 png_uint_16 blue; |
|
577 png_uint_16 gray; /* for use in grayscale files */ |
|
578 } png_color_16; |
|
579 typedef png_color_16 FAR * png_color_16p; |
|
580 typedef PNG_CONST png_color_16 FAR * png_const_color_16p; |
|
581 typedef png_color_16 FAR * FAR * png_color_16pp; |
|
582 |
|
583 typedef struct png_color_8_struct |
|
584 { |
|
585 png_byte red; /* for use in red green blue files */ |
|
586 png_byte green; |
|
587 png_byte blue; |
|
588 png_byte gray; /* for use in grayscale files */ |
|
589 png_byte alpha; /* for alpha channel files */ |
|
590 } png_color_8; |
|
591 typedef png_color_8 FAR * png_color_8p; |
|
592 typedef PNG_CONST png_color_8 FAR * png_const_color_8p; |
|
593 typedef png_color_8 FAR * FAR * png_color_8pp; |
|
594 |
|
595 /* |
|
596 * The following two structures are used for the in-core representation |
|
597 * of sPLT chunks. |
|
598 */ |
|
599 typedef struct png_sPLT_entry_struct |
|
600 { |
|
601 png_uint_16 red; |
|
602 png_uint_16 green; |
|
603 png_uint_16 blue; |
|
604 png_uint_16 alpha; |
|
605 png_uint_16 frequency; |
|
606 } png_sPLT_entry; |
|
607 typedef png_sPLT_entry FAR * png_sPLT_entryp; |
|
608 typedef PNG_CONST png_sPLT_entry FAR * png_const_sPLT_entryp; |
|
609 typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp; |
|
610 |
|
611 /* When the depth of the sPLT palette is 8 bits, the color and alpha samples |
|
612 * occupy the LSB of their respective members, and the MSB of each member |
|
613 * is zero-filled. The frequency member always occupies the full 16 bits. |
|
614 */ |
|
615 |
|
616 typedef struct png_sPLT_struct |
|
617 { |
|
618 png_charp name; /* palette name */ |
|
619 png_byte depth; /* depth of palette samples */ |
|
620 png_sPLT_entryp entries; /* palette entries */ |
|
621 png_int_32 nentries; /* number of palette entries */ |
|
622 } png_sPLT_t; |
|
623 typedef png_sPLT_t FAR * png_sPLT_tp; |
|
624 typedef PNG_CONST png_sPLT_t FAR * png_const_sPLT_tp; |
|
625 typedef png_sPLT_t FAR * FAR * png_sPLT_tpp; |
|
626 |
|
627 #ifdef PNG_TEXT_SUPPORTED |
|
628 /* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file, |
|
629 * and whether that contents is compressed or not. The "key" field |
|
630 * points to a regular zero-terminated C string. The "text" fields can be a |
|
631 * regular C string, an empty string, or a NULL pointer. |
|
632 * However, the structure returned by png_get_text() will always contain |
|
633 * the "text" field as a regular zero-terminated C string (possibly |
|
634 * empty), never a NULL pointer, so it can be safely used in printf() and |
|
635 * other string-handling functions. Note that the "itxt_length", "lang", and |
|
636 * "lang_key" members of the structure only exist when the library is built |
|
637 * with iTXt chunk support. Prior to libpng-1.4.0 the library was built by |
|
638 * default without iTXt support. Also note that when iTXt *is* supported, |
|
639 * the "lang" and "lang_key" fields contain NULL pointers when the |
|
640 * "compression" field contains * PNG_TEXT_COMPRESSION_NONE or |
|
641 * PNG_TEXT_COMPRESSION_zTXt. Note that the "compression value" is not the |
|
642 * same as what appears in the PNG tEXt/zTXt/iTXt chunk's "compression flag" |
|
643 * which is always 0 or 1, or its "compression method" which is always 0. |
|
644 */ |
|
645 typedef struct png_text_struct |
|
646 { |
|
647 int compression; /* compression value: |
|
648 -1: tEXt, none |
|
649 0: zTXt, deflate |
|
650 1: iTXt, none |
|
651 2: iTXt, deflate */ |
|
652 png_charp key; /* keyword, 1-79 character description of "text" */ |
|
653 png_charp text; /* comment, may be an empty string (ie "") |
|
654 or a NULL pointer */ |
|
655 png_size_t text_length; /* length of the text string */ |
|
656 png_size_t itxt_length; /* length of the itxt string */ |
|
657 png_charp lang; /* language code, 0-79 characters |
|
658 or a NULL pointer */ |
|
659 png_charp lang_key; /* keyword translated UTF-8 string, 0 or more |
|
660 chars or a NULL pointer */ |
|
661 } png_text; |
|
662 typedef png_text FAR * png_textp; |
|
663 typedef PNG_CONST png_text FAR * png_const_textp; |
|
664 typedef png_text FAR * FAR * png_textpp; |
|
665 #endif |
|
666 |
|
667 /* Supported compression types for text in PNG files (tEXt, and zTXt). |
|
668 * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */ |
|
669 #define PNG_TEXT_COMPRESSION_NONE_WR -3 |
|
670 #define PNG_TEXT_COMPRESSION_zTXt_WR -2 |
|
671 #define PNG_TEXT_COMPRESSION_NONE -1 |
|
672 #define PNG_TEXT_COMPRESSION_zTXt 0 |
|
673 #define PNG_ITXT_COMPRESSION_NONE 1 |
|
674 #define PNG_ITXT_COMPRESSION_zTXt 2 |
|
675 #define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */ |
|
676 |
|
677 /* png_time is a way to hold the time in an machine independent way. |
|
678 * Two conversions are provided, both from time_t and struct tm. There |
|
679 * is no portable way to convert to either of these structures, as far |
|
680 * as I know. If you know of a portable way, send it to me. As a side |
|
681 * note - PNG has always been Year 2000 compliant! |
|
682 */ |
|
683 typedef struct png_time_struct |
|
684 { |
|
685 png_uint_16 year; /* full year, as in, 1995 */ |
|
686 png_byte month; /* month of year, 1 - 12 */ |
|
687 png_byte day; /* day of month, 1 - 31 */ |
|
688 png_byte hour; /* hour of day, 0 - 23 */ |
|
689 png_byte minute; /* minute of hour, 0 - 59 */ |
|
690 png_byte second; /* second of minute, 0 - 60 (for leap seconds) */ |
|
691 } png_time; |
|
692 typedef png_time FAR * png_timep; |
|
693 typedef PNG_CONST png_time FAR * png_const_timep; |
|
694 typedef png_time FAR * FAR * png_timepp; |
|
695 |
|
696 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED) || \ |
|
697 defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED) |
|
698 /* png_unknown_chunk is a structure to hold queued chunks for which there is |
|
699 * no specific support. The idea is that we can use this to queue |
|
700 * up private chunks for output even though the library doesn't actually |
|
701 * know about their semantics. |
|
702 */ |
|
703 typedef struct png_unknown_chunk_t |
|
704 { |
|
705 png_byte name[5]; |
|
706 png_byte *data; |
|
707 png_size_t size; |
|
708 |
|
709 /* libpng-using applications should NOT directly modify this byte. */ |
|
710 png_byte location; /* mode of operation at read time */ |
|
711 } |
|
712 |
|
713 |
|
714 png_unknown_chunk; |
|
715 typedef png_unknown_chunk FAR * png_unknown_chunkp; |
|
716 typedef PNG_CONST png_unknown_chunk FAR * png_const_unknown_chunkp; |
|
717 typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp; |
|
718 #endif |
|
719 |
|
720 /* Values for the unknown chunk location byte */ |
|
721 |
|
722 #define PNG_HAVE_IHDR 0x01 |
|
723 #define PNG_HAVE_PLTE 0x02 |
|
724 #define PNG_AFTER_IDAT 0x08 |
|
725 |
|
726 /* The complete definition of png_info has, as of libpng-1.5.0, |
|
727 * been moved into a separate header file that is not accessible to |
|
728 * applications. Read libpng-manual.txt or libpng.3 for more info. |
|
729 */ |
|
730 typedef struct png_info_def png_info; |
|
731 typedef png_info FAR * png_infop; |
|
732 typedef PNG_CONST png_info FAR * png_const_infop; |
|
733 typedef png_info FAR * FAR * png_infopp; |
|
734 |
|
735 /* Maximum positive integer used in PNG is (2^31)-1 */ |
|
736 #define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL) |
|
737 #define PNG_UINT_32_MAX ((png_uint_32)(-1)) |
|
738 #define PNG_SIZE_MAX ((png_size_t)(-1)) |
|
739 |
|
740 /* These are constants for fixed point values encoded in the |
|
741 * PNG specification manner (x100000) |
|
742 */ |
|
743 #define PNG_FP_1 100000 |
|
744 #define PNG_FP_HALF 50000 |
|
745 #define PNG_FP_MAX ((png_fixed_point)0x7fffffffL) |
|
746 #define PNG_FP_MIN (-PNG_FP_MAX) |
|
747 |
|
748 /* These describe the color_type field in png_info. */ |
|
749 /* color type masks */ |
|
750 #define PNG_COLOR_MASK_PALETTE 1 |
|
751 #define PNG_COLOR_MASK_COLOR 2 |
|
752 #define PNG_COLOR_MASK_ALPHA 4 |
|
753 |
|
754 /* color types. Note that not all combinations are legal */ |
|
755 #define PNG_COLOR_TYPE_GRAY 0 |
|
756 #define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE) |
|
757 #define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR) |
|
758 #define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA) |
|
759 #define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA) |
|
760 /* aliases */ |
|
761 #define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA |
|
762 #define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA |
|
763 |
|
764 /* This is for compression type. PNG 1.0-1.2 only define the single type. */ |
|
765 #define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */ |
|
766 #define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE |
|
767 |
|
768 /* This is for filter type. PNG 1.0-1.2 only define the single type. */ |
|
769 #define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */ |
|
770 #define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */ |
|
771 #define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE |
|
772 |
|
773 /* These are for the interlacing type. These values should NOT be changed. */ |
|
774 #define PNG_INTERLACE_NONE 0 /* Non-interlaced image */ |
|
775 #define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */ |
|
776 #define PNG_INTERLACE_LAST 2 /* Not a valid value */ |
|
777 |
|
778 /* These are for the oFFs chunk. These values should NOT be changed. */ |
|
779 #define PNG_OFFSET_PIXEL 0 /* Offset in pixels */ |
|
780 #define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */ |
|
781 #define PNG_OFFSET_LAST 2 /* Not a valid value */ |
|
782 |
|
783 /* These are for the pCAL chunk. These values should NOT be changed. */ |
|
784 #define PNG_EQUATION_LINEAR 0 /* Linear transformation */ |
|
785 #define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */ |
|
786 #define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */ |
|
787 #define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */ |
|
788 #define PNG_EQUATION_LAST 4 /* Not a valid value */ |
|
789 |
|
790 /* These are for the sCAL chunk. These values should NOT be changed. */ |
|
791 #define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */ |
|
792 #define PNG_SCALE_METER 1 /* meters per pixel */ |
|
793 #define PNG_SCALE_RADIAN 2 /* radians per pixel */ |
|
794 #define PNG_SCALE_LAST 3 /* Not a valid value */ |
|
795 |
|
796 /* These are for the pHYs chunk. These values should NOT be changed. */ |
|
797 #define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */ |
|
798 #define PNG_RESOLUTION_METER 1 /* pixels/meter */ |
|
799 #define PNG_RESOLUTION_LAST 2 /* Not a valid value */ |
|
800 |
|
801 /* These are for the sRGB chunk. These values should NOT be changed. */ |
|
802 #define PNG_sRGB_INTENT_PERCEPTUAL 0 |
|
803 #define PNG_sRGB_INTENT_RELATIVE 1 |
|
804 #define PNG_sRGB_INTENT_SATURATION 2 |
|
805 #define PNG_sRGB_INTENT_ABSOLUTE 3 |
|
806 #define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */ |
|
807 |
|
808 /* This is for text chunks */ |
|
809 #define PNG_KEYWORD_MAX_LENGTH 79 |
|
810 |
|
811 /* Maximum number of entries in PLTE/sPLT/tRNS arrays */ |
|
812 #define PNG_MAX_PALETTE_LENGTH 256 |
|
813 |
|
814 /* These determine if an ancillary chunk's data has been successfully read |
|
815 * from the PNG header, or if the application has filled in the corresponding |
|
816 * data in the info_struct to be written into the output file. The values |
|
817 * of the PNG_INFO_<chunk> defines should NOT be changed. |
|
818 */ |
|
819 #define PNG_INFO_gAMA 0x0001 |
|
820 #define PNG_INFO_sBIT 0x0002 |
|
821 #define PNG_INFO_cHRM 0x0004 |
|
822 #define PNG_INFO_PLTE 0x0008 |
|
823 #define PNG_INFO_tRNS 0x0010 |
|
824 #define PNG_INFO_bKGD 0x0020 |
|
825 #define PNG_INFO_hIST 0x0040 |
|
826 #define PNG_INFO_pHYs 0x0080 |
|
827 #define PNG_INFO_oFFs 0x0100 |
|
828 #define PNG_INFO_tIME 0x0200 |
|
829 #define PNG_INFO_pCAL 0x0400 |
|
830 #define PNG_INFO_sRGB 0x0800 /* GR-P, 0.96a */ |
|
831 #define PNG_INFO_iCCP 0x1000 /* ESR, 1.0.6 */ |
|
832 #define PNG_INFO_sPLT 0x2000 /* ESR, 1.0.6 */ |
|
833 #define PNG_INFO_sCAL 0x4000 /* ESR, 1.0.6 */ |
|
834 #define PNG_INFO_IDAT 0x8000 /* ESR, 1.0.6 */ |
|
835 |
|
836 /* This is used for the transformation routines, as some of them |
|
837 * change these values for the row. It also should enable using |
|
838 * the routines for other purposes. |
|
839 */ |
|
840 typedef struct png_row_info_struct |
|
841 { |
|
842 png_uint_32 width; /* width of row */ |
|
843 png_size_t rowbytes; /* number of bytes in row */ |
|
844 png_byte color_type; /* color type of row */ |
|
845 png_byte bit_depth; /* bit depth of row */ |
|
846 png_byte channels; /* number of channels (1, 2, 3, or 4) */ |
|
847 png_byte pixel_depth; /* bits per pixel (depth * channels) */ |
|
848 } png_row_info; |
|
849 |
|
850 typedef png_row_info FAR * png_row_infop; |
|
851 typedef png_row_info FAR * FAR * png_row_infopp; |
|
852 |
|
853 /* The complete definition of png_struct has, as of libpng-1.5.0, |
|
854 * been moved into a separate header file that is not accessible to |
|
