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Diffstat (limited to 'media/libvorbis/lib/vorbis_codebook.c')
-rw-r--r--media/libvorbis/lib/vorbis_codebook.c490
1 files changed, 490 insertions, 0 deletions
diff --git a/media/libvorbis/lib/vorbis_codebook.c b/media/libvorbis/lib/vorbis_codebook.c
new file mode 100644
index 0000000000..72f8a17a35
--- /dev/null
+++ b/media/libvorbis/lib/vorbis_codebook.c
@@ -0,0 +1,490 @@
+/********************************************************************
+ * *
+ * THIS FILE IS PART OF THE OggVorbis SOFTWARE 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 SOURCE CODE IS (C) COPYRIGHT 1994-2015 *
+ * by the Xiph.Org Foundation http://www.xiph.org/ *
+ * *
+ ********************************************************************
+
+ function: basic codebook pack/unpack/code/decode operations
+ last mod: $Id: codebook.c 19457 2015-03-03 00:15:29Z giles $
+
+ ********************************************************************/
+
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+#include <ogg/ogg.h>
+#include "vorbis/codec.h"
+#include "codebook.h"
+#include "scales.h"
+#include "misc.h"
+#include "os.h"
+
+/* packs the given codebook into the bitstream **************************/
+
+int vorbis_staticbook_pack(const static_codebook *c,oggpack_buffer *opb){
+ long i,j;
+ int ordered=0;
+
+ /* first the basic parameters */
+ oggpack_write(opb,0x564342,24);
+ oggpack_write(opb,c->dim,16);
+ oggpack_write(opb,c->entries,24);
+
+ /* pack the codewords. There are two packings; length ordered and
+ length random. Decide between the two now. */
+
+ for(i=1;i<c->entries;i++)
+ if(c->lengthlist[i-1]==0 || c->lengthlist[i]<c->lengthlist[i-1])break;
+ if(i==c->entries)ordered=1;
+
+ if(ordered){
+ /* length ordered. We only need to say how many codewords of
+ each length. The actual codewords are generated
+ deterministically */
+
+ long count=0;
+ oggpack_write(opb,1,1); /* ordered */
+ oggpack_write(opb,c->lengthlist[0]-1,5); /* 1 to 32 */
+
+ for(i=1;i<c->entries;i++){
+ char this=c->lengthlist[i];
+ char last=c->lengthlist[i-1];
+ if(this>last){
+ for(j=last;j<this;j++){
+ oggpack_write(opb,i-count,ov_ilog(c->entries-count));
+ count=i;
+ }
+ }
+ }
+ oggpack_write(opb,i-count,ov_ilog(c->entries-count));
+
+ }else{
+ /* length random. Again, we don't code the codeword itself, just
+ the length. This time, though, we have to encode each length */
+ oggpack_write(opb,0,1); /* unordered */
+
+ /* algortihmic mapping has use for 'unused entries', which we tag
+ here. The algorithmic mapping happens as usual, but the unused
+ entry has no codeword. */
+ for(i=0;i<c->entries;i++)
+ if(c->lengthlist[i]==0)break;
+
+ if(i==c->entries){
+ oggpack_write(opb,0,1); /* no unused entries */
+ for(i=0;i<c->entries;i++)
+ oggpack_write(opb,c->lengthlist[i]-1,5);
+ }else{
+ oggpack_write(opb,1,1); /* we have unused entries; thus we tag */
+ for(i=0;i<c->entries;i++){
+ if(c->lengthlist[i]==0){
+ oggpack_write(opb,0,1);
+ }else{
+ oggpack_write(opb,1,1);
+ oggpack_write(opb,c->lengthlist[i]-1,5);
+ }
+ }
+ }
+ }
+
+ /* is the entry number the desired return value, or do we have a
+ mapping? If we have a mapping, what type? */
+ oggpack_write(opb,c->maptype,4);
+ switch(c->maptype){
+ case 0:
+ /* no mapping */
+ break;
+ case 1:case 2:
+ /* implicitly populated value mapping */
+ /* explicitly populated value mapping */
+
+ if(!c->quantlist){
+ /* no quantlist? error */
+ return(-1);
+ }
+
+ /* values that define the dequantization */
+ oggpack_write(opb,c->q_min,32);
+ oggpack_write(opb,c->q_delta,32);
