diff -r e353ca78d28b -r f7e49eff3708 misc/libtremor/block.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/misc/libtremor/block.c	Sun Apr 24 22:57:57 2011 +0200
@@ -0,0 +1,453 @@
+/********************************************************************
+ *                                                                  *
+ * 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: PCM data vector blocking, windowing and dis/reassembly
+
+ ********************************************************************/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "ogg.h"
+#include "ivorbiscodec.h"
+#include "codec_internal.h"
+
+#include "window.h"
+#include "registry.h"
+#include "misc.h"
+
+static int ilog(unsigned int v){
+  int ret=0;
+  if(v)--v;
+  while(v){
+    ret++;
+    v>>=1;
+  }
+  return(ret);
+}
+
+/* pcm accumulator examples (not exhaustive):
+
+ <-------------- lW ---------------->
+                   <--------------- W ---------------->
+:            .....|.....       _______________         |
+:        .'''     |     '''_---      |       |\        |
+:.....'''         |_____--- '''......|       | \_______|
+:.................|__________________|_______|__|______|
+                  |<------ Sl ------>|      > Sr <     |endW
+                  |beginSl           |endSl  |  |endSr
+                  |beginW            |endlW  |beginSr
+
+
+                      |< lW >|
+                   <--------------- W ---------------->
+                  |   |  ..  ______________            |
+                  |   | '  `/        |     ---_        |
+                  |___.'___/`.       |         ---_____|
+                  |_______|__|_______|_________________|
+                  |      >|Sl|<      |<------ Sr ----->|endW
+                  |       |  |endSl  |beginSr          |endSr
+                  |beginW |  |endlW
+                  mult[0] |beginSl                     mult[n]
+
+ <-------------- lW ----------------->
+                          |<--W-->|
+:            ..............  ___  |   |
+:        .'''             |`/   \ |   |
+:.....'''                 |/`....\|...|
+:.........................|___|___|___|
+                          |Sl |Sr |endW
+                          |   |   |endSr
+                          |   |beginSr
+                          |   |endSl
+			  |beginSl
+			  |beginW
+*/
+
+/* block abstraction setup *********************************************/
+
+#ifndef WORD_ALIGN
+#define WORD_ALIGN 8
+#endif
+
+int vorbis_block_init(vorbis_dsp_state *v, vorbis_block *vb){
+  memset(vb,0,sizeof(*vb));
+  vb->vd=v;
+  vb->localalloc=0;
+  vb->localstore=NULL;
+
+  return(0);
+}
+
+void *_vorbis_block_alloc(vorbis_block *vb,long bytes){
+  bytes=(bytes+(WORD_ALIGN-1)) & ~(WORD_ALIGN-1);
+  if(bytes+vb->localtop>vb->localalloc){
+    /* can't just _ogg_realloc... there are outstanding pointers */
+    if(vb->localstore){
+      struct alloc_chain *link=(struct alloc_chain *)_ogg_malloc(sizeof(*link));
+      vb->totaluse+=vb->localtop;
+      link->next=vb->reap;
+      link->ptr=vb->localstore;
+      vb->reap=link;
+    }
+    /* highly conservative */
+    vb->localalloc=bytes;
+    vb->localstore=_ogg_malloc(vb->localalloc);
+    vb->localtop=0;
+  }
+  {
+    void *ret=(void *)(((char *)vb->localstore)+vb->localtop);
+    vb->localtop+=bytes;
+    return ret;
+  }
+}
+