855 * applications. Read libpng-manual.txt or libpng.3 for more info. |
|
856 */ |
|
857 typedef struct png_struct_def png_struct; |
|
858 typedef PNG_CONST png_struct FAR * png_const_structp; |
|
859 typedef png_struct FAR * png_structp; |
|
860 |
|
861 /* These are the function types for the I/O functions and for the functions |
|
862 * that allow the user to override the default I/O functions with his or her |
|
863 * own. The png_error_ptr type should match that of user-supplied warning |
|
864 * and error functions, while the png_rw_ptr type should match that of the |
|
865 * user read/write data functions. Note that the 'write' function must not |
|
866 * modify the buffer it is passed. The 'read' function, on the other hand, is |
|
867 * expected to return the read data in the buffer. |
|
868 */ |
|
869 typedef PNG_CALLBACK(void, *png_error_ptr, (png_structp, png_const_charp)); |
|
870 typedef PNG_CALLBACK(void, *png_rw_ptr, (png_structp, png_bytep, png_size_t)); |
|
871 typedef PNG_CALLBACK(void, *png_flush_ptr, (png_structp)); |
|
872 typedef PNG_CALLBACK(void, *png_read_status_ptr, (png_structp, png_uint_32, |
|
873 int)); |
|
874 typedef PNG_CALLBACK(void, *png_write_status_ptr, (png_structp, png_uint_32, |
|
875 int)); |
|
876 |
|
877 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED |
|
878 typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_infop)); |
|
879 typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop)); |
|
880 |
|
881 /* The following callback receives png_uint_32 row_number, int pass for the |
|
882 * png_bytep data of the row. When transforming an interlaced image the |
|
883 * row number is the row number within the sub-image of the interlace pass, so |
|
884 * the value will increase to the height of the sub-image (not the full image) |
|
885 * then reset to 0 for the next pass. |
|
886 * |
|
887 * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to |
|
888 * find the output pixel (x,y) given an interlaced sub-image pixel |
|
889 * (row,col,pass). (See below for these macros.) |
|
890 */ |
|
891 typedef PNG_CALLBACK(void, *png_progressive_row_ptr, (png_structp, png_bytep, |
|
892 png_uint_32, int)); |
|
893 #endif |
|
894 |
|
895 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ |
|
896 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) |
|
897 typedef PNG_CALLBACK(void, *png_user_transform_ptr, (png_structp, png_row_infop, |
|
898 png_bytep)); |
|
899 #endif |
|
900 |
|
901 #ifdef PNG_USER_CHUNKS_SUPPORTED |
|
902 typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp, |
|
903 png_unknown_chunkp)); |
|
904 #endif |
|
905 #ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED |
|
906 typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (png_structp)); |
|
907 #endif |
|
908 |
|
909 #ifdef PNG_SETJMP_SUPPORTED |
|
910 /* This must match the function definition in <setjmp.h>, and the application |
|
911 * must include this before png.h to obtain the definition of jmp_buf. The |
|
912 * function is required to be PNG_NORETURN, but this is not checked. If the |
|
913 * function does return the application will crash via an abort() or similar |
|
914 * system level call. |
|
915 * |
|
916 * If you get a warning here while building the library you may need to make |
|
917 * changes to ensure that pnglibconf.h records the calling convention used by |
|
918 * your compiler. This may be very difficult - try using a different compiler |
|
919 * to build the library! |
|
920 */ |
|
921 PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)), typedef); |
|
922 #endif |
|
923 |
|
924 /* Transform masks for the high-level interface */ |
|
925 #define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */ |
|
926 #define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */ |
|
927 #define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */ |
|
928 #define PNG_TRANSFORM_PACKING 0x0004 /* read and write */ |
|
929 #define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */ |
|
930 #define PNG_TRANSFORM_EXPAND 0x0010 /* read only */ |
|
931 #define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */ |
|
932 #define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */ |
|
933 #define PNG_TRANSFORM_BGR 0x0080 /* read and write */ |
|
934 #define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */ |
|
935 #define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */ |
|
936 #define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */ |
|
937 #define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* write only */ |
|
938 /* Added to libpng-1.2.34 */ |
|
939 #define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER |
|
940 #define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */ |
|
941 /* Added to libpng-1.4.0 */ |
|
942 #define PNG_TRANSFORM_GRAY_TO_RGB 0x2000 /* read only */ |
|
943 /* Added to libpng-1.5.4 */ |
|
944 #define PNG_TRANSFORM_EXPAND_16 0x4000 /* read only */ |
|
945 #define PNG_TRANSFORM_SCALE_16 0x8000 /* read only */ |
|
946 |
|
947 /* Flags for MNG supported features */ |
|
948 #define PNG_FLAG_MNG_EMPTY_PLTE 0x01 |
|
949 #define PNG_FLAG_MNG_FILTER_64 0x04 |
|
950 #define PNG_ALL_MNG_FEATURES 0x05 |
|
951 |
|
952 /* NOTE: prior to 1.5 these functions had no 'API' style declaration, |
|
953 * this allowed the zlib default functions to be used on Windows |
|
954 * platforms. In 1.5 the zlib default malloc (which just calls malloc and |
|
955 * ignores the first argument) should be completely compatible with the |
|
956 * following. |
|
957 */ |
|
958 typedef PNG_CALLBACK(png_voidp, *png_malloc_ptr, (png_structp, |
|
959 png_alloc_size_t)); |
|
960 typedef PNG_CALLBACK(void, *png_free_ptr, (png_structp, png_voidp)); |
|
961 |
|
962 typedef png_struct FAR * FAR * png_structpp; |
|
963 |
|
964 /* Section 3: exported functions |
|
965 * Here are the function definitions most commonly used. This is not |
|
966 * the place to find out how to use libpng. See libpng-manual.txt for the |
|
967 * full explanation, see example.c for the summary. This just provides |
|
968 * a simple one line description of the use of each function. |
|
969 * |
|
970 * The PNG_EXPORT() and PNG_EXPORTA() macros used below are defined in |
|
971 * pngconf.h and in the *.dfn files in the scripts directory. |
|
972 * |
|
973 * PNG_EXPORT(ordinal, type, name, (args)); |
|
974 * |
|
975 * ordinal: ordinal that is used while building |
|
976 * *.def files. The ordinal value is only |
|
977 * relevant when preprocessing png.h with |
|
978 * the *.dfn files for building symbol table |
|
979 * entries, and are removed by pngconf.h. |
|
980 * type: return type of the function |
|
981 * name: function name |
|
982 * args: function arguments, with types |
|
983 * |
|
984 * When we wish to append attributes to a function prototype we use |
|
985 * the PNG_EXPORTA() macro instead. |
|
986 * |
|
987 * PNG_EXPORTA(ordinal, type, name, (args), attributes); |
|
988 * |
|
989 * ordinal, type, name, and args: same as in PNG_EXPORT(). |
|
990 * attributes: function attributes |
|
991 */ |
|
992 |
|
993 /* Returns the version number of the library */ |
|
994 PNG_EXPORT(1, png_uint_32, png_access_version_number, (void)); |
|
995 |
|
996 /* Tell lib we have already handled the first <num_bytes> magic bytes. |
|
997 * Handling more than 8 bytes from the beginning of the file is an error. |
|
998 */ |
|
999 PNG_EXPORT(2, void, png_set_sig_bytes, (png_structp png_ptr, int num_bytes)); |
|
1000 |
|
1001 /* Check sig[start] through sig[start + num_to_check - 1] to see if it's a |
|
1002 * PNG file. Returns zero if the supplied bytes match the 8-byte PNG |
|
1003 * signature, and non-zero otherwise. Having num_to_check == 0 or |
|
1004 * start > 7 will always fail (ie return non-zero). |
|
1005 */ |
|
1006 PNG_EXPORT(3, int, png_sig_cmp, (png_const_bytep sig, png_size_t start, |
|
1007 png_size_t num_to_check)); |
|
1008 |
|
1009 /* Simple signature checking function. This is the same as calling |
|
1010 * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n). |
|
1011 */ |
|
1012 #define png_check_sig(sig, n) !png_sig_cmp((sig), 0, (n)) |
|
1013 |
|
1014 /* Allocate and initialize png_ptr struct for reading, and any other memory. */ |
|
1015 PNG_EXPORTA(4, png_structp, png_create_read_struct, |
|
1016 (png_const_charp user_png_ver, png_voidp error_ptr, |
|
1017 png_error_ptr error_fn, png_error_ptr warn_fn), |
|
1018 PNG_ALLOCATED); |
|
1019 |
|
1020 /* Allocate and initialize png_ptr struct for writing, and any other memory */ |
|
1021 PNG_EXPORTA(5, png_structp, png_create_write_struct, |
|
1022 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, |
|
1023 png_error_ptr warn_fn), |
|
1024 PNG_ALLOCATED); |
|
1025 |
|
1026 PNG_EXPORT(6, png_size_t, png_get_compression_buffer_size, |
|
1027 (png_const_structp png_ptr)); |
|
1028 |
|
1029 PNG_EXPORT(7, void, png_set_compression_buffer_size, (png_structp png_ptr, |
|
1030 png_size_t size)); |
|
1031 |
|
1032 /* Moved from pngconf.h in 1.4.0 and modified to ensure setjmp/longjmp |
|
1033 * match up. |
|
1034 */ |
|
1035 #ifdef PNG_SETJMP_SUPPORTED |
|
1036 /* This function returns the jmp_buf built in to *png_ptr. It must be |
|
1037 * supplied with an appropriate 'longjmp' function to use on that jmp_buf |
|
1038 * unless the default error function is overridden in which case NULL is |
|
1039 * acceptable. The size of the jmp_buf is checked against the actual size |
|
1040 * allocated by the library - the call will return NULL on a mismatch |
|
1041 * indicating an ABI mismatch. |
|
1042 */ |
|
1043 PNG_EXPORT(8, jmp_buf*, png_set_longjmp_fn, (png_structp png_ptr, |
|
1044 png_longjmp_ptr longjmp_fn, size_t jmp_buf_size)); |
|
1045 # define png_jmpbuf(png_ptr) \ |
|
1046 (*png_set_longjmp_fn((png_ptr), longjmp, sizeof (jmp_buf))) |
|
1047 #else |
|
1048 # define png_jmpbuf(png_ptr) \ |
|
1049 (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP) |
|
1050 #endif |
|
1051 /* This function should be used by libpng applications in place of |
|
1052 * longjmp(png_ptr->jmpbuf, val). If longjmp_fn() has been set, it |
|
1053 * will use it; otherwise it will call PNG_ABORT(). This function was |
|
1054 * added in libpng-1.5.0. |
|
1055 */ |
|
1056 PNG_EXPORTA(9, void, png_longjmp, (png_structp png_ptr, int val), |
|
1057 PNG_NORETURN); |
|
1058 |
|
1059 #ifdef PNG_READ_SUPPORTED |
|
1060 /* Reset the compression stream */ |
|
1061 PNG_EXPORT(10, int, png_reset_zstream, (png_structp png_ptr)); |
|
1062 #endif |
|
1063 |
|
1064 /* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */ |
|
1065 #ifdef PNG_USER_MEM_SUPPORTED |
|
1066 PNG_EXPORTA(11, png_structp, png_create_read_struct_2, |
|
1067 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, |
|
1068 png_error_ptr warn_fn, |
|
1069 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), |
|
1070 PNG_ALLOCATED); |
|
1071 PNG_EXPORTA(12, png_structp, png_create_write_struct_2, |
|
1072 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, |
|
1073 png_error_ptr warn_fn, |
|
1074 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), |
|
1075 PNG_ALLOCATED); |
|
1076 #endif |
|
1077 |
|
1078 /* Write the PNG file signature. */ |
|
1079 PNG_EXPORT(13, void, png_write_sig, (png_structp png_ptr)); |
|
1080 |
|
1081 /* Write a PNG chunk - size, type, (optional) data, CRC. */ |
|
1082 PNG_EXPORT(14, void, png_write_chunk, (png_structp png_ptr, png_const_bytep |
|
1083 chunk_name, png_const_bytep data, png_size_t length)); |
|
1084 |
|
1085 /* Write the start of a PNG chunk - length and chunk name. */ |
|
1086 PNG_EXPORT(15, void, png_write_chunk_start, (png_structp png_ptr, |
|
1087 png_const_bytep chunk_name, png_uint_32 length)); |
|
1088 |
|
1089 /* Write the data of a PNG chunk started with png_write_chunk_start(). */ |
|
1090 PNG_EXPORT(16, void, png_write_chunk_data, (png_structp png_ptr, |
|
1091 png_const_bytep data, png_size_t length)); |
|
1092 |
|
1093 /* Finish a chunk started with png_write_chunk_start() (includes CRC). */ |
|
1094 PNG_EXPORT(17, void, png_write_chunk_end, (png_structp png_ptr)); |
|
1095 |
|
1096 /* Allocate and initialize the info structure */ |
|
1097 PNG_EXPORTA(18, png_infop, png_create_info_struct, (png_structp png_ptr), |
|
1098 PNG_ALLOCATED); |
|
1099 |
|
1100 PNG_EXPORT(19, void, png_info_init_3, (png_infopp info_ptr, |
|
1101 png_size_t png_info_struct_size)); |
|
1102 |
|
1103 /* Writes all the PNG information before the image. */ |
|
1104 PNG_EXPORT(20, void, png_write_info_before_PLTE, |
|
1105 (png_structp png_ptr, png_infop info_ptr)); |
|
1106 PNG_EXPORT(21, void, png_write_info, |
|
1107 (png_structp png_ptr, png_infop info_ptr)); |
|
1108 |
|
1109 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
|
1110 /* Read the information before the actual image data. */ |
|
1111 PNG_EXPORT(22, void, png_read_info, |
|
1112 (png_structp png_ptr, png_infop info_ptr)); |
|
1113 #endif |
|
1114 |
|
1115 #ifdef PNG_TIME_RFC1123_SUPPORTED |
|
1116 PNG_EXPORT(23, png_const_charp, png_convert_to_rfc1123, |
|
1117 (png_structp png_ptr, |
|
1118 png_const_timep ptime)); |
|
1119 #endif |
|
1120 |
|
1121 #ifdef PNG_CONVERT_tIME_SUPPORTED |
|