+ oggpack_write(opb,c->q_quant-1,4);
+ oggpack_write(opb,c->q_sequencep,1);
+
+ {
+ int quantvals;
+ switch(c->maptype){
+ case 1:
+ /* a single column of (c->entries/c->dim) quantized values for
+ building a full value list algorithmically (square lattice) */
+ quantvals=_book_maptype1_quantvals(c);
+ break;
+ case 2:
+ /* every value (c->entries*c->dim total) specified explicitly */
+ quantvals=c->entries*c->dim;
+ break;
+ default: /* NOT_REACHABLE */
+ quantvals=-1;
+ }
+
+ /* quantized values */
+ for(i=0;i<quantvals;i++)
+ oggpack_write(opb,labs(c->quantlist[i]),c->q_quant);
+
+ }
+ break;
+ default:
+ /* error case; we don't have any other map types now */
+ return(-1);
+ }
+
+ return(0);
+}
+
+/* unpacks a codebook from the packet buffer into the codebook struct,
+ readies the codebook auxiliary structures for decode *************/
+static_codebook *vorbis_staticbook_unpack(oggpack_buffer *opb){
+ long i,j;
+ static_codebook *s=_ogg_calloc(1,sizeof(*s));
+ s->allocedp=1;
+
+ /* make sure alignment is correct */
+ if(oggpack_read(opb,24)!=0x564342)goto _eofout;
+
+ /* first the basic parameters */
+ s->dim=oggpack_read(opb,16);
+ s->entries=oggpack_read(opb,24);
+ if(s->entries==-1)goto _eofout;
+
+ if(ov_ilog(s->dim)+ov_ilog(s->entries)>24)goto _eofout;
+
+ /* codeword ordering.... length ordered or unordered? */
+ switch((int)oggpack_read(opb,1)){
+ case 0:{
+ long unused;
+ /* allocated but unused entries? */
+ unused=oggpack_read(opb,1);
+ if((s->entries*(unused?1:5)+7)>>3>opb->storage-oggpack_bytes(opb))
+ goto _eofout;
+ /* unordered */
+ s->lengthlist=_ogg_malloc(sizeof(*s->lengthlist)*s->entries);
+
+ /* allocated but unused entries? */
+ if(unused){
+ /* yes, unused entries */
+
+ for(i=0;i<s->entries;i++){
+ if(oggpack_read(opb,1)){
+ long num=oggpack_read(opb,5);
+ if(num==-1)goto _eofout;
+ s->lengthlist[i]=num+1;
+ }else
+ s->lengthlist[i]=0;
+ }
+ }else{
+ /* all entries used; no tagging */
+ for(i=0;i<s->entries;i++){
+ long num=oggpack_read(opb,5);
+ if(num==-1)goto _eofout;
+ s->lengthlist[i]=num+1;
+ }
+ }
+
+ break;
+ }
+ case 1:
+ /* ordered */
+ {
+ long length=oggpack_read(opb,5)+1;
+ if(length==0)goto _eofout;
+ s->lengthlist=_ogg_malloc(sizeof(*s->lengthlist)*s->entries);
+
+ for(i=0;i<s->entries;){
+ long num=oggpack_read(opb,ov_ilog(s->entries-i));
+ if(num==-1)goto _eofout;
+ if(length>32 || num>s->entries-i ||
+ (num>0 && (num-1)>>(length-1)>1)){
+ goto _errout;
+ }
+ if(length>32)goto _errout;
+ for(j=0;j<num;j++,i++)
+ s->lengthlist[i]=length;
+ length++;
+ }
+ }
+ break;
+ default:
+ /* EOF */
+ goto _eofout;
+ }
+
+ /* Do we have a mapping to unpack? */
+ switch((s->maptype=oggpack_read(opb,4))){
+ case 0:
+ /* no mapping */
+ break;
+ case 1: case 2:
+ /* implicitly populated value mapping */
+ /* explicitly populated value mapping */
+
+ s->q_min=oggpack_read(opb,32);
+ s->q_delta=oggpack_read(opb,32);
+ s->q_quant=oggpack_read(opb,4)+1;
+ s->q_sequencep=oggpack_read(opb,1);
+ if(s->q_sequencep==-1)goto _eofout;
+
+ {
+ int quantvals=0;
+ switch(s->maptype){
+ case 1:
+ quantvals=(s->dim==0?0:_book_maptype1_quantvals(s));
+ break;
+ case 2:
+ quantvals=s->entries*s->dim;
+ break;
+ }
+
+ /* quantized values */
+ if(((quantvals*s->q_quant+7)>>3)>opb->storage-oggpack_bytes(opb))
+ goto _eofout;
+ s->quantlist=_ogg_malloc(sizeof(*s->quantlist)*quantvals);
+ for(i=0;i<quantvals;i++)
+ s->quantlist[i]=oggpack_read(opb,s->q_quant);
+
+ if(quantvals&&s->quantlist[quantvals-1]==-1)goto _eofout;
+ }
+ break;
+ default:
+ goto _errout;
+ }
+
+ /* all set */
+ return(s);
+
+ _errout:
+ _eofout:
+ vorbis_staticbook