diff -r e353ca78d28b -r f7e49eff3708 misc/libtremor/floor0.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/misc/libtremor/floor0.c	Sun Apr 24 22:57:57 2011 +0200
@@ -0,0 +1,435 @@
+/********************************************************************
+ *                                                                  *
+ * THIS FILE IS PART OF THE OggVorbis 'TREMOR' CODEC SOURCE CODE.   *
+ *                                                                  *
+ * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
+ * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
+ * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
+ *                                                                  *
+ * THE OggVorbis 'TREMOR' SOURCE CODE IS (C) COPYRIGHT 1994-2002    *
+ * BY THE Xiph.Org FOUNDATION http://www.xiph.org/                  *
+ *                                                                  *
+ ********************************************************************
+
+ function: floor backend 0 implementation
+
+ ********************************************************************/
+
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+#include "ogg.h"
+#include "ivorbiscodec.h"
+#include "codec_internal.h"
+#include "registry.h"
+#include "codebook.h"
+#include "misc.h"
+#include "block.h"
+
+#define LSP_FRACBITS 14
+
+typedef struct {
+  long n;
+  int ln;
+  int  m;
+  int *linearmap;
+
+  vorbis_info_floor0 *vi;
+  ogg_int32_t *lsp_look;
+
+} vorbis_look_floor0;
+
+/*************** LSP decode ********************/
+
+#include "lsp_lookup.h"
+
+/* interpolated 1./sqrt(p) where .5 <= a < 1. (.100000... to .111111...) in
+   16.16 format 
+   returns in m.8 format */
+
+static long ADJUST_SQRT2[2]={8192,5792};
+STIN ogg_int32_t vorbis_invsqlook_i(long a,long e){
+  long i=(a&0x7fff)>>(INVSQ_LOOKUP_I_SHIFT-1); 
+  long d=a&INVSQ_LOOKUP_I_MASK;                              /*  0.10 */
+  long val=INVSQ_LOOKUP_I[i]-                                /*  1.16 */
+    ((INVSQ_LOOKUP_IDel[i]*d)>>INVSQ_LOOKUP_I_SHIFT);        /* result 1.16 */
+  val*=ADJUST_SQRT2[e&1];
+  e=(e>>1)+21;
+  return(val>>e);
+}
+
+/* interpolated lookup based fromdB function, domain -140dB to 0dB only */
+/* a is in n.12 format */
+STIN ogg_int32_t vorbis_fromdBlook_i(long a){
+  int i=(-a)>>(12-FROMdB2_SHIFT);
+  if(i<0) return 0x7fffffff;
+  if(i>=(FROMdB_LOOKUP_SZ<<FROMdB_SHIFT))return 0;
+  
+  return FROMdB_LOOKUP[i>>FROMdB_SHIFT] * FROMdB2_LOOKUP[i&FROMdB2_MASK];
+}
+
+/* interpolated lookup based cos function, domain 0 to PI only */
+/* a is in 0.16 format, where 0==0, 2^^16-1==PI, return 0.14 */
+STIN ogg_int32_t vorbis_coslook_i(long a){
+  int i=a>>COS_LOOKUP_I_SHIFT;
+  int d=a&COS_LOOKUP_I_MASK;
+  return COS_LOOKUP_I[i]- ((d*(COS_LOOKUP_I[i]-COS_LOOKUP_I[i+1]))>>
+			   COS_LOOKUP_I_SHIFT);
+}
+
+/* interpolated lookup based cos function */
+/* a is in 0.16 format, where 0==0, 2^^16==PI, return .LSP_FRACBITS */
+STIN ogg_int32_t vorbis_coslook2_i(long a){
+  a=a&0x1ffff;
+
+  if(a>0x10000)a=0x20000-a;
+  {               
+    int i=a>>COS_LOOKUP_I_SHIFT;
+    int d=a&COS_LOOKUP_I_MASK;
+    a=((COS_LOOKUP_I[i]<<COS_LOOKUP_I_SHIFT)-
+       d*(COS_LOOKUP_I[i]-COS_LOOKUP_I[i+1]))>>