1122 /* Convert from a struct tm to png_time */ |
|
1123 PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime, |
|
1124 PNG_CONST struct tm FAR * ttime)); |
|
1125 |
|
1126 /* Convert from time_t to png_time. Uses gmtime() */ |
|
1127 PNG_EXPORT(25, void, png_convert_from_time_t, |
|
1128 (png_timep ptime, time_t ttime)); |
|
1129 #endif /* PNG_CONVERT_tIME_SUPPORTED */ |
|
1130 |
|
1131 #ifdef PNG_READ_EXPAND_SUPPORTED |
|
1132 /* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */ |
|
1133 PNG_EXPORT(26, void, png_set_expand, (png_structp png_ptr)); |
|
1134 PNG_EXPORT(27, void, png_set_expand_gray_1_2_4_to_8, (png_structp png_ptr)); |
|
1135 PNG_EXPORT(28, void, png_set_palette_to_rgb, (png_structp png_ptr)); |
|
1136 PNG_EXPORT(29, void, png_set_tRNS_to_alpha, (png_structp png_ptr)); |
|
1137 #endif |
|
1138 |
|
1139 #ifdef PNG_READ_EXPAND_16_SUPPORTED |
|
1140 /* Expand to 16-bit channels, forces conversion of palette to RGB and expansion |
|
1141 * of a tRNS chunk if present. |
|
1142 */ |
|
1143 PNG_EXPORT(221, void, png_set_expand_16, (png_structp png_ptr)); |
|
1144 #endif |
|
1145 |
|
1146 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) |
|
1147 /* Use blue, green, red order for pixels. */ |
|
1148 PNG_EXPORT(30, void, png_set_bgr, (png_structp png_ptr)); |
|
1149 #endif |
|
1150 |
|
1151 #ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED |
|
1152 /* Expand the grayscale to 24-bit RGB if necessary. */ |
|
1153 PNG_EXPORT(31, void, png_set_gray_to_rgb, (png_structp png_ptr)); |
|
1154 #endif |
|
1155 |
|
1156 #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED |
|
1157 /* Reduce RGB to grayscale. */ |
|
1158 #define PNG_ERROR_ACTION_NONE 1 |
|
1159 #define PNG_ERROR_ACTION_WARN 2 |
|
1160 #define PNG_ERROR_ACTION_ERROR 3 |
|
1161 #define PNG_RGB_TO_GRAY_DEFAULT (-1)/*for red/green coefficients*/ |
|
1162 |
|
1163 PNG_FP_EXPORT(32, void, png_set_rgb_to_gray, (png_structp png_ptr, |
|
1164 int error_action, double red, double green)) |
|
1165 PNG_FIXED_EXPORT(33, void, png_set_rgb_to_gray_fixed, (png_structp png_ptr, |
|
1166 int error_action, png_fixed_point red, png_fixed_point green)) |
|
1167 |
|
1168 PNG_EXPORT(34, png_byte, png_get_rgb_to_gray_status, (png_const_structp |
|
1169 png_ptr)); |
|
1170 #endif |
|
1171 |
|
1172 #ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED |
|
1173 PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth, |
|
1174 png_colorp palette)); |
|
1175 #endif |
|
1176 |
|
1177 #ifdef PNG_READ_ALPHA_MODE_SUPPORTED |
|
1178 /* How the alpha channel is interpreted - this affects how the color channels of |
|
1179 * a PNG file are returned when an alpha channel, or tRNS chunk in a palette |
|
1180 * file, is present. |
|
1181 * |
|
1182 * This has no effect on the way pixels are written into a PNG output |
|
1183 * datastream. The color samples in a PNG datastream are never premultiplied |
|
1184 * with the alpha samples. |
|
1185 * |
|
1186 * The default is to return data according to the PNG specification: the alpha |
|
1187 * channel is a linear measure of the contribution of the pixel to the |
|
1188 * corresponding composited pixel. The gamma encoded color channels must be |
|
1189 * scaled according to the contribution and to do this it is necessary to undo |
|
1190 * the encoding, scale the color values, perform the composition and reencode |
|
1191 * the values. This is the 'PNG' mode. |
|
1192 * |
|
1193 * The alternative is to 'associate' the alpha with the color information by |
|
1194 * storing color channel values that have been scaled by the alpha. The |
|
1195 * advantage is that the color channels can be resampled (the image can be |
|
1196 * scaled) in this form. The disadvantage is that normal practice is to store |
|
1197 * linear, not (gamma) encoded, values and this requires 16-bit channels for |
|
1198 * still images rather than the 8-bit channels that are just about sufficient if |
|
1199 * gamma encoding is used. In addition all non-transparent pixel values, |
|
1200 * including completely opaque ones, must be gamma encoded to produce the final |
|
1201 * image. This is the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' mode (the |
|
1202 * latter being the two common names for associated alpha color channels.) |
|
1203 * |
|
1204 * Since it is not necessary to perform arithmetic on opaque color values so |
|
1205 * long as they are not to be resampled and are in the final color space it is |
|
1206 * possible to optimize the handling of alpha by storing the opaque pixels in |
|
1207 * the PNG format (adjusted for the output color space) while storing partially |
|
1208 * opaque pixels in the standard, linear, format. The accuracy required for |
|
1209 * standard alpha composition is relatively low, because the pixels are |
|
1210 * isolated, therefore typically the accuracy loss in storing 8-bit linear |
|
1211 * values is acceptable. (This is not true if the alpha channel is used to |
|
1212 * simulate transparency over large areas - use 16 bits or the PNG mode in |
|
1213 * this case!) This is the 'OPTIMIZED' mode. For this mode a pixel is |
|
1214 * treated as opaque only if the alpha value is equal to the maximum value. |
|
1215 * |
|
1216 * The final choice is to gamma encode the alpha channel as well. This is |
|
1217 * broken because, in practice, no implementation that uses this choice |
|
1218 * correctly undoes the encoding before handling alpha composition. Use this |
|
1219 * choice only if other serious errors in the software or hardware you use |
|
1220 * mandate it; the typical serious error is for dark halos to appear around |
|
1221 * opaque areas of the composited PNG image because of arithmetic overflow. |
|
1222 * |
|
1223 * The API function png_set_alpha_mode specifies which of these choices to use |
|
1224 * with an enumerated 'mode' value and the gamma of the required output: |
|
1225 */ |
|
1226 #define PNG_ALPHA_PNG 0 /* according to the PNG standard */ |
|
1227 #define PNG_ALPHA_STANDARD 1 /* according to Porter/Duff */ |
|
1228 #define PNG_ALPHA_ASSOCIATED 1 /* as above; this is the normal practice */ |
|
1229 #define PNG_ALPHA_PREMULTIPLIED 1 /* as above */ |
|
1230 #define PNG_ALPHA_OPTIMIZED 2 /* 'PNG' for opaque pixels, else 'STANDARD' */ |
|
1231 #define PNG_ALPHA_BROKEN 3 /* the alpha channel is gamma encoded */ |
|
1232 |
|
1233 PNG_FP_EXPORT(227, void, png_set_alpha_mode, (png_structp png_ptr, int mode, |
|
1234 double output_gamma)) |
|
1235 PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structp png_ptr, |
|
1236 int mode, png_fixed_point output_gamma)) |
|
1237 #endif |
|
1238 |
|
1239 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED) |
|
1240 /* The output_gamma value is a screen gamma in libpng terminology: it expresses |
|
1241 * how to decode the output values, not how they are encoded. The values used |
|
1242 * correspond to the normal numbers used to describe the overall gamma of a |
|
1243 * computer display system; for example 2.2 for an sRGB conformant system. The |
|
1244 * values are scaled by 100000 in the _fixed version of the API (so 220000 for |
|
1245 * sRGB.) |
|
1246 * |
|
1247 * The inverse of the value is always used to provide a default for the PNG file |
|
1248 * encoding if it has no gAMA chunk and if png_set_gamma() has not been called |
|
1249 * to override the PNG gamma information. |
|
1250 * |
|
1251 * When the ALPHA_OPTIMIZED mode is selected the output gamma is used to encode |
|
1252 * opaque pixels however pixels with lower alpha values are not encoded, |
|
1253 * regardless of the output gamma setting. |
|
1254 * |
|
1255 * When the standard Porter Duff handling is requested with mode 1 the output |
|
1256 * encoding is set to be linear and the output_gamma value is only relevant |
|
1257 * as a default for input data that has no gamma information. The linear output |
|
1258 * encoding will be overridden if png_set_gamma() is called - the results may be |
|
1259 * highly unexpected! |
|
1260 * |
|
1261 * The following numbers are derived from the sRGB standard and the research |
|
1262 * behind it. sRGB is defined to be approximated by a PNG gAMA chunk value of |
|
1263 * 0.45455 (1/2.2) for PNG. The value implicitly includes any viewing |
|
1264 * correction required to take account of any differences in the color |
|
1265 * environment of the original scene and the intended display environment; the |
|
1266 * value expresses how to *decode* the image for display, not how the original |
|
1267 * data was *encoded*. |
|
1268 * |
|
1269 * sRGB provides a peg for the PNG standard by defining a viewing environment. |
|
1270 * sRGB itself, and earlier TV standards, actually use a more complex transform |
|
1271 * (a linear portion then a gamma 2.4 power law) than PNG can express. (PNG is |
|
1272 * limited to simple power laws.) By saying that an image for direct display on |
|
1273 * an sRGB conformant system should be stored with a gAMA chunk value of 45455 |
|
1274 * (11.3.3.2 and 11.3.3.5 of the ISO PNG specification) the PNG specification |
|
1275 * makes it possible to derive values for other display systems and |
|
1276 * environments. |
|
1277 * |
|
1278 * The Mac value is deduced from the sRGB based on an assumption that the actual |
|
1279 * extra viewing correction used in early Mac display systems was implemented as |
|
1280 * a power 1.45 lookup table. |
|
1281 * |
|
1282 * Any system where a programmable lookup table is used or where the behavior of |
|
1283 * the final display device characteristics can be changed requires system |
|
1284 * specific code to obtain the current characteristic. However this can be |
|
1285 * difficult and most PNG gamma correction only requires an approximate value. |
|
1286 * |
|
1287 * By default, if png_set_alpha_mode() is not called, libpng assumes that all |
|
1288 * values are unencoded, linear, values and that the output device also has a |
|
1289 * linear characteristic. This is only very rarely correct - it is invariably |
|
1290 * better to call png_set_alpha_mode() with PNG_DEFAULT_sRGB than rely on the |
|
1291 * default if you don't know what the right answer is! |
|
1292 * |
|
1293 * The special value PNG_GAMMA_MAC_18 indicates an older Mac system (pre Mac OS |
|
1294 * 10.6) which used a correction table to implement a somewhat lower gamma on an |
|
1295 * otherwise sRGB system. |
|
1296 * |
|
1297 * Both these values are reserved (not simple gamma values) in order to allow |
|
1298 * more precise correction internally in the future. |
|
1299 * |
|
1300 * NOTE: the following values can be passed to either the fixed or floating |
|
1301 * point APIs, but the floating point API will also accept floating point |
|
1302 * values. |
|
1303 */ |
|
1304 #define PNG_DEFAULT_sRGB -1 /* sRGB gamma and color space */ |
|
1305 #define PNG_GAMMA_MAC_18 -2 /* Old Mac '1.8' gamma and color space */ |
|
1306 #define PNG_GAMMA_sRGB 220000 /* Television standards--matches sRGB gamma */ |
|
1307 #define PNG_GAMMA_LINEAR PNG_FP_1 /* Linear */ |
|
1308 #endif |
|
1309 |
|
1310 /* The following are examples of calls to png_set_alpha_mode to achieve the |
|
1311 * required overall gamma correction and, where necessary, alpha |
|
1312 * premultiplication. |
|
1313 * |
|
1314 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); |
|
1315 * This is the default libpng handling of the alpha channel - it is not |
|
1316 * pre-multiplied into the color components. In addition the call states |
|
1317 * that the output is for a sRGB system and causes all PNG files without gAMA |
|
1318 * chunks to be assumed to be encoded using sRGB. |
|
1319 * |
|
1320 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); |
|
1321 * In this case the output is assumed to be something like an sRGB conformant |
|
1322 * display preceeded by a power-law lookup table of power 1.45. This is how |
|
1323 * early Mac systems behaved. |
|
1324 * |
|
1325 * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_GAMMA_LINEAR); |
|
1326 * This is the classic Jim Blinn approach and will work in academic |
|
1327 * environments where everything is done by the book. It has the shortcoming |
|
1328 * of assuming that input PNG data with no gamma information is linear - this |
|
1329 * is unlikely to be correct unless the PNG files where generated locally. |
|
1330 * Most of the time the output precision will be so low as to show |
|
1331 * significant banding in dark areas of the image. |
|
1332 * |
|
1333 * png_set_expand_16(pp); |
|
1334 * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_DEFAULT_sRGB); |
|
1335 * This is a somewhat more realistic Jim Blinn inspired approach. PNG files |
|
1336 * are assumed to have the sRGB encoding if not marked with a gamma value and |
|
1337 * the output is always 16 bits per component. This permits accurate scaling |
|
1338 * and processing of the data. If you know that your input PNG files were |
|
1339 * generated locally you might need to replace PNG_DEFAULT_sRGB with the |
|
1340 * correct value for your system. |
|
1341 * |
|
1342 * png_set_alpha_mode(pp, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB); |