+/* reap the chain, pull the ripcord */
+void _vorbis_block_ripcord(vorbis_block *vb){
+  /* reap the chain */
+  struct alloc_chain *reap=vb->reap;
+  while(reap){
+    struct alloc_chain *next=reap->next;
+    _ogg_free(reap->ptr);
+    memset(reap,0,sizeof(*reap));
+    _ogg_free(reap);
+    reap=next;
+  }
+  /* consolidate storage */
+  if(vb->totaluse){
+    vb->localstore=_ogg_realloc(vb->localstore,vb->totaluse+vb->localalloc);
+    vb->localalloc+=vb->totaluse;
+    vb->totaluse=0;
+  }
+
+  /* pull the ripcord */
+  vb->localtop=0;
+  vb->reap=NULL;
+}
+
+int vorbis_block_clear(vorbis_block *vb){
+  _vorbis_block_ripcord(vb);
+  if(vb->localstore)_ogg_free(vb->localstore);
+
+  memset(vb,0,sizeof(*vb));
+  return(0);
+}
+
+static int _vds_init(vorbis_dsp_state *v,vorbis_info *vi){
+  int i;
+  codec_setup_info *ci=(codec_setup_info *)vi->codec_setup;
+  private_state *b=NULL;
+
+  memset(v,0,sizeof(*v));
+  b=(private_state *)(v->backend_state=_ogg_calloc(1,sizeof(*b)));
+
+  v->vi=vi;
+  b->modebits=ilog(ci->modes);
+
+  /* Vorbis I uses only window type 0 */
+  b->window[0]=_vorbis_window(0,ci->blocksizes[0]/2);
+  b->window[1]=_vorbis_window(0,ci->blocksizes[1]/2);
+
+  /* finish the codebooks */
+  if(!ci->fullbooks){
+    ci->fullbooks=(codebook *)_ogg_calloc(ci->books,sizeof(*ci->fullbooks));
+    for(i=0;i<ci->books;i++){
+      vorbis_book_init_decode(ci->fullbooks+i,ci->book_param[i]);
+      /* decode codebooks are now standalone after init */
+      vorbis_staticbook_destroy(ci->book_param[i]);
+      ci->book_param[i]=NULL;
+    }
+  }
+
+  v->pcm_storage=ci->blocksizes[1];
+  v->pcm=(ogg_int32_t **)_ogg_malloc(vi->channels*sizeof(*v->pcm));
+  v->pcmret=(ogg_int32_t **)_ogg_malloc(vi->channels*sizeof(*v->pcmret));
+  for(i=0;i<vi->channels;i++)
+    v->pcm[i]=(ogg_int32_t *)_ogg_calloc(v->pcm_storage,sizeof(*v->pcm[i]));
+
+  /* all 1 (large block) or 0 (small block) */
+  /* explicitly set for the sake of clarity */
+  v->lW=0; /* previous window size */
+  v->W=0;  /* current window size */
+
+  /* initialize all the mapping/backend lookups */
+  b->mode=(vorbis_look_mapping **)_ogg_calloc(ci->modes,sizeof(*b->mode));
+  for(i=0;i<ci->modes;i++){
+    int mapnum=ci->mode_param[i]->mapping;
+    int maptype=ci->map_type[mapnum];
+    b->mode[i]=_mapping_P[maptype]->look(v,ci->mode_param[i],
+					 ci->map_param[mapnum]);
+  }
+  return(0);
+}
+
+int vorbis_synthesis_restart(vorbis_dsp_state *v){
+  vorbis_info *vi=v->vi;
+  codec_setup_info *ci;
+
+  if(!v->backend_state)return -1;
+  if(!vi)return -1;
+  ci=vi->codec_setup;
+  if(!ci)return -1;
+
+  v->centerW=ci->blocksizes[1]/2;
+  v->pcm_current=v->centerW;
+
+  v->pcm_returned=-1;
+  v->granulepos=-1;
+  v->sequence=-1;
+  ((private_state *)(v->backend_state))->sample_count=-1;
+
+  return(0);
+}
+
+int vorbis_synthesis_init(vorbis_dsp_state *v,vorbis_info *vi){
+  _vds_init(v,vi);
+  vorbis_synthesis_restart(v);
+
+  return(0);
+}
+
+void vorbis_dsp_clear(vorbis_dsp_state *v){
+  int i;
+  if(v){
+    vorbis_info *vi=v->vi;
+    codec_setup_info *ci=(codec_setup_info *)(vi?vi->codec_setup:NULL);
+    private_state *b=(private_state *)v->backend_state;
+
+    if(v->pcm){
+      for(i=0;i<vi->channels;i++)
+	if(v->pcm[i])_ogg_free(v->pcm[i]);
+      _ogg_free(v->pcm);
+      if(v->pcmret)_ogg_free(v->pcmret);
+    }
+
+    /* free mode lookups; these are actually vorbis_look_mapping structs */