+      (COS_LOOKUP_I_SHIFT-LSP_FRACBITS+14);
+  }
+  
+  return(a);
+}
+
+static const int barklook[28]={
+  0,100,200,301,          405,516,635,766,
+  912,1077,1263,1476,     1720,2003,2333,2721,
+  3184,3742,4428,5285,    6376,7791,9662,12181,
+  15624,20397,27087,36554
+};
+
+/* used in init only; interpolate the long way */
+STIN ogg_int32_t toBARK(int n){
+  int i;
+  for(i=0;i<27;i++) 
+    if(n>=barklook[i] && n<barklook[i+1])break;
+  
+  if(i==27){
+    return 27<<15;
+  }else{
+    int gap=barklook[i+1]-barklook[i];
+    int del=n-barklook[i];
+
+    return((i<<15)+((del<<15)/gap));
+  }
+}
+
+static const unsigned char MLOOP_1[64]={
+   0,10,11,11, 12,12,12,12, 13,13,13,13, 13,13,13,13,
+  14,14,14,14, 14,14,14,14, 14,14,14,14, 14,14,14,14,
+  15,15,15,15, 15,15,15,15, 15,15,15,15, 15,15,15,15,
+  15,15,15,15, 15,15,15,15, 15,15,15,15, 15,15,15,15,
+};
+
+static const unsigned char MLOOP_2[64]={
+  0,4,5,5, 6,6,6,6, 7,7,7,7, 7,7,7,7,
+  8,8,8,8, 8,8,8,8, 8,8,8,8, 8,8,8,8,
+  9,9,9,9, 9,9,9,9, 9,9,9,9, 9,9,9,9,
+  9,9,9,9, 9,9,9,9, 9,9,9,9, 9,9,9,9,
+};
+
+static const unsigned char MLOOP_3[8]={0,1,2,2,3,3,3,3};
+
+void vorbis_lsp_to_curve(ogg_int32_t *curve,int *map,int n,int ln,
+			 ogg_int32_t *lsp,int m,
+			 ogg_int32_t amp,
+			 ogg_int32_t ampoffset,
+			 ogg_int32_t *icos){
+
+  /* 0 <= m < 256 */
+
+  /* set up for using all int later */
+  int i;
+  int ampoffseti=ampoffset*4096;
+  int ampi=amp;
+  ogg_int32_t *ilsp=(ogg_int32_t *)alloca(m*sizeof(*ilsp));
+  /* lsp is in 8.24, range 0 to PI; coslook wants it in .16 0 to 1*/
+  for(i=0;i<m;i++){
+#ifndef _LOW_ACCURACY_
+    ogg_int32_t val=MULT32(lsp[i],0x517cc2);
+#else
+    ogg_int32_t val=((lsp[i]>>10)*0x517d)>>14;
+#endif
+
+    /* safeguard against a malicious stream */
+    if(val<0 || (val>>COS_LOOKUP_I_SHIFT)>=COS_LOOKUP_I_SZ){
+      memset(curve,0,sizeof(*curve)*n);
+      return;
+    }
+
+    ilsp[i]=vorbis_coslook_i(val);
+  }
+
+  i=0;
+  while(i<n){
+    int j,k=map[i];
+    ogg_uint32_t pi=46341; /* 2**-.5 in 0.16 */
+    ogg_uint32_t qi=46341;
+    ogg_int32_t qexp=0,shift;
+    ogg_int32_t wi=icos[k];
+
+#ifdef _V_LSP_MATH_ASM
+    lsp_loop_asm(&qi,&pi,&qexp,ilsp,wi,m);
+
+    pi=((pi*pi)>>16);
+    qi=((qi*qi)>>16);
+    
+    if(m&1){
+      qexp= qexp*2-28*((m+1)>>1)+m;	     
+      pi*=(1<<14)-((wi*wi)>>14);
+      qi+=pi>>14;     
+    }else{
+      qexp= qexp*2-13*m;
+      
+      pi*=(1<<14)-wi;
+      qi*=(1<<14)+wi;
+      
+      qi=(qi+pi)>>14;
+    }
+    
+    if(qi&0xffff0000){ /* checks for 1.xxxxxxxxxxxxxxxx */
+      qi>>=1; qexp++; 
+    }else
+      lsp_norm_asm(&qi,&qexp);
+
+#else
+
+    qi*=labs(ilsp[0]-wi);
+    pi*=labs(ilsp[1]-wi);
+
+    for(j=3;j<m;j+=2){
+      if(!(shift=MLOOP_1[(pi|qi)>>25]))
+	if(!(shift=MLOOP_2[(pi|qi)>>19]))
+	  shift=MLOOP_3[(pi|qi)>>16];
+      qi=(qi>>shift)*labs(ilsp[j-1]-wi);
+      pi=(pi>>shift)*labs(ilsp[j]-wi);
+      qexp+=shift;
+    }
+    if(!(shift=MLOOP_1[(pi|qi)>>25]))
+      if(!(shift=MLOOP_2[(pi|qi)>>19]))
+	shift=MLOOP_3[(pi|qi)>>16];
+
+    /* pi,qi normalized collectively, both tracked using qexp */
+
+    if(m&1){
+      /* odd order filter; slightly assymetric */