|
1343 * If you just need to composite the PNG image onto an existing background |
|
1344 * and if you control the code that does this you can use the optimization |
|
1345 * setting. In this case you just copy completely opaque pixels to the |
|
1346 * output. For pixels that are not completely transparent (you just skip |
|
1347 * those) you do the composition math using png_composite or png_composite_16 |
|
1348 * below then encode the resultant 8-bit or 16-bit values to match the output |
|
1349 * encoding. |
|
1350 * |
|
1351 * Other cases |
|
1352 * If neither the PNG nor the standard linear encoding work for you because |
|
1353 * of the software or hardware you use then you have a big problem. The PNG |
|
1354 * case will probably result in halos around the image. The linear encoding |
|
1355 * will probably result in a washed out, too bright, image (it's actually too |
|
1356 * contrasty.) Try the ALPHA_OPTIMIZED mode above - this will probably |
|
1357 * substantially reduce the halos. Alternatively try: |
|
1358 * |
|
1359 * png_set_alpha_mode(pp, PNG_ALPHA_BROKEN, PNG_DEFAULT_sRGB); |
|
1360 * This option will also reduce the halos, but there will be slight dark |
|
1361 * halos round the opaque parts of the image where the background is light. |
|
1362 * In the OPTIMIZED mode the halos will be light halos where the background |
|
1363 * is dark. Take your pick - the halos are unavoidable unless you can get |
|
1364 * your hardware/software fixed! (The OPTIMIZED approach is slightly |
|
1365 * faster.) |
|
1366 * |
|
1367 * When the default gamma of PNG files doesn't match the output gamma. |
|
1368 * If you have PNG files with no gamma information png_set_alpha_mode allows |
|
1369 * you to provide a default gamma, but it also sets the ouput gamma to the |
|
1370 * matching value. If you know your PNG files have a gamma that doesn't |
|
1371 * match the output you can take advantage of the fact that |
|
1372 * png_set_alpha_mode always sets the output gamma but only sets the PNG |
|
1373 * default if it is not already set: |
|
1374 * |
|
1375 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); |
|
1376 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); |
|
1377 * The first call sets both the default and the output gamma values, the |
|
1378 * second call overrides the output gamma without changing the default. This |
|
1379 * is easier than achieving the same effect with png_set_gamma. You must use |
|
1380 * PNG_ALPHA_PNG for the first call - internal checking in png_set_alpha will |
|
1381 * fire if more than one call to png_set_alpha_mode and png_set_background is |
|
1382 * made in the same read operation, however multiple calls with PNG_ALPHA_PNG |
|
1383 * are ignored. |
|
1384 */ |
|
1385 |
|
1386 #ifdef PNG_READ_STRIP_ALPHA_SUPPORTED |
|
1387 PNG_EXPORT(36, void, png_set_strip_alpha, (png_structp png_ptr)); |
|
1388 #endif |
|
1389 |
|
1390 #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \ |
|
1391 defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED) |
|
1392 PNG_EXPORT(37, void, png_set_swap_alpha, (png_structp png_ptr)); |
|
1393 #endif |
|
1394 |
|
1395 #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \ |
|
1396 defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED) |
|
1397 PNG_EXPORT(38, void, png_set_invert_alpha, (png_structp png_ptr)); |
|
1398 #endif |
|
1399 |
|
1400 #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED) |
|
1401 /* Add a filler byte to 8-bit Gray or 24-bit RGB images. */ |
|
1402 PNG_EXPORT(39, void, png_set_filler, (png_structp png_ptr, png_uint_32 filler, |
|
1403 int flags)); |
|
1404 /* The values of the PNG_FILLER_ defines should NOT be changed */ |
|
1405 # define PNG_FILLER_BEFORE 0 |
|
1406 # define PNG_FILLER_AFTER 1 |
|
1407 /* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */ |
|
1408 PNG_EXPORT(40, void, png_set_add_alpha, |
|
1409 (png_structp png_ptr, png_uint_32 filler, |
|
1410 int flags)); |
|
1411 #endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */ |
|
1412 |
|
1413 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) |
|
1414 /* Swap bytes in 16-bit depth files. */ |
|
1415 PNG_EXPORT(41, void, png_set_swap, (png_structp png_ptr)); |
|
1416 #endif |
|
1417 |
|
1418 #if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED) |
|
1419 /* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */ |
|
1420 PNG_EXPORT(42, void, png_set_packing, (png_structp png_ptr)); |
|
1421 #endif |
|
1422 |
|
1423 #if defined(PNG_READ_PACKSWAP_SUPPORTED) || \ |
|
1424 defined(PNG_WRITE_PACKSWAP_SUPPORTED) |
|
1425 /* Swap packing order of pixels in bytes. */ |
|
1426 PNG_EXPORT(43, void, png_set_packswap, (png_structp png_ptr)); |
|
1427 #endif |
|
1428 |
|
1429 #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED) |
|
1430 /* Converts files to legal bit depths. */ |
|
1431 PNG_EXPORT(44, void, png_set_shift, (png_structp png_ptr, png_const_color_8p |
|
1432 true_bits)); |
|
1433 #endif |
|
1434 |
|
1435 #if defined(PNG_READ_INTERLACING_SUPPORTED) || \ |
|
1436 defined(PNG_WRITE_INTERLACING_SUPPORTED) |
|
1437 /* Have the code handle the interlacing. Returns the number of passes. |
|
1438 * MUST be called before png_read_update_info or png_start_read_image, |
|
1439 * otherwise it will not have the desired effect. Note that it is still |
|
1440 * necessary to call png_read_row or png_read_rows png_get_image_height |
|
1441 * times for each pass. |
|
1442 */ |
|
1443 PNG_EXPORT(45, int, png_set_interlace_handling, (png_structp png_ptr)); |
|
1444 #endif |
|
1445 |
|
1446 #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED) |
|
1447 /* Invert monochrome files */ |
|
1448 PNG_EXPORT(46, void, png_set_invert_mono, (png_structp png_ptr)); |
|
1449 #endif |
|
1450 |
|
1451 #ifdef PNG_READ_BACKGROUND_SUPPORTED |
|
1452 /* Handle alpha and tRNS by replacing with a background color. Prior to |
|
1453 * libpng-1.5.4 this API must not be called before the PNG file header has been |
|
1454 * read. Doing so will result in unexpected behavior and possible warnings or |
|
1455 * errors if the PNG file contains a bKGD chunk. |
|
1456 */ |
|
1457 PNG_FP_EXPORT(47, void, png_set_background, (png_structp png_ptr, |
|
1458 png_const_color_16p background_color, int background_gamma_code, |
|
1459 int need_expand, double background_gamma)) |
|
1460 PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structp png_ptr, |
|
1461 png_const_color_16p background_color, int background_gamma_code, |
|
1462 int need_expand, png_fixed_point background_gamma)) |
|
1463 #endif |
|
1464 #ifdef PNG_READ_BACKGROUND_SUPPORTED |
|
1465 # define PNG_BACKGROUND_GAMMA_UNKNOWN 0 |
|
1466 # define PNG_BACKGROUND_GAMMA_SCREEN 1 |
|
1467 # define PNG_BACKGROUND_GAMMA_FILE 2 |
|
1468 # define PNG_BACKGROUND_GAMMA_UNIQUE 3 |
|
1469 #endif |
|
1470 |
|
1471 #ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED |
|
1472 /* Scale a 16-bit depth file down to 8-bit, accurately. */ |
|
1473 PNG_EXPORT(229, void, png_set_scale_16, (png_structp png_ptr)); |
|
1474 #endif |
|
1475 |
|
1476 #ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED |
|
1477 #define PNG_READ_16_TO_8 SUPPORTED /* Name prior to 1.5.4 */ |
|
1478 /* Strip the second byte of information from a 16-bit depth file. */ |
|
1479 PNG_EXPORT(48, void, png_set_strip_16, (png_structp png_ptr)); |
|
1480 #endif |
|
1481 |
|
1482 #ifdef PNG_READ_QUANTIZE_SUPPORTED |
|
1483 /* Turn on quantizing, and reduce the palette to the number of colors |
|
1484 * available. |
|
1485 */ |
|
1486 PNG_EXPORT(49, void, png_set_quantize, |
|
1487 (png_structp png_ptr, png_colorp palette, |
|
1488 int num_palette, int maximum_colors, png_const_uint_16p histogram, |
|
1489 int full_quantize)); |
|
1490 #endif |
|
1491 |
|
1492 #ifdef PNG_READ_GAMMA_SUPPORTED |
|
1493 /* The threshold on gamma processing is configurable but hard-wired into the |
|
1494 * library. The following is the floating point variant. |
|
1495 */ |
|
1496 #define PNG_GAMMA_THRESHOLD (PNG_GAMMA_THRESHOLD_FIXED*.00001) |
|
1497 |
|
1498 /* Handle gamma correction. Screen_gamma=(display_exponent). |
|
1499 * NOTE: this API simply sets the screen and file gamma values. It will |
|
1500 * therefore override the value for gamma in a PNG file if it is called after |
|
1501 * the file header has been read - use with care - call before reading the PNG |
|
1502 * file for best results! |
|
1503 * |
|
1504 * These routines accept the same gamma values as png_set_alpha_mode (described |
|
1505 * above). The PNG_GAMMA_ defines and PNG_DEFAULT_sRGB can be passed to either |
|
1506 * API (floating point or fixed.) Notice, however, that the 'file_gamma' value |
|
1507 * is the inverse of a 'screen gamma' value. |
|
1508 */ |
|
1509 PNG_FP_EXPORT(50, void, png_set_gamma, |
|
1510 (png_structp png_ptr, double screen_gamma, |
|
1511 double override_file_gamma)) |
|
1512 PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structp png_ptr, |
|
1513 png_fixed_point screen_gamma, png_fixed_point override_file_gamma)) |
|
1514 #endif |
|
1515 |
|
1516 #ifdef PNG_WRITE_FLUSH_SUPPORTED |
|
1517 /* Set how many lines between output flushes - 0 for no flushing */ |
|
1518 PNG_EXPORT(51, void, png_set_flush, (png_structp png_ptr, int nrows)); |
|
1519 /* Flush the current PNG output buffer */ |
|
1520 PNG_EXPORT(52, void, png_write_flush, (png_structp png_ptr)); |
|
1521 #endif |
|
1522 |
|
1523 /* Optional update palette with requested transformations */ |
|
1524 PNG_EXPORT(53, void, png_start_read_image, (png_structp png_ptr)); |
|
1525 |
|
1526 /* Optional call to update the users info structure */ |
|
1527 PNG_EXPORT(54, void, png_read_update_info, |
|
1528 (png_structp png_ptr, png_infop info_ptr)); |
|
1529 |
|
1530 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
|
1531 /* Read one or more rows of image data. */ |
|
1532 PNG_EXPORT(55, void, png_read_rows, (png_structp png_ptr, png_bytepp row, |
|
1533 png_bytepp display_row, png_uint_32 num_rows)); |
|
1534 #endif |
|
1535 |
|
1536 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
|
1537 /* Read a row of data. */ |
|
1538 PNG_EXPORT(56, void, png_read_row, (png_structp png_ptr, png_bytep row, |
|
1539 png_bytep display_row)); |
|
1540 #endif |
|
1541 |
|
1542 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
|
1543 /* Read the whole image into memory at once. */ |
|
1544 PNG_EXPORT(57, void, png_read_image, (png_structp png_ptr, png_bytepp image)); |
|
1545 #endif |
|
1546 |
|
1547 /* Write a row of image data */ |
|
1548 PNG_EXPORT(58, void, png_write_row, |
|
1549 (png_structp png_ptr, png_const_bytep row)); |
|
1550 |
|
1551 /* Write a few rows of image data: (*row) is not written; however, the type |
|
1552 * is declared as writeable to maintain compatibility with previous versions |
|
1553 * of libpng and to allow the 'display_row' array from read_rows to be passed |
|
1554 * unchanged to write_rows. |
|
1555 */ |
|
1556 PNG_EXPORT(59, void, png_write_rows, (png_structp png_ptr, png_bytepp row, |
|
1557 png_uint_32 num_rows)); |
|
1558 |
|
1559 /* Write the image data */ |
|
1560 PNG_EXPORT(60, void, png_write_image, |
|
1561 (png_structp png_ptr, png_bytepp image)); |
|
1562 |
|
1563 /* Write the end of the PNG file. */ |
|
1564 PNG_EXPORT(61, void, png_write_end, |
|
1565 (png_structp png_ptr, png_infop info_ptr)); |
|
1566 |
|
1567 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
|
1568 /* Read the end of the PNG file. */ |
|
1569 PNG_EXPORT(62, void, png_read_end, (png_structp png_ptr, png_infop info_ptr)); |
|
1570 #endif |
|
1571 |
|
1572 /* Free any memory associated with the png_info_struct */ |
|
1573 PNG_EXPORT(63, void, png_destroy_info_struct, (png_structp png_ptr, |
|
1574 png_infopp info_ptr_ptr)); |
|
1575 |
|
1576 /* Free any memory associated with the png_struct and the png_info_structs */ |
|
1577 PNG_EXPORT(64, void, png_destroy_read_struct, (png_structpp png_ptr_ptr, |
|
1578 png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr)); |
|
1579 |
|
1580 /* Free any memory associated with the png_struct and the png_info_structs */ |
|
1581 PNG_EXPORT(65, void, png_destroy_write_struct, (png_structpp png_ptr_ptr, |
|
1582 png_infopp info_ptr_ptr)); |
|
1583 |
|
1584 /* Set the libpng method of handling chunk CRC errors */ |
|
1585 PNG_EXPORT(66, void, png_set_crc_action, |
|
1586 (png_structp png_ptr, int crit_action, int ancil_action)); |
|
1587 |
|
1588 /* Values for png_set_crc_action() say how to handle CRC errors in |
|
1589 * ancillary and critical chunks, and whether to use the data contained |
|
1590 * therein. Note that it is impossible to "discard" data in a critical |
|
1591 * chunk. For versions prior to 0.90, the action was always error/quit, |
|
1592 * whereas in version 0.90 and later, the action for CRC errors in ancillary |
|
1593 * chunks is warn/discard. These values should NOT be changed. |
|
1594 * |
|
1595 * value action:critical action:ancillary |
|
1596 */ |
|
1597 #define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */ |
|
1598 #define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */ |
|
1599 #define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */ |
|
1600 #define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */ |
|
1601 #define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */ |
|
1602 #define PNG_CRC_NO_CHANGE 5 /* use current value use current value */ |
|
1603 |
|
1604 /* These functions give the user control over the scan-line filtering in |
|
1605 * libpng and the compression methods used by zlib. These functions are |
|
1606 * mainly useful for testing, as the defaults should work with most users. |
|
1607 * Those users who are tight on memory or want faster performance at the |
|
1608 * expense of compression can modify them. See the compression library |
|
1609 * header file (zlib.h) for an explination of the compression functions. |
|
1610 */ |
|
1611 |
|
1612 /* Set the filtering method(s) used by libpng. Currently, the only valid |
|
1613 * value for "method" is 0. |
|
1614 */ |
|
1615 PNG_EXPORT(67, void, png_set_filter, |
|
1616 (png_structp png_ptr, int method, int filters)); |
|
1617 |
|
1618 /* Flags for png_set_filter() to say which filters to use. The flags |
|
1619 * are chosen so that they don't conflict with real filter types |
|
1620 * below, in case they are supplied instead of the #defined constants. |
|
1621 * These values should NOT be changed. |
|
1622 */ |
|
1623 #define PNG_NO_FILTERS 0x00 |
|
1624 #define PNG_FILTER_NONE 0x08 |
|
1625 #define PNG_FILTER_SUB 0x10 |
|
1626 #define PNG_FILTER_UP 0x20 |
|
1627 #define PNG_FILTER_AVG 0x40 |
|
1628 #define PNG_FILTER_PAETH 0x80 |
|
1629 #define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \ |
|
1630 PNG_FILTER_AVG | PNG_FILTER_PAETH) |
|
1631 |
|
1632 /* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now. |
|
1633 * These defines should NOT be changed. |
|
1634 */ |
|
1635 #define PNG_FILTER_VALUE_NONE 0 |
|
1636 #define PNG_FILTER_VALUE_SUB 1 |
|
1637 #define PNG_FILTER_VALUE_UP 2 |
|
1638 #define PNG_FILTER_VALUE_AVG 3 |
|
1639 #define PNG_FILTER_VALUE_PAETH 4 |
|
1640 #define PNG_FILTER_VALUE_LAST 5 |
|
1641 |
|
1642 #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* EXPERIMENTAL */ |
|
1643 /* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_ |
|
1644 * defines, either the default (minimum-sum-of-absolute-differences), or |
|
1645 * the experimental method (weighted-minimum-sum-of-absolute-differences). |
|
1646 * |
|
1647 * Weights are factors >= 1.0, indicating how important it is to keep the |
|
1648 * filter type consistent between rows. Larger numbers mean the current |
|
1649 * filter is that many times as likely to be the same as the "num_weights" |
|
1650 * previous filters. This is cumulative for each previous row with a weight. |
|
1651 * There needs to be "num_weights" values in "filter_weights", or it can be |
|
1652 * NULL if the weights aren't being specified. Weights have no influence on |
|
1653 * the selection of the first row filter. Well chosen weights can (in theory) |
|
1654 * improve the compression for a given image. |
|
1655 * |
|
1656 * Costs are factors >= 1.0 indicating the relative decoding costs of a |
|
1657 * filter type. Higher costs indicate more decoding expense, and are |
|
1658 * therefore less likely to be selected over a filter with lower computational |
|
1659 * costs. There needs to be a value in "filter_costs" for each valid filter |
|
1660 * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't |
|
1661 * setting the costs. Costs try to improve the speed of decompression without |
|
1662 * unduly increasing the compressed image size. |
|
1663 * |
|
1664 * A negative weight or cost indicates the default value is to be used, and |
|
1665 * values in the range [0.0, 1.0) indicate the value is to remain unchanged. |
|
1666 * The default values for both weights and costs are currently 1.0, but may |
|
1667 * change if good general weighting/cost heuristics can be found. If both |
|
1668 * the weights and costs are set to 1.0, this degenerates the WEIGHTED method |
|
1669 * to the UNWEIGHTED method, but with added encoding time/computation. |
|
1670 */ |
|
1671 PNG_FP_EXPORT(68, void, png_set_filter_heuristics, (png_structp png_ptr, |
|
1672 int heuristic_method, int num_weights, png_const_doublep filter_weights, |
|
1673 png_const_doublep filter_costs)) |
|
1674 PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed, |
|
1675 (png_structp png_ptr, |
|
1676 int heuristic_method, int num_weights, png_const_fixed_point_p |
|
1677 filter_weights, png_const_fixed_point_p filter_costs)) |
|
1678 #endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */ |
|
1679 |
|
1680 /* Heuristic used for row filter selection. These defines should NOT be |
|
1681 * changed. |
|
1682 */ |
|
1683 #define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */ |
|
1684 #define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */ |
|
1685 #define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */ |
|
1686 #define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */ |
|
1687 |
|
1688 #ifdef PNG_WRITE_SUPPORTED |
|
1689 /* Set the library compression level. Currently, valid values range from |
|
1690 * 0 - 9, corresponding directly to the zlib compression levels 0 - 9 |
|
1691 * (0 - no compression, 9 - "maximal" compression). Note that tests have |
|
1692 * shown that zlib compression levels 3-6 usually perform as well as level 9 |
|
1693 * for PNG images, and do considerably fewer caclulations. In the future, |
|
1694 * these values may not correspond directly to the zlib compression levels. |
|
1695 */ |
|
1696 PNG_EXPORT(69, void, png_set_compression_level, |
|
1697 (png_structp png_ptr, int level)); |
|
1698 |
|
1699 PNG_EXPORT(70, void, png_set_compression_mem_level, (png_structp png_ptr, |
|
1700 int mem_level)); |
|
1701 |
|
1702 PNG_EXPORT(71, void, png_set_compression_strategy, (png_structp png_ptr, |
|
1703 int strategy)); |
|
1704 |
|
1705 /* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a |
|
1706 * smaller value of window_bits if it can do so safely. |
|
1707 */ |
|
1708 PNG_EXPORT(72, void, png_set_compression_window_bits, (png_structp png_ptr, |
|
1709 int window_bits)); |
|
1710 |
|
1711 PNG_EXPORT(73, void, png_set_compression_method, (png_structp png_ptr, |
|
1712 int method)); |
|
1713 #endif |
|
1714 |
|
1715 #ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED |
|
1716 /* Also set zlib parameters for compressing non-IDAT chunks */ |
|
1717 PNG_EXPORT(222, void, png_set_text_compression_level, |
|
1718 (png_structp png_ptr, int level)); |
|
1719 |
|
1720 PNG_EXPORT(223, void, png_set_text_compression_mem_level, (png_structp png_ptr, |
|
1721 int mem_level)); |
|
1722 |
|
1723 PNG_EXPORT(224, void, png_set_text_compression_strategy, (png_structp png_ptr, |
|
1724 int strategy)); |
|
1725 |
|
1726 /* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a |
|
1727 * smaller value of window_bits if it can do so safely. |
|
1728 */ |
|
1729 PNG_EXPORT(225, void, png_set_text_compression_window_bits, (png_structp |
|
1730 png_ptr, int window_bits)); |
|
1731 |
|
1732 PNG_EXPORT(226, void, png_set_text_compression_method, (png_structp png_ptr, |
|
1733 int method)); |
|
1734 #endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */ |
|
1735 |
|
1736 /* These next functions are called for input/output, memory, and error |
|
1737 * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c, |
|
1738 * and call standard C I/O routines such as fread(), fwrite(), and |
|
1739 * fprintf(). These functions can be made to use other I/O routines |
|
1740 * at run time for those applications that need to handle I/O in a |
|
1741 * different manner by calling png_set_???_fn(). See libpng-manual.txt for |
|
1742 * more information. |
|
1743 */ |
|
1744 |
|
1745 #ifdef PNG_STDIO_SUPPORTED |
|
1746 /* Initialize the input/output for the PNG file to the default functions. */ |
|
1747 PNG_EXPORT(74, void, png_init_io, (png_structp png_ptr, png_FILE_p fp)); |
|
1748 #endif |
|
1749 |
|
1750 /* Replace the (error and abort), and warning functions with user |
|
1751 * supplied functions. If no messages are to be printed you must still |
|
1752 * write and use replacement functions. The replacement error_fn should |
|
1753 * still do a longjmp to the last setjmp location if you are using this |
|
1754 * method of error handling. If error_fn or warning_fn is NULL, the |
|
1755 * default function will be used. |
|
1756 */ |
|
1757 |
|
1758 PNG_EXPORT(75, void, png_set_error_fn, |
|
1759 (png_structp png_ptr, png_voidp error_ptr, |
|
1760 png_error_ptr error_fn, png_error_ptr warning_fn)); |
|
1761 |
|
1762 /* Return the user pointer associated with the error functions */ |
|
1763 PNG_EXPORT(76, png_voidp, png_get_error_ptr, (png_const_structp png_ptr)); |
|
1764 |
|
1765 /* Replace the default data output functions with a user supplied one(s). |
|
1766 * If buffered output is not used, then output_flush_fn can be set to NULL. |
|
1767 * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time |
|
1768 * output_flush_fn will be ignored (and thus can be NULL). |
|
1769 * It is probably a mistake to use NULL for output_flush_fn if |
|
1770 * write_data_fn is not also NULL unless you have built libpng with |
|
1771 * PNG_WRITE_FLUSH_SUPPORTED undefined, because in this case libpng's |
|
1772 * default flush function, which uses the standard *FILE structure, will |
|
1773 * be used. |
|
1774 */ |
|
1775 PNG_EXPORT(77, void, png_set_write_fn, (png_structp png_ptr, png_voidp io_ptr, |
|
1776 png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn)); |
|
1777 |
|
1778 /* Replace the default data input function with a user supplied one. */ |
|
1779 PNG_EXPORT(78, void, png_set_read_fn, (png_structp png_ptr, png_voidp io_ptr, |
|
1780 png_rw_ptr read_data_fn)); |
|
1781 |
|
1782 /* Return the user pointer associated with the I/O functions */ |
|
1783 PNG_EXPORT(79, png_voidp, png_get_io_ptr, (png_structp png_ptr)); |
|
1784 |
|
1785 PNG_EXPORT(80, void, png_set_read_status_fn, (png_structp png_ptr, |
|
1786 png_read_status_ptr read_row_fn)); |
|
1787 |
|
1788 PNG_EXPORT(81, void, png_set_write_status_fn, (png_structp png_ptr, |
|
1789 png_write_status_ptr write_row_fn)); |
|
1790 |
|
1791 #ifdef PNG_USER_MEM_SUPPORTED |
|
1792 /* Replace the default memory allocation functions with user supplied one(s). */ |
|
1793 PNG_EXPORT(82, void, png_set_mem_fn, (png_structp png_ptr, png_voidp mem_ptr, |
|
1794 png_malloc_ptr malloc_fn, png_free_ptr free_fn)); |
|
1795 /* Return the user pointer associated with the memory functions */ |
|
1796 PNG_EXPORT(83, png_voidp, png_get_mem_ptr, (png_const_structp png_ptr)); |
|
1797 #endif |
|
1798 |
|
1799 #ifdef PNG_READ_USER_TRANSFORM_SUPPORTED |
|
1800 PNG_EXPORT(84, void, png_set_read_user_transform_fn, (png_structp png_ptr, |
|
1801 png_user_transform_ptr read_user_transform_fn)); |
|
1802 #endif |
|
1803 |
|
1804 #ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED |
|
1805 PNG_EXPORT(85, void, png_set_write_user_transform_fn, (png_structp png_ptr, |
|
1806 png_user_transform_ptr write_user_transform_fn)); |
|
1807 #endif |
|
1808 |
|
1809 #ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED |
|
1810 PNG_EXPORT(86, void, png_set_user_transform_info, (png_structp png_ptr, |
|
1811 png_voidp user_transform_ptr, int user_transform_depth, |
|
1812 int user_transform_channels)); |
|
1813 /* Return the user pointer associated with the user transform functions */ |
|
1814 PNG_EXPORT(87, png_voidp, png_get_user_transform_ptr, |
|
1815 (png_const_structp png_ptr)); |
|
1816 #endif |
|
1817 |
|
1818 #ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED |
|
1819 /* Return information about the row currently being processed. Note that these |
|
1820 * APIs do not fail but will return unexpected results if called outside a user |
|
1821 * transform callback. Also note that when transforming an interlaced image the |
|
1822 * row number is the row number within the sub-image of the interlace pass, so |
|
1823 * the value will increase to the height of the sub-image (not the full image) |
|
1824 * then reset to 0 for the next pass. |
|
1825 * |
|
1826 * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to |
|
1827 * find the output pixel (x,y) given an interlaced sub-image pixel |
|
1828 * (row,col,pass). (See below for these macros.) |
|
1829 */ |
|
1830 PNG_EXPORT(217, png_uint_32, png_get_current_row_number, (png_const_structp)); |
|
1831 PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structp)); |
|
1832 #endif |
|
1833 |
|
1834 #ifdef PNG_USER_CHUNKS_SUPPORTED |
|
1835 PNG_EXPORT(88, void, png_set_read_user_chunk_fn, (png_structp png_ptr, |
|
1836 png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn)); |
|
1837 PNG_EXPORT(89, png_voidp, png_get_user_chunk_ptr, (png_const_structp png_ptr)); |
|
1838 #endif |
|
1839 |
|
1840 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED |
|
1841 /* Sets the function callbacks for the push reader, and a pointer to a |
|
1842 * user-defined structure available to the callback functions. |
|
1843 */ |
|
1844 PNG_EXPORT(90, void, png_set_progressive_read_fn, (png_structp png_ptr, |