+    if(ci){
+      for(i=0;i<ci->modes;i++){
+	int mapnum=ci->mode_param[i]->mapping;
+	int maptype=ci->map_type[mapnum];
+	if(b && b->mode)_mapping_P[maptype]->free_look(b->mode[i]);
+      }
+    }
+
+    if(b){
+      if(b->mode)_ogg_free(b->mode);
+      _ogg_free(b);
+    }
+
+    memset(v,0,sizeof(*v));
+  }
+}
+
+/* Unlike in analysis, the window is only partially applied for each
+   block.  The time domain envelope is not yet handled at the point of
+   calling (as it relies on the previous block). */
+
+int vorbis_synthesis_blockin(vorbis_dsp_state *v,vorbis_block *vb){
+  vorbis_info *vi=v->vi;
+  codec_setup_info *ci=(codec_setup_info *)vi->codec_setup;
+  private_state *b=v->backend_state;
+  int i,j;
+
+  if(v->pcm_current>v->pcm_returned  && v->pcm_returned!=-1)return(OV_EINVAL);
+
+  v->lW=v->W;
+  v->W=vb->W;
+  v->nW=-1;
+
+  if((v->sequence==-1)||
+     (v->sequence+1 != vb->sequence)){
+    v->granulepos=-1; /* out of sequence; lose count */
+    b->sample_count=-1;
+  }
+
+  v->sequence=vb->sequence;
+
+  if(vb->pcm){  /* no pcm to process if vorbis_synthesis_trackonly
+                   was called on block */
+    int n=ci->blocksizes[v->W]/2;
+    int n0=ci->blocksizes[0]/2;
+    int n1=ci->blocksizes[1]/2;
+
+    int thisCenter;
+    int prevCenter;
+
+    if(v->centerW){
+      thisCenter=n1;
+      prevCenter=0;
+    }else{
+      thisCenter=0;
+      prevCenter=n1;
+    }
+
+    /* v->pcm is now used like a two-stage double buffer.  We don't want
+       to have to constantly shift *or* adjust memory usage.  Don't
+       accept a new block until the old is shifted out */
+
+    /* overlap/add PCM */
+
+    for(j=0;j<vi->channels;j++){
+      /* the overlap/add section */
+      if(v->lW){
+	if(v->W){
+	  /* large/large */
+	  ogg_int32_t *pcm=v->pcm[j]+prevCenter;
+	  ogg_int32_t *p=vb->pcm[j];
+	  for(i=0;i<n1;i++)
+	    pcm[i]+=p[i];
+	}else{
+	  /* large/small */
+	  ogg_int32_t *pcm=v->pcm[j]+prevCenter+n1/2-n0/2;
+	  ogg_int32_t *p=vb->pcm[j];
+	  for(i=0;i<n0;i++)
+	    pcm[i]+=p[i];
+	}
+      }else{
+	if(v->W){
+	  /* small/large */
+	  ogg_int32_t *pcm=v->pcm[j]+prevCenter;
+	  ogg_int32_t *p=vb->pcm[j]+n1/2-n0/2;
+	  for(i=0;i<n0;i++)
+	    pcm[i]+=p[i];
+	  for(;i<n1/2+n0/2;i++)
+	    pcm[i]=p[i];
+	}else{
+	  /* small/small */
+	  ogg_int32_t *pcm=v->pcm[j]+prevCenter;
+	  ogg_int32_t *p=vb->pcm[j];
+	  for(i=0;i<n0;i++)
+	    pcm[i]+=p[i];
+	}
+      }
+
+      /* the copy section */
+      {
+	ogg_int32_t *pcm=v->pcm[j]+thisCenter;
+	ogg_int32_t *p=vb->pcm[j]+n;
+	for(i=0;i<n;i++)
+	  pcm[i]=p[i];
+      }
+    }
+
+    if(v->centerW)
+      v->centerW=0;
+    else
+      v->centerW=n1;
+
+    /* deal with initial packet state; we do this using the explicit
+       pcm_returned==-1 flag otherwise we're sensitive to first block
+       being short or long */
+
+    if(v->pcm_returned==-1){
+      v->pcm_returned=thisCenter;
+      v->pcm_current=thisCenter;
+    }else{
+      v->pcm_returned=prevCenter;
+      v->pcm_current=prevCenter+
+	ci->blocksizes[v->lW]/4+
+	ci->blocksizes[v->W]/4;
+    }
+
+  }
+
+  /* track the frame number... This is for convenience, but also
+     making sure our last packet doesn't end with added padding.  If
+     the last packet is partial, the number of samples we'll have to
+     return will be past the vb->granulepos.