+      /* the last coefficient */
+      qi=(qi>>shift)*labs(ilsp[j-1]-wi);
+      pi=(pi>>shift)<<14;
+      qexp+=shift;
+
+      if(!(shift=MLOOP_1[(pi|qi)>>25]))
+	if(!(shift=MLOOP_2[(pi|qi)>>19]))
+	  shift=MLOOP_3[(pi|qi)>>16];
+      
+      pi>>=shift;
+      qi>>=shift;
+      qexp+=shift-14*((m+1)>>1);
+
+      pi=((pi*pi)>>16);
+      qi=((qi*qi)>>16);
+      qexp=qexp*2+m;
+
+      pi*=(1<<14)-((wi*wi)>>14);
+      qi+=pi>>14;
+
+    }else{
+      /* even order filter; still symmetric */
+
+      /* p*=p(1-w), q*=q(1+w), let normalization drift because it isn't
+	 worth tracking step by step */
+      
+      pi>>=shift;
+      qi>>=shift;
+      qexp+=shift-7*m;
+
+      pi=((pi*pi)>>16);
+      qi=((qi*qi)>>16);
+      qexp=qexp*2+m;
+      
+      pi*=(1<<14)-wi;
+      qi*=(1<<14)+wi;
+      qi=(qi+pi)>>14;
+      
+    }
+    
+
+    /* we've let the normalization drift because it wasn't important;
+       however, for the lookup, things must be normalized again.  We
+       need at most one right shift or a number of left shifts */
+
+    if(qi&0xffff0000){ /* checks for 1.xxxxxxxxxxxxxxxx */
+      qi>>=1; qexp++; 
+    }else
+      while(qi && !(qi&0x8000)){ /* checks for 0.0xxxxxxxxxxxxxxx or less*/
+	qi<<=1; qexp--; 
+      }
+
+#endif
+
+    amp=vorbis_fromdBlook_i(ampi*                     /*  n.4         */
+			    vorbis_invsqlook_i(qi,qexp)- 
+			                              /*  m.8, m+n<=8 */
+			    ampoffseti);              /*  8.12[0]     */
+    
+#ifdef _LOW_ACCURACY_
+    amp>>=9;
+#endif
+    curve[i]= MULT31_SHIFT15(curve[i],amp);
+    while(map[++i]==k) curve[i]= MULT31_SHIFT15(curve[i],amp);
+  }
+}
+
+/*************** vorbis decode glue ************/
+
+static void floor0_free_info(vorbis_info_floor *i){
+  vorbis_info_floor0 *info=(vorbis_info_floor0 *)i;
+  if(info){
+    memset(info,0,sizeof(*info));
+    _ogg_free(info);
+  }
+}
+
+static void floor0_free_look(vorbis_look_floor *i){
+  vorbis_look_floor0 *look=(vorbis_look_floor0 *)i;
+  if(look){
+
+    if(look->linearmap)_ogg_free(look->linearmap);
+    if(look->lsp_look)_ogg_free(look->lsp_look);
+    memset(look,0,sizeof(*look));
+    _ogg_free(look);
+  }
+}
+
+static vorbis_info_floor *floor0_unpack (vorbis_info *vi,oggpack_buffer *opb){
+  codec_setup_info     *ci=(codec_setup_info *)vi->codec_setup;
+  int j;
+
+  vorbis_info_floor0 *info=(vorbis_info_floor0 *)_ogg_malloc(sizeof(*info));
+  info->order=oggpack_read(opb,8);
+  info->rate=oggpack_read(opb,16);
+  info->barkmap=oggpack_read(opb,16);
+  info->ampbits=oggpack_read(opb,6);
+  info->ampdB=oggpack_read(opb,8);
+  info->numbooks=oggpack_read(opb,4)+1;
+  
+  if(info->order<1)goto err_out;
+  if(info->rate<1)goto err_out;
+  if(info->barkmap<1)goto err_out;
+  if(info->numbooks<1)goto err_out;
+    
+  for(j=0;j<info->numbooks;j++){
+    info->books[j]=oggpack_read(opb,8);
+    if(info->books[j]<0 || info->books[j]>=ci->books)goto err_out;
+  }
+  return(info);
+
+ err_out:
+  floor0_free_info(info);
+  return(NULL);
+}
+
+/* initialize Bark scale and normalization lookups.  We could do this
+   with static tables, but Vorbis allows a number of possible
+   combinations, so it's best to do it computationally.