|
1845 png_voidp progressive_ptr, png_progressive_info_ptr info_fn, |
|
1846 png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn)); |
|
1847 |
|
1848 /* Returns the user pointer associated with the push read functions */ |
|
1849 PNG_EXPORT(91, png_voidp, png_get_progressive_ptr, (png_const_structp png_ptr)); |
|
1850 |
|
1851 /* Function to be called when data becomes available */ |
|
1852 PNG_EXPORT(92, void, png_process_data, |
|
1853 (png_structp png_ptr, png_infop info_ptr, |
|
1854 png_bytep buffer, png_size_t buffer_size)); |
|
1855 |
|
1856 /* A function which may be called *only* within png_process_data to stop the |
|
1857 * processing of any more data. The function returns the number of bytes |
|
1858 * remaining, excluding any that libpng has cached internally. A subsequent |
|
1859 * call to png_process_data must supply these bytes again. If the argument |
|
1860 * 'save' is set to true the routine will first save all the pending data and |
|
1861 * will always return 0. |
|
1862 */ |
|
1863 PNG_EXPORT(219, png_size_t, png_process_data_pause, (png_structp, int save)); |
|
1864 |
|
1865 /* A function which may be called *only* outside (after) a call to |
|
1866 * png_process_data. It returns the number of bytes of data to skip in the |
|
1867 * input. Normally it will return 0, but if it returns a non-zero value the |
|
1868 * application must skip than number of bytes of input data and pass the |
|
1869 * following data to the next call to png_process_data. |
|
1870 */ |
|
1871 PNG_EXPORT(220, png_uint_32, png_process_data_skip, (png_structp)); |
|
1872 |
|
1873 #ifdef PNG_READ_INTERLACING_SUPPORTED |
|
1874 /* Function that combines rows. 'new_row' is a flag that should come from |
|
1875 * the callback and be non-NULL if anything needs to be done; the library |
|
1876 * stores its own version of the new data internally and ignores the passed |
|
1877 * in value. |
|
1878 */ |
|
1879 PNG_EXPORT(93, void, png_progressive_combine_row, (png_structp png_ptr, |
|
1880 png_bytep old_row, png_const_bytep new_row)); |
|
1881 #endif /* PNG_READ_INTERLACING_SUPPORTED */ |
|
1882 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ |
|
1883 |
|
1884 PNG_EXPORTA(94, png_voidp, png_malloc, |
|
1885 (png_structp png_ptr, png_alloc_size_t size), |
|
1886 PNG_ALLOCATED); |
|
1887 /* Added at libpng version 1.4.0 */ |
|
1888 PNG_EXPORTA(95, png_voidp, png_calloc, |
|
1889 (png_structp png_ptr, png_alloc_size_t size), |
|
1890 PNG_ALLOCATED); |
|
1891 |
|
1892 /* Added at libpng version 1.2.4 */ |
|
1893 PNG_EXPORTA(96, png_voidp, png_malloc_warn, (png_structp png_ptr, |
|
1894 png_alloc_size_t size), PNG_ALLOCATED); |
|
1895 |
|
1896 /* Frees a pointer allocated by png_malloc() */ |
|
1897 PNG_EXPORT(97, void, png_free, (png_structp png_ptr, png_voidp ptr)); |
|
1898 |
|
1899 /* Free data that was allocated internally */ |
|
1900 PNG_EXPORT(98, void, png_free_data, |
|
1901 (png_structp png_ptr, png_infop info_ptr, png_uint_32 free_me, int num)); |
|
1902 |
|
1903 /* Reassign responsibility for freeing existing data, whether allocated |
|
1904 * by libpng or by the application */ |
|
1905 PNG_EXPORT(99, void, png_data_freer, |
|
1906 (png_structp png_ptr, png_infop info_ptr, int freer, png_uint_32 mask)); |
|
1907 |
|
1908 /* Assignments for png_data_freer */ |
|
1909 #define PNG_DESTROY_WILL_FREE_DATA 1 |
|
1910 #define PNG_SET_WILL_FREE_DATA 1 |
|
1911 #define PNG_USER_WILL_FREE_DATA 2 |
|
1912 /* Flags for png_ptr->free_me and info_ptr->free_me */ |
|
1913 #define PNG_FREE_HIST 0x0008 |
|
1914 #define PNG_FREE_ICCP 0x0010 |
|
1915 #define PNG_FREE_SPLT 0x0020 |
|
1916 #define PNG_FREE_ROWS 0x0040 |
|
1917 #define PNG_FREE_PCAL 0x0080 |
|
1918 #define PNG_FREE_SCAL 0x0100 |
|
1919 #define PNG_FREE_UNKN 0x0200 |
|
1920 #define PNG_FREE_LIST 0x0400 |
|
1921 #define PNG_FREE_PLTE 0x1000 |
|
1922 #define PNG_FREE_TRNS 0x2000 |
|
1923 #define PNG_FREE_TEXT 0x4000 |
|
1924 #define PNG_FREE_ALL 0x7fff |
|
1925 #define PNG_FREE_MUL 0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */ |
|
1926 |
|
1927 #ifdef PNG_USER_MEM_SUPPORTED |
|
1928 PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_structp png_ptr, |
|
1929 png_alloc_size_t size), PNG_ALLOCATED); |
|
1930 PNG_EXPORT(101, void, png_free_default, (png_structp png_ptr, png_voidp ptr)); |
|
1931 #endif |
|
1932 |
|
1933 #ifdef PNG_ERROR_TEXT_SUPPORTED |
|
1934 /* Fatal error in PNG image of libpng - can't continue */ |
|
1935 PNG_EXPORTA(102, void, png_error, |
|
1936 (png_structp png_ptr, png_const_charp error_message), |
|
1937 PNG_NORETURN); |
|
1938 |
|
1939 /* The same, but the chunk name is prepended to the error string. */ |
|
1940 PNG_EXPORTA(103, void, png_chunk_error, (png_structp png_ptr, |
|
1941 png_const_charp error_message), PNG_NORETURN); |
|
1942 |
|
1943 #else |
|
1944 /* Fatal error in PNG image of libpng - can't continue */ |
|
1945 PNG_EXPORTA(104, void, png_err, (png_structp png_ptr), PNG_NORETURN); |
|
1946 #endif |
|
1947 |
|
1948 #ifdef PNG_WARNINGS_SUPPORTED |
|
1949 /* Non-fatal error in libpng. Can continue, but may have a problem. */ |
|
1950 PNG_EXPORT(105, void, png_warning, (png_structp png_ptr, |
|
1951 png_const_charp warning_message)); |
|
1952 |
|
1953 /* Non-fatal error in libpng, chunk name is prepended to message. */ |
|
1954 PNG_EXPORT(106, void, png_chunk_warning, (png_structp png_ptr, |
|
1955 png_const_charp warning_message)); |
|
1956 #endif |
|
1957 |
|
1958 #ifdef PNG_BENIGN_ERRORS_SUPPORTED |
|
1959 /* Benign error in libpng. Can continue, but may have a problem. |
|
1960 * User can choose whether to handle as a fatal error or as a warning. */ |
|
1961 # undef png_benign_error |
|
1962 PNG_EXPORT(107, void, png_benign_error, (png_structp png_ptr, |
|
1963 png_const_charp warning_message)); |
|
1964 |
|
1965 /* Same, chunk name is prepended to message. */ |
|
1966 # undef png_chunk_benign_error |
|
1967 PNG_EXPORT(108, void, png_chunk_benign_error, (png_structp png_ptr, |
|
1968 png_const_charp warning_message)); |
|
1969 |
|
1970 PNG_EXPORT(109, void, png_set_benign_errors, |
|
1971 (png_structp png_ptr, int allowed)); |
|
1972 #else |
|
1973 # ifdef PNG_ALLOW_BENIGN_ERRORS |
|
1974 # define png_benign_error png_warning |
|
1975 # define png_chunk_benign_error png_chunk_warning |
|
1976 # else |
|
1977 # define png_benign_error png_error |
|
1978 # define png_chunk_benign_error png_chunk_error |
|
1979 # endif |
|
1980 #endif |
|
1981 |
|
1982 /* The png_set_<chunk> functions are for storing values in the png_info_struct. |
|
1983 * Similarly, the png_get_<chunk> calls are used to read values from the |
|
1984 * png_info_struct, either storing the parameters in the passed variables, or |
|
1985 * setting pointers into the png_info_struct where the data is stored. The |
|
1986 * png_get_<chunk> functions return a non-zero value if the data was available |
|
1987 * in info_ptr, or return zero and do not change any of the parameters if the |
|
1988 * data was not available. |
|
1989 * |
|
1990 * These functions should be used instead of directly accessing png_info |
|
1991 * to avoid problems with future changes in the size and internal layout of |
|
1992 * png_info_struct. |
|
1993 */ |
|
1994 /* Returns "flag" if chunk data is valid in info_ptr. */ |
|
1995 PNG_EXPORT(110, png_uint_32, png_get_valid, |
|
1996 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
1997 png_uint_32 flag)); |
|
1998 |
|
1999 /* Returns number of bytes needed to hold a transformed row. */ |
|
2000 PNG_EXPORT(111, png_size_t, png_get_rowbytes, (png_const_structp png_ptr, |
|
2001 png_const_infop info_ptr)); |
|
2002 |
|
2003 #ifdef PNG_INFO_IMAGE_SUPPORTED |
|
2004 /* Returns row_pointers, which is an array of pointers to scanlines that was |
|
2005 * returned from png_read_png(). |
|
2006 */ |
|
2007 PNG_EXPORT(112, png_bytepp, png_get_rows, |
|
2008 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2009 /* Set row_pointers, which is an array of pointers to scanlines for use |
|
2010 * by png_write_png(). |
|
2011 */ |
|
2012 PNG_EXPORT(113, void, png_set_rows, (png_structp png_ptr, |
|
2013 png_infop info_ptr, png_bytepp row_pointers)); |
|
2014 #endif |
|
2015 |
|
2016 /* Returns number of color channels in image. */ |
|
2017 PNG_EXPORT(114, png_byte, png_get_channels, |
|
2018 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2019 |
|
2020 #ifdef PNG_EASY_ACCESS_SUPPORTED |
|
2021 /* Returns image width in pixels. */ |
|
2022 PNG_EXPORT(115, png_uint_32, png_get_image_width, (png_const_structp png_ptr, |
|
2023 png_const_infop info_ptr)); |
|
2024 |
|
2025 /* Returns image height in pixels. */ |
|
2026 PNG_EXPORT(116, png_uint_32, png_get_image_height, (png_const_structp png_ptr, |
|
2027 png_const_infop info_ptr)); |
|
2028 |
|
2029 /* Returns image bit_depth. */ |
|
2030 PNG_EXPORT(117, png_byte, png_get_bit_depth, |
|
2031 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2032 |
|
2033 /* Returns image color_type. */ |
|
2034 PNG_EXPORT(118, png_byte, png_get_color_type, (png_const_structp png_ptr, |
|
2035 png_const_infop info_ptr)); |
|
2036 |
|
2037 /* Returns image filter_type. */ |
|
2038 PNG_EXPORT(119, png_byte, png_get_filter_type, (png_const_structp png_ptr, |
|
2039 png_const_infop info_ptr)); |
|
2040 |
|
2041 /* Returns image interlace_type. */ |
|
2042 PNG_EXPORT(120, png_byte, png_get_interlace_type, (png_const_structp png_ptr, |
|
2043 png_const_infop info_ptr)); |
|
2044 |
|
2045 /* Returns image compression_type. */ |
|
2046 PNG_EXPORT(121, png_byte, png_get_compression_type, (png_const_structp png_ptr, |
|
2047 png_const_infop info_ptr)); |
|
2048 |
|
2049 /* Returns image resolution in pixels per meter, from pHYs chunk data. */ |
|
2050 PNG_EXPORT(122, png_uint_32, png_get_pixels_per_meter, |
|
2051 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2052 PNG_EXPORT(123, png_uint_32, png_get_x_pixels_per_meter, |
|
2053 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2054 PNG_EXPORT(124, png_uint_32, png_get_y_pixels_per_meter, |
|
2055 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2056 |
|
2057 /* Returns pixel aspect ratio, computed from pHYs chunk data. */ |
|
2058 PNG_FP_EXPORT(125, float, png_get_pixel_aspect_ratio, |
|
2059 (png_const_structp png_ptr, png_const_infop info_ptr)) |
|
2060 PNG_FIXED_EXPORT(210, png_fixed_point, png_get_pixel_aspect_ratio_fixed, |
|
2061 (png_const_structp png_ptr, png_const_infop info_ptr)) |
|
2062 |
|
2063 /* Returns image x, y offset in pixels or microns, from oFFs chunk data. */ |
|
2064 PNG_EXPORT(126, png_int_32, png_get_x_offset_pixels, |
|
2065 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2066 PNG_EXPORT(127, png_int_32, png_get_y_offset_pixels, |
|
2067 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2068 PNG_EXPORT(128, png_int_32, png_get_x_offset_microns, |
|
2069 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2070 PNG_EXPORT(129, png_int_32, png_get_y_offset_microns, |
|
2071 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2072 |
|
2073 #endif /* PNG_EASY_ACCESS_SUPPORTED */ |
|
2074 |
|
2075 /* Returns pointer to signature string read from PNG header */ |
|
2076 PNG_EXPORT(130, png_const_bytep, png_get_signature, |
|
2077 (png_const_structp png_ptr, png_infop info_ptr)); |
|
2078 |
|
2079 #ifdef PNG_bKGD_SUPPORTED |
|
2080 PNG_EXPORT(131, png_uint_32, png_get_bKGD, |
|
2081 (png_const_structp png_ptr, png_infop info_ptr, |
|
2082 png_color_16p *background)); |
|
2083 #endif |
|
2084 |
|
2085 #ifdef PNG_bKGD_SUPPORTED |
|
2086 PNG_EXPORT(132, void, png_set_bKGD, (png_structp png_ptr, png_infop info_ptr, |
|
2087 png_const_color_16p background)); |
|
2088 #endif |
|
2089 |
|
2090 #ifdef PNG_cHRM_SUPPORTED |
|
2091 PNG_FP_EXPORT(133, png_uint_32, png_get_cHRM, (png_const_structp png_ptr, |
|
2092 png_const_infop info_ptr, double *white_x, double *white_y, double *red_x, |
|
2093 double *red_y, double *green_x, double *green_y, double *blue_x, |
|
2094 double *blue_y)) |
|
2095 PNG_FP_EXPORT(230, png_uint_32, png_get_cHRM_XYZ, (png_structp png_ptr, |
|
2096 png_const_infop info_ptr, double *red_X, double *red_Y, double *red_Z, |
|
2097 double *green_X, double *green_Y, double *green_Z, double *blue_X, |
|
2098 double *blue_Y, double *blue_Z)) |
|
2099 #ifdef PNG_FIXED_POINT_SUPPORTED /* Otherwise not implemented */ |
|
2100 PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed, |
|
2101 (png_const_structp png_ptr, |
|
2102 png_const_infop info_ptr, png_fixed_point *int_white_x, |
|
2103 png_fixed_point *int_white_y, png_fixed_point *int_red_x, |
|
2104 png_fixed_point *int_red_y, png_fixed_point *int_green_x, |
|
2105 png_fixed_point *int_green_y, png_fixed_point *int_blue_x, |
|
2106 png_fixed_point *int_blue_y)) |
|
2107 #endif |
|
2108 PNG_FIXED_EXPORT(231, png_uint_32, png_get_cHRM_XYZ_fixed, |
|
2109 (png_structp png_ptr, png_const_infop info_ptr, |
|
2110 png_fixed_point *int_red_X, png_fixed_point *int_red_Y, |
|
2111 png_fixed_point *int_red_Z, png_fixed_point *int_green_X, |
|
2112 png_fixed_point *int_green_Y, png_fixed_point *int_green_Z, |
|