+     
+     This is not foolproof!  It will be confused if we begin
+     decoding at the last page after a seek or hole.  In that case,
+     we don't have a starting point to judge where the last frame
+     is.  For this reason, vorbisfile will always try to make sure
+     it reads the last two marked pages in proper sequence */
+
+  if(b->sample_count==-1){
+    b->sample_count=0;
+  }else{
+    b->sample_count+=ci->blocksizes[v->lW]/4+ci->blocksizes[v->W]/4;
+  }
+
+  if(v->granulepos==-1){
+    if(vb->granulepos!=-1){ /* only set if we have a position to set to */
+
+      v->granulepos=vb->granulepos;
+
+      /* is this a short page? */
+      if(b->sample_count>v->granulepos){
+	/* corner case; if this is both the first and last audio page,
+	   then spec says the end is cut, not beginning */
+	if(vb->eofflag){
+	  /* trim the end */
+	  /* no preceeding granulepos; assume we started at zero (we'd
+	     have to in a short single-page stream) */
+	  /* granulepos could be -1 due to a seek, but that would result
+	     in a long coun`t, not short count */
+
+	  v->pcm_current-=(b->sample_count-v->granulepos);
+	}else{
+	  /* trim the beginning */
+	  v->pcm_returned+=(b->sample_count-v->granulepos);
+	  if(v->pcm_returned>v->pcm_current)
+	    v->pcm_returned=v->pcm_current;
+	}
+
+      }
+
+    }
+  }else{
+    v->granulepos+=ci->blocksizes[v->lW]/4+ci->blocksizes[v->W]/4;
+    if(vb->granulepos!=-1 && v->granulepos!=vb->granulepos){
+      
+      if(v->granulepos>vb->granulepos){
+	long extra=v->granulepos-vb->granulepos;
+	
+	if(extra)
+	  if(vb->eofflag){
+	    /* partial last frame.  Strip the extra samples off */
+	    v->pcm_current-=extra;
+	  } /* else {Shouldn't happen *unless* the bitstream is out of
+	       spec.  Either way, believe the bitstream } */
+      } /* else {Shouldn't happen *unless* the bitstream is out of
+	   spec.  Either way, believe the bitstream } */
+      v->granulepos=vb->granulepos;
+    }
+  }
+
+  /* Update, cleanup */
+
+  if(vb->eofflag)v->eofflag=1;
+  return(0);
+}
+
+/* pcm==NULL indicates we just want the pending samples, no more */
+int vorbis_synthesis_pcmout(vorbis_dsp_state *v,ogg_int32_t ***pcm){
+  vorbis_info *vi=v->vi;
+  if(v->pcm_returned>-1 && v->pcm_returned<v->pcm_current){
+    if(pcm){
+      int i;
+      for(i=0;i<vi->channels;i++)
+	v->pcmret[i]=v->pcm[i]+v->pcm_returned;
+      *pcm=v->pcmret;
+    }
+    return(v->pcm_current-v->pcm_returned);
+  }
+  return(0);
+}
+
+int vorbis_synthesis_read(vorbis_dsp_state *v,int bytes){
+  if(bytes && v->pcm_returned+bytes>v->pcm_current)return(OV_EINVAL);
+  v->pcm_returned+=bytes;
+  return(0);
+}
+