+
+   The below is authoritative in terms of defining scale mapping.
+   Note that the scale depends on the sampling rate as well as the
+   linear block and mapping sizes */
+
+static vorbis_look_floor *floor0_look (vorbis_dsp_state *vd,vorbis_info_mode *mi,
+                              vorbis_info_floor *i){
+  int j;
+  vorbis_info        *vi=vd->vi;
+  codec_setup_info   *ci=(codec_setup_info *)vi->codec_setup;
+  vorbis_info_floor0 *info=(vorbis_info_floor0 *)i;
+  vorbis_look_floor0 *look=(vorbis_look_floor0 *)_ogg_calloc(1,sizeof(*look));
+  look->m=info->order;
+  look->n=ci->blocksizes[mi->blockflag]/2;
+  look->ln=info->barkmap;
+  look->vi=info;
+
+  /* the mapping from a linear scale to a smaller bark scale is
+     straightforward.  We do *not* make sure that the linear mapping
+     does not skip bark-scale bins; the decoder simply skips them and
+     the encoder may do what it wishes in filling them.  They're
+     necessary in some mapping combinations to keep the scale spacing
+     accurate */
+  look->linearmap=(int *)_ogg_malloc((look->n+1)*sizeof(*look->linearmap));
+  for(j=0;j<look->n;j++){
+
+    int val=(look->ln*
+	     ((toBARK(info->rate/2*j/look->n)<<11)/toBARK(info->rate/2)))>>11;
+
+    if(val>=look->ln)val=look->ln-1; /* guard against the approximation */
+    look->linearmap[j]=val;
+  }
+  look->linearmap[j]=-1;
+
+  look->lsp_look=(ogg_int32_t *)_ogg_malloc(look->ln*sizeof(*look->lsp_look));
+  for(j=0;j<look->ln;j++)
+    look->lsp_look[j]=vorbis_coslook2_i(0x10000*j/look->ln);
+
+  return look;
+}
+
+static void *floor0_inverse1(vorbis_block *vb,vorbis_look_floor *i){
+  vorbis_look_floor0 *look=(vorbis_look_floor0 *)i;
+  vorbis_info_floor0 *info=look->vi;
+  int j,k;
+  
+  int ampraw=oggpack_read(&vb->opb,info->ampbits);
+  if(ampraw>0){ /* also handles the -1 out of data case */
+    long maxval=(1<<info->ampbits)-1;
+    int amp=((ampraw*info->ampdB)<<4)/maxval;
+    int booknum=oggpack_read(&vb->opb,_ilog(info->numbooks));
+    
+    if(booknum!=-1 && booknum<info->numbooks){ /* be paranoid */
+      codec_setup_info  *ci=(codec_setup_info *)vb->vd->vi->codec_setup;
+      codebook *b=ci->fullbooks+info->books[booknum];
+      ogg_int32_t last=0;
+      ogg_int32_t *lsp=(ogg_int32_t *)_vorbis_block_alloc(vb,sizeof(*lsp)*(look->m+1));
+            
+      for(j=0;j<look->m;j+=b->dim)
+	if(vorbis_book_decodev_set(b,lsp+j,&vb->opb,b->dim,-24)==-1)goto eop;
+      for(j=0;j<look->m;){
+	for(k=0;k<b->dim;k++,j++)lsp[j]+=last;
+	last=lsp[j-1];
+      }
+      
+      lsp[look->m]=amp;
+      return(lsp);
+    }
+  }
+ eop:
+  return(NULL);
+}
+
+static int floor0_inverse2(vorbis_block *vb,vorbis_look_floor *i,
+			   void *memo,ogg_int32_t *out){
+  vorbis_look_floor0 *look=(vorbis_look_floor0 *)i;
+  vorbis_info_floor0 *info=look->vi;
+  
+  if(memo){
+    ogg_int32_t *lsp=(ogg_int32_t *)memo;
+    ogg_int32_t amp=lsp[look->m];
+
+    /* take the coefficients back to a spectral envelope curve */
+    vorbis_lsp_to_curve(out,look->linearmap,look->n,look->ln,
+			lsp,look->m,amp,info->ampdB,look->lsp_look);
+    return(1);
+  }
+  memset(out,0,sizeof(*out)*look->n);
+  return(0);
+}
+
+/* export hooks */
+vorbis_func_floor floor0_exportbundle={
+  &floor0_unpack,&floor0_look,&floor0_free_info,
+  &floor0_free_look,&floor0_inverse1,&floor0_inverse2
+};
+
+