2113 png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y, |
|
2114 png_fixed_point *int_blue_Z)) |
|
2115 #endif |
|
2116 |
|
2117 #ifdef PNG_cHRM_SUPPORTED |
|
2118 PNG_FP_EXPORT(135, void, png_set_cHRM, |
|
2119 (png_structp png_ptr, png_infop info_ptr, |
|
2120 double white_x, double white_y, double red_x, double red_y, double green_x, |
|
2121 double green_y, double blue_x, double blue_y)) |
|
2122 PNG_FP_EXPORT(232, void, png_set_cHRM_XYZ, (png_structp png_ptr, |
|
2123 png_infop info_ptr, double red_X, double red_Y, double red_Z, |
|
2124 double green_X, double green_Y, double green_Z, double blue_X, |
|
2125 double blue_Y, double blue_Z)) |
|
2126 PNG_FIXED_EXPORT(136, void, png_set_cHRM_fixed, (png_structp png_ptr, |
|
2127 png_infop info_ptr, png_fixed_point int_white_x, |
|
2128 png_fixed_point int_white_y, png_fixed_point int_red_x, |
|
2129 png_fixed_point int_red_y, png_fixed_point int_green_x, |
|
2130 png_fixed_point int_green_y, png_fixed_point int_blue_x, |
|
2131 png_fixed_point int_blue_y)) |
|
2132 PNG_FIXED_EXPORT(233, void, png_set_cHRM_XYZ_fixed, (png_structp png_ptr, |
|
2133 png_infop info_ptr, png_fixed_point int_red_X, png_fixed_point int_red_Y, |
|
2134 png_fixed_point int_red_Z, png_fixed_point int_green_X, |
|
2135 png_fixed_point int_green_Y, png_fixed_point int_green_Z, |
|
2136 png_fixed_point int_blue_X, png_fixed_point int_blue_Y, |
|
2137 png_fixed_point int_blue_Z)) |
|
2138 #endif |
|
2139 |
|
2140 #ifdef PNG_gAMA_SUPPORTED |
|
2141 PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA, |
|
2142 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2143 double *file_gamma)) |
|
2144 PNG_FIXED_EXPORT(138, png_uint_32, png_get_gAMA_fixed, |
|
2145 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2146 png_fixed_point *int_file_gamma)) |
|
2147 #endif |
|
2148 |
|
2149 #ifdef PNG_gAMA_SUPPORTED |
|
2150 PNG_FP_EXPORT(139, void, png_set_gAMA, (png_structp png_ptr, |
|
2151 png_infop info_ptr, double file_gamma)) |
|
2152 PNG_FIXED_EXPORT(140, void, png_set_gAMA_fixed, (png_structp png_ptr, |
|
2153 png_infop info_ptr, png_fixed_point int_file_gamma)) |
|
2154 #endif |
|
2155 |
|
2156 #ifdef PNG_hIST_SUPPORTED |
|
2157 PNG_EXPORT(141, png_uint_32, png_get_hIST, |
|
2158 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2159 png_uint_16p *hist)); |
|
2160 #endif |
|
2161 |
|
2162 #ifdef PNG_hIST_SUPPORTED |
|
2163 PNG_EXPORT(142, void, png_set_hIST, (png_structp png_ptr, |
|
2164 png_infop info_ptr, png_const_uint_16p hist)); |
|
2165 #endif |
|
2166 |
|
2167 PNG_EXPORT(143, png_uint_32, png_get_IHDR, |
|
2168 (png_structp png_ptr, png_infop info_ptr, |
|
2169 png_uint_32 *width, png_uint_32 *height, int *bit_depth, int *color_type, |
|
2170 int *interlace_method, int *compression_method, int *filter_method)); |
|
2171 |
|
2172 PNG_EXPORT(144, void, png_set_IHDR, |
|
2173 (png_structp png_ptr, png_infop info_ptr, |
|
2174 png_uint_32 width, png_uint_32 height, int bit_depth, int color_type, |
|
2175 int interlace_method, int compression_method, int filter_method)); |
|
2176 |
|
2177 #ifdef PNG_oFFs_SUPPORTED |
|
2178 PNG_EXPORT(145, png_uint_32, png_get_oFFs, |
|
2179 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2180 png_int_32 *offset_x, png_int_32 *offset_y, int *unit_type)); |
|
2181 #endif |
|
2182 |
|
2183 #ifdef PNG_oFFs_SUPPORTED |
|
2184 PNG_EXPORT(146, void, png_set_oFFs, |
|
2185 (png_structp png_ptr, png_infop info_ptr, |
|
2186 png_int_32 offset_x, png_int_32 offset_y, int unit_type)); |
|
2187 #endif |
|
2188 |
|
2189 #ifdef PNG_pCAL_SUPPORTED |
|
2190 PNG_EXPORT(147, png_uint_32, png_get_pCAL, |
|
2191 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2192 png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type, |
|
2193 int *nparams, |
|
2194 png_charp *units, png_charpp *params)); |
|
2195 #endif |
|
2196 |
|
2197 #ifdef PNG_pCAL_SUPPORTED |
|
2198 PNG_EXPORT(148, void, png_set_pCAL, (png_structp png_ptr, |
|
2199 png_infop info_ptr, |
|
2200 png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type, |
|
2201 int nparams, png_const_charp units, png_charpp params)); |
|
2202 #endif |
|
2203 |
|
2204 #ifdef PNG_pHYs_SUPPORTED |
|
2205 PNG_EXPORT(149, png_uint_32, png_get_pHYs, |
|
2206 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2207 png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)); |
|
2208 #endif |
|
2209 |
|
2210 #ifdef PNG_pHYs_SUPPORTED |
|
2211 PNG_EXPORT(150, void, png_set_pHYs, |
|
2212 (png_structp png_ptr, png_infop info_ptr, |
|
2213 png_uint_32 res_x, png_uint_32 res_y, int unit_type)); |
|
2214 #endif |
|
2215 |
|
2216 PNG_EXPORT(151, png_uint_32, png_get_PLTE, |
|
2217 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2218 png_colorp *palette, int *num_palette)); |
|
2219 |
|
2220 PNG_EXPORT(152, void, png_set_PLTE, |
|
2221 (png_structp png_ptr, png_infop info_ptr, |
|
2222 png_const_colorp palette, int num_palette)); |
|
2223 |
|
2224 #ifdef PNG_sBIT_SUPPORTED |
|
2225 PNG_EXPORT(153, png_uint_32, png_get_sBIT, |
|
2226 (png_const_structp png_ptr, png_infop info_ptr, |
|
2227 png_color_8p *sig_bit)); |
|
2228 #endif |
|
2229 |
|
2230 #ifdef PNG_sBIT_SUPPORTED |
|
2231 PNG_EXPORT(154, void, png_set_sBIT, |
|
2232 (png_structp png_ptr, png_infop info_ptr, png_const_color_8p sig_bit)); |
|
2233 #endif |
|
2234 |
|
2235 #ifdef PNG_sRGB_SUPPORTED |
|
2236 PNG_EXPORT(155, png_uint_32, png_get_sRGB, (png_const_structp png_ptr, |
|
2237 png_const_infop info_ptr, int *file_srgb_intent)); |
|
2238 #endif |
|
2239 |
|
2240 #ifdef PNG_sRGB_SUPPORTED |
|
2241 PNG_EXPORT(156, void, png_set_sRGB, |
|
2242 (png_structp png_ptr, png_infop info_ptr, int srgb_intent)); |
|
2243 PNG_EXPORT(157, void, png_set_sRGB_gAMA_and_cHRM, (png_structp png_ptr, |
|
2244 png_infop info_ptr, int srgb_intent)); |
|
2245 #endif |
|
2246 |
|
2247 #ifdef PNG_iCCP_SUPPORTED |
|
2248 PNG_EXPORT(158, png_uint_32, png_get_iCCP, |
|
2249 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2250 png_charpp name, int *compression_type, png_bytepp profile, |
|
2251 png_uint_32 *proflen)); |
|
2252 #endif |
|
2253 |
|
2254 #ifdef PNG_iCCP_SUPPORTED |
|
2255 PNG_EXPORT(159, void, png_set_iCCP, |
|
2256 (png_structp png_ptr, png_infop info_ptr, |
|
2257 png_const_charp name, int compression_type, png_const_bytep profile, |
|
2258 png_uint_32 proflen)); |
|
2259 #endif |
|
2260 |
|
2261 #ifdef PNG_sPLT_SUPPORTED |
|
2262 PNG_EXPORT(160, png_uint_32, png_get_sPLT, |
|
2263 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2264 png_sPLT_tpp entries)); |
|
2265 #endif |
|
2266 |
|
2267 #ifdef PNG_sPLT_SUPPORTED |
|
2268 PNG_EXPORT(161, void, png_set_sPLT, |
|
2269 (png_structp png_ptr, png_infop info_ptr, |
|
2270 png_const_sPLT_tp entries, int nentries)); |
|
2271 #endif |
|
2272 |
|
2273 #ifdef PNG_TEXT_SUPPORTED |
|
2274 /* png_get_text also returns the number of text chunks in *num_text */ |
|
2275 PNG_EXPORT(162, png_uint_32, png_get_text, |
|
2276 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2277 png_textp *text_ptr, int *num_text)); |
|
2278 #endif |
|
2279 |
|
2280 /* Note while png_set_text() will accept a structure whose text, |
|
2281 * language, and translated keywords are NULL pointers, the structure |
|
2282 * returned by png_get_text will always contain regular |
|
2283 * zero-terminated C strings. They might be empty strings but |
|
2284 * they will never be NULL pointers. |
|
2285 */ |
|
2286 |
|
2287 #ifdef PNG_TEXT_SUPPORTED |
|
2288 PNG_EXPORT(163, void, png_set_text, |
|
2289 (png_structp png_ptr, png_infop info_ptr, |
|
2290 png_const_textp text_ptr, int num_text)); |
|
2291 #endif |
|
2292 |
|
2293 #ifdef PNG_tIME_SUPPORTED |
|
2294 PNG_EXPORT(164, png_uint_32, png_get_tIME, |
|
2295 (png_const_structp png_ptr, png_infop info_ptr, png_timep *mod_time)); |
|
2296 #endif |
|
2297 |
|
2298 #ifdef PNG_tIME_SUPPORTED |
|
2299 PNG_EXPORT(165, void, png_set_tIME, |
|
2300 (png_structp png_ptr, png_infop info_ptr, png_const_timep mod_time)); |
|
2301 #endif |
|
2302 |
|
2303 #ifdef PNG_tRNS_SUPPORTED |
|
2304 PNG_EXPORT(166, png_uint_32, png_get_tRNS, |
|
2305 (png_const_structp png_ptr, png_infop info_ptr, |
|
2306 png_bytep *trans_alpha, int *num_trans, png_color_16p *trans_color)); |
|
2307 #endif |
|
2308 |
|
2309 #ifdef PNG_tRNS_SUPPORTED |
|
2310 PNG_EXPORT(167, void, png_set_tRNS, |
|
2311 (png_structp png_ptr, png_infop info_ptr, |
|
2312 png_const_bytep trans_alpha, int num_trans, |
|
2313 png_const_color_16p trans_color)); |
|
2314 #endif |
|
2315 |
|
2316 #ifdef PNG_sCAL_SUPPORTED |
|
2317 PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL, |
|
2318 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2319 int *unit, double *width, double *height)) |
|
2320 #ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED |
|
2321 /* NOTE: this API is currently implemented using floating point arithmetic, |
|
2322 * consequently it can only be used on systems with floating point support. |
|
2323 * In any case the range of values supported by png_fixed_point is small and it |
|
2324 * is highly recommended that png_get_sCAL_s be used instead. |
|
2325 */ |
|
2326 PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed, |
|
2327 (png_structp png_ptr, png_const_infop info_ptr, int *unit, |
|
2328 png_fixed_point *width, |
|
2329 png_fixed_point *height)) |
|
2330 #endif |
|
2331 PNG_EXPORT(169, png_uint_32, png_get_sCAL_s, |
|
2332 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2333 int *unit, png_charpp swidth, png_charpp sheight)); |
|
2334 |
|
2335 PNG_FP_EXPORT(170, void, png_set_sCAL, |
|
2336 (png_structp png_ptr, png_infop info_ptr, |
|
2337 int unit, double width, double height)) |
|
2338 PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_structp png_ptr, |
|
2339 png_infop info_ptr, int unit, png_fixed_point width, |
|
2340 png_fixed_point height)) |
|
2341 PNG_EXPORT(171, void, png_set_sCAL_s, |
|
2342 (png_structp png_ptr, png_infop info_ptr, |
|
2343 int unit, png_const_charp swidth, png_const_charp sheight)); |
|
2344 #endif /* PNG_sCAL_SUPPORTED */ |
|
2345 |
|
2346 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED |
|
2347 /* Provide a list of chunks and how they are to be handled, if the built-in |
|
2348 handling or default unknown chunk handling is not desired. Any chunks not |
|
2349 listed will be handled in the default manner. The IHDR and IEND chunks |
|
2350 must not be listed. Because this turns off the default handling for chunks |
|
2351 that would otherwise be recognized the behavior of libpng transformations may |
|
2352 well become incorrect! |
|
2353 keep = 0: PNG_HANDLE_CHUNK_AS_DEFAULT: follow default behavior |
|
2354 = 1: PNG_HANDLE_CHUNK_NEVER: do not keep |
|
2355 = 2: PNG_HANDLE_CHUNK_IF_SAFE: keep only if safe-to-copy |
|
2356 = 3: PNG_HANDLE_CHUNK_ALWAYS: keep even if unsafe-to-copy |
|
2357 */ |
|
2358 PNG_EXPORT(172, void, png_set_keep_unknown_chunks, |
|
2359 (png_structp png_ptr, int keep, |
|
2360 png_const_bytep chunk_list, int num_chunks)); |
|
2361 |
|
2362 /* The handling code is returned; the result is therefore true (non-zero) if |
|
2363 * special handling is required, false for the default handling. |
|
2364 */ |
|
2365 PNG_EXPORT(173, int, png_handle_as_unknown, (png_structp png_ptr, |
|
2366 png_const_bytep chunk_name)); |
|
2367 #endif |
|
2368 #ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED |
|
2369 PNG_EXPORT(174, void, png_set_unknown_chunks, (png_structp png_ptr, |
|
2370 png_infop info_ptr, png_const_unknown_chunkp unknowns, |
|
2371 int num_unknowns)); |
|
2372 PNG_EXPORT(175, void, png_set_unknown_chunk_location, |
|
2373 (png_structp png_ptr, png_infop info_ptr, int chunk, int location)); |
|
2374 PNG_EXPORT(176, int, png_get_unknown_chunks, (png_const_structp png_ptr, |
|
2375 png_const_infop info_ptr, png_unknown_chunkpp entries)); |
|
2376 #endif |
|
2377 |
|
2378 /* Png_free_data() will turn off the "valid" flag for anything it frees. |
|
2379 * If you need to turn it off for a chunk that your application has freed, |
|
2380 * you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); |
|
2381 */ |
|
2382 PNG_EXPORT(177, void, png_set_invalid, |
|
2383 (png_structp png_ptr, png_infop info_ptr, int mask)); |
|
2384 |
|
2385 #ifdef PNG_INFO_IMAGE_SUPPORTED |
|
2386 /* The "params" pointer is currently not used and is for future expansion. */ |
|
2387 PNG_EXPORT(178, void, png_read_png, (png_structp png_ptr, png_infop info_ptr, |
|
2388 int transforms, png_voidp params)); |
|
2389 PNG_EXPORT(179, void, png_write_png, (png_structp png_ptr, png_infop info_ptr, |
|
2390 int transforms, png_voidp params)); |
|
2391 #endif |
|
2392 |
|
2393 PNG_EXPORT(180, png_const_charp, png_get_copyright, |
|
2394 (png_const_structp png_ptr)); |
|
2395 PNG_EXPORT(181, png_const_charp, png_get_header_ver, |
|
2396 (png_const_structp png_ptr)); |
|
2397 PNG_EXPORT(182, png_const_charp, png_get_header_version, |
|
2398 (png_const_structp png_ptr)); |
|
2399 PNG_EXPORT(183, png_const_charp, png_get_libpng_ver, |
|
2400 (png_const_structp png_ptr)); |
|
2401 |
|
2402 #ifdef PNG_MNG_FEATURES_SUPPORTED |
|
2403 PNG_EXPORT(184, png_uint_32, png_permit_mng_features, (png_structp png_ptr, |
|
2404 png_uint_32 mng_features_permitted)); |
|
2405 #endif |
|
2406 |
|
2407 /* For use in png_set_keep_unknown, added to version 1.2.6 */ |
|
2408 #define PNG_HANDLE_CHUNK_AS_DEFAULT 0 |
|
2409 #define PNG_HANDLE_CHUNK_NEVER 1 |
|
2410 #define PNG_HANDLE_CHUNK_IF_SAFE 2 |
|
2411 #define PNG_HANDLE_CHUNK_ALWAYS 3 |
|
2412 |
|
2413 /* Strip the prepended error numbers ("#nnn ") from error and warning |
|
2414 * messages before passing them to the error or warning handler. |
|
2415 */ |
|
2416 #ifdef PNG_ERROR_NUMBERS_SUPPORTED |
|
2417 PNG_EXPORT(185, void, png_set_strip_error_numbers, |
|
2418 (png_structp png_ptr, |
|
2419 png_uint_32 strip_mode)); |
|
2420 #endif |
|
2421 |
|
2422 /* Added in libpng-1.2.6 */ |
|
2423 #ifdef PNG_SET_USER_LIMITS_SUPPORTED |
|
2424 PNG_EXPORT(186, void, png_set_user_limits, (png_structp png_ptr, |
|
2425 png_uint_32 user_width_max, png_uint_32 user_height_max)); |
|
2426 PNG_EXPORT(187, png_uint_32, png_get_user_width_max, |
|
2427 (png_const_structp png_ptr)); |
|
2428 PNG_EXPORT(188, png_uint_32, png_get_user_height_max, |
|
2429 (png_const_structp png_ptr)); |
|
2430 /* Added in libpng-1.4.0 */ |
|
2431 PNG_EXPORT(189, void, png_set_chunk_cache_max, (png_structp png_ptr, |
|
2432 png_uint_32 user_chunk_cache_max)); |
|
2433 PNG_EXPORT(190, png_uint_32, png_get_chunk_cache_max, |
|
2434 (png_const_structp png_ptr)); |
|
2435 /* Added in libpng-1.4.1 */ |
|
2436 PNG_EXPORT(191, void, png_set_chunk_malloc_max, (png_structp png_ptr, |
|
2437 png_alloc_size_t user_chunk_cache_max)); |
|
2438 PNG_EXPORT(192, png_alloc_size_t, png_get_chunk_malloc_max, |
|
2439 (png_const_structp png_ptr)); |
|
2440 #endif |
|
2441 |
|
2442 #if defined(PNG_INCH_CONVERSIONS_SUPPORTED) |
|
2443 PNG_EXPORT(193, png_uint_32, png_get_pixels_per_inch, |
|
2444 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2445 |
|
2446 PNG_EXPORT(194, png_uint_32, png_get_x_pixels_per_inch, |
|
2447 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2448 |
|
2449 PNG_EXPORT(195, png_uint_32, png_get_y_pixels_per_inch, |
|
2450 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2451 |
|
2452 PNG_FP_EXPORT(196, float, png_get_x_offset_inches, |
|
2453 (png_const_structp png_ptr, png_const_infop info_ptr)) |
|
2454 #ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ |
|
2455 PNG_FIXED_EXPORT(211, png_fixed_point, png_get_x_offset_inches_fixed, |
|
2456 (png_structp png_ptr, png_const_infop info_ptr)) |
|
2457 #endif |
|
2458 |
|
2459 PNG_FP_EXPORT(197, float, png_get_y_offset_inches, (png_const_structp png_ptr, |
|
2460 png_const_infop info_ptr)) |
|
2461 #ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ |
|
2462 PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed, |
|
2463 (png_structp png_ptr, png_const_infop info_ptr)) |
|
2464 #endif |
|
2465 |
|
2466 # ifdef PNG_pHYs_SUPPORTED |
|
2467 PNG_EXPORT(198, png_uint_32, png_get_pHYs_dpi, (png_const_structp png_ptr, |
|
2468 png_const_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, |
|
2469 int *unit_type)); |
|
2470 # endif /* PNG_pHYs_SUPPORTED */ |
|
2471 #endif /* PNG_INCH_CONVERSIONS_SUPPORTED */ |
|
2472 |
|
2473 /* Added in libpng-1.4.0 */ |
|
2474 #ifdef PNG_IO_STATE_SUPPORTED |
|
2475 PNG_EXPORT(199, png_uint_32, png_get_io_state, (png_structp png_ptr)); |
|
2476 |
|
2477 PNG_EXPORTA(200, png_const_bytep, png_get_io_chunk_name, |
|
2478 (png_structp png_ptr), PNG_DEPRECATED); |
|
2479 PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type, |
|
2480 (png_const_structp png_ptr)); |
|
2481 |
|
2482 /* The flags returned by png_get_io_state() are the following: */ |
|
2483 # define PNG_IO_NONE 0x0000 /* no I/O at this moment */ |
|
2484 # define PNG_IO_READING 0x0001 /* currently reading */ |
|
2485 # define PNG_IO_WRITING 0x0002 /* currently writing */ |
|
2486 # define PNG_IO_SIGNATURE 0x0010 /* currently at the file signature */ |
|
2487 # define PNG_IO_CHUNK_HDR 0x0020 /* currently at the chunk header */ |
|
2488 # define PNG_IO_CHUNK_DATA 0x0040 /* currently at the chunk data */ |
|
2489 # define PNG_IO_CHUNK_CRC 0x0080 /* currently at the chunk crc */ |
|
2490 # define PNG_IO_MASK_OP 0x000f /* current operation: reading/writing */ |
|
2491 # define PNG_IO_MASK_LOC 0x00f0 /* current location: sig/hdr/data/crc */ |
|
2492 #endif /* ?PNG_IO_STATE_SUPPORTED */ |
|
2493 |
|
2494 /* Interlace support. The following macros are always defined so that if |
|
2495 * libpng interlace handling is turned off the macros may be used to handle |
|
2496 * interlaced images within the application. |
|
2497 */ |
|
2498 #define PNG_INTERLACE_ADAM7_PASSES 7 |
|
2499 |
|
2500 /* Two macros to return the first row and first column of the original, |
|
2501 * full, image which appears in a given pass. 'pass' is in the range 0 |
|
2502 * to 6 and the result is in the range 0 to 7. |
|
2503 */ |
|
2504 #define PNG_PASS_START_ROW(pass) (((1&~(pass))<<(3-((pass)>>1)))&7) |
|
2505 #define PNG_PASS_START_COL(pass) (((1& (pass))<<(3-(((pass)+1)>>1)))&7) |
|
2506 |
|
2507 /* A macro to return the offset between pixels in the output row for a pair of |
|
2508 * pixels in the input - effectively the inverse of the 'COL_SHIFT' macro that |
|
2509 * follows. Note that ROW_OFFSET is the offset from one row to the next whereas |
|
2510 * COL_OFFSET is from one column to the next, within a row. |
|
2511 */ |
|
2512 #define PNG_PASS_ROW_OFFSET(pass) ((pass)>2?(8>>(((pass)-1)>>1)):8) |
|
2513 #define PNG_PASS_COL_OFFSET(pass) (1<<((7-(pass))>>1)) |
|
2514 |
|
2515 /* Two macros to help evaluate the number of rows or columns in each |
|
2516 * pass. This is expressed as a shift - effectively log2 of the number or |
|
2517 * rows or columns in each 8x8 tile of the original image. |
|
2518 */ |
|
2519 #define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3) |
|
2520 #define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3) |
|
2521 |
|
2522 /* Hence two macros to determine the number of rows or columns in a given |
|
2523 * pass of an image given its height or width. In fact these macros may |
|
2524 * return non-zero even though the sub-image is empty, because the other |
|
2525 * dimension may be empty for a small image. |
|
2526 */ |
|
2527 #define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\ |
|
2528 -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass)) |
|
2529 #define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\ |
|
2530 -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass)) |
|
2531 |
|
2532 /* For the reader row callbacks (both progressive and sequential) it is |
|
2533 * necessary to find the row in the output image given a row in an interlaced |
|
2534 * image, so two more macros: |
|
2535 */ |
|
2536 #define PNG_ROW_FROM_PASS_ROW(yIn, pass) \ |
|
2537 (((yIn)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass)) |
|
2538 #define PNG_COL_FROM_PASS_COL(xIn, pass) \ |
|
2539 (((xIn)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass)) |
|
2540 |
|
2541 /* Two macros which return a boolean (0 or 1) saying whether the given row |
|
2542 * or column is in a particular pass. These use a common utility macro that |
|
2543 * returns a mask for a given pass - the offset 'off' selects the row or |
|
2544 * column version. The mask has the appropriate bit set for each column in |
|
2545 * the tile. |
|
2546 */ |
|
2547 #define PNG_PASS_MASK(pass,off) ( \ |
|
2548 ((0x110145AF>>(((7-(off))-(pass))<<2)) & 0xF) | \ |
|
2549 ((0x01145AF0>>(((7-(off))-(pass))<<2)) & 0xF0)) |
|
2550 |
|
2551 #define PNG_ROW_IN_INTERLACE_PASS(y, pass) \ |
|
2552 ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1) |
|
2553 #define PNG_COL_IN_INTERLACE_PASS(x, pass) \ |
|
2554 ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1) |
|
2555 |
|
2556 #ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED |
|
2557 /* With these routines we avoid an integer divide, which will be slower on |
|
2558 * most machines. However, it does take more operations than the corresponding |
|
2559 * divide method, so it may be slower on a few RISC systems. There are two |
|
2560 * shifts (by 8 or 16 bits) and an addition, versus a single integer divide. |
|
2561 * |
|
2562 * Note that the rounding factors are NOT supposed to be the same! 128 and |
|
2563 * 32768 are correct for the NODIV code; 127 and 32767 are correct for the |
|
2564 * standard method. |
|
2565 * |
|
2566 * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ] |
|
2567 */ |
|
2568 |
|
2569 /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */ |
|
2570 |
|
2571 # define png_composite(composite, fg, alpha, bg) \ |
|
2572 { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) \ |
|
2573 * (png_uint_16)(alpha) \ |
|
2574 + (png_uint_16)(bg)*(png_uint_16)(255 \ |
|
2575 - (png_uint_16)(alpha)) + 128); \ |
|
2576 (composite) = (png_byte)((temp + (temp >> 8)) >> 8); } |
|
2577 |
|
2578 # define png_composite_16(composite, fg, alpha, bg) \ |
|
2579 { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) \ |
|
2580 * (png_uint_32)(alpha) \ |
|
2581 + (png_uint_32)(bg)*(65535 \ |
|
2582 - (png_uint_32)(alpha)) + 32768); \ |
|
2583 (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); } |
|
2584 |
|
2585 #else /* Standard method using integer division */ |
|
2586 |
|
2587 # define png_composite(composite, fg, alpha, bg) \ |
|
2588 (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \ |
|
2589 (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \ |
|
2590 127) / 255) |
|
2591 |
|
2592 # define png_composite_16(composite, fg, alpha, bg) \ |
|
2593 (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \ |
|
2594 (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) + \ |
|
2595 32767) / 65535) |
|
2596 #endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */ |
|
2597 |
|
2598 #ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED |
|
2599 PNG_EXPORT(201, png_uint_32, png_get_uint_32, (png_const_bytep buf)); |
|
2600 PNG_EXPORT(202, png_uint_16, png_get_uint_16, (png_const_bytep buf)); |
|
2601 PNG_EXPORT(203, png_int_32, png_get_int_32, (png_const_bytep buf)); |
|
2602 #endif |
|
2603 |
|
2604 PNG_EXPORT(204, png_uint_32, png_get_uint_31, (png_structp png_ptr, |
|
2605 png_const_bytep buf)); |
|
2606 /* No png_get_int_16 -- may be added if there's a real need for it. */ |
|
2607 |
|
2608 /* Place a 32-bit number into a buffer in PNG byte order (big-endian). */ |
|
2609 #ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED |
|
2610 PNG_EXPORT(205, void, png_save_uint_32, (png_bytep buf, png_uint_32 i)); |
|
2611 #endif |
|
2612 #ifdef PNG_SAVE_INT_32_SUPPORTED |
|
2613 PNG_EXPORT(206, void, png_save_int_32, (png_bytep buf, png_int_32 i)); |
|
2614 #endif |
|
2615 |
|
2616 /* Place a 16-bit number into a buffer in PNG byte order. |
|
2617 * The parameter is declared unsigned int, not png_uint_16, |
|
2618 * just to avoid potential problems on pre-ANSI C compilers. |
|
2619 */ |
|
2620 #ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED |
|
2621 PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i)); |
|
2622 /* No png_save_int_16 -- may be added if there's a real need for it. */ |
|
2623 #endif |
|
2624 |
|
2625 #ifdef PNG_USE_READ_MACROS |
|
2626 /* Inline macros to do direct reads of bytes from the input buffer. |
|
2627 * The png_get_int_32() routine assumes we are using two's complement |
|
2628 * format for negative values, which is almost certainly true. |
|
2629 */ |
|
2630 # define png_get_uint_32(buf) \ |
|
2631 (((png_uint_32)(*(buf)) << 24) + \ |
|
2632 ((png_uint_32)(*((buf) + 1)) << 16) + \ |
|
2633 ((png_uint_32)(*((buf) + 2)) << 8) + \ |
|
2634 ((png_uint_32)(*((buf) + 3)))) |
|
2635 |
|
2636 /* From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the |
|
2637 * function) incorrectly returned a value of type png_uint_32. |
|
2638 */ |
|
2639 # define png_get_uint_16(buf) \ |
|
2640 ((png_uint_16) \ |
|
2641 (((unsigned int)(*(buf)) << 8) + \ |
|
2642 ((unsigned int)(*((buf) + 1))))) |
|
2643 |
|
2644 # define png_get_int_32(buf) \ |
|
2645 ((png_int_32)((*(buf) & 0x80) \ |
|
2646 ? -((png_int_32)((png_get_uint_32(buf) ^ 0xffffffffL) + 1)) \ |
|
2647 : (png_int_32)png_get_uint_32(buf))) |
|
2648 #endif |
|
2649 |
|
2650 #if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \ |
|
2651 defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED) |
|
2652 PNG_EXPORT(234, void, png_set_check_for_invalid_index, (png_structp png_ptr, |
|
2653 int allowed)); |
|
2654 #endif |
|
2655 |
|
2656 /* Maintainer: Put new public prototypes here ^, in libpng.3, and project |
|
2657 * defs |
|
2658 */ |
|
2659 |
|
2660 /* The last ordinal number (this is the *last* one already used; the next |
|
2661 * one to use is one more than this.) Maintainer, remember to add an entry to |
|
2662 * scripts/symbols.def as well. |
|
2663 */ |
|
2664 #ifdef PNG_EXPORT_LAST_ORDINAL |
|
2665 PNG_EXPORT_LAST_ORDINAL(234); |
|
2666 #endif |
|
2667 |
|
2668 #ifdef __cplusplus |
|
2669 } |
|
2670 #endif |
|
2671 |
|
2672 #endif /* PNG_VERSION_INFO_ONLY */ |
|
2673 /* Do not put anything past this line */ |
|
2674 #endif /* PNG_H */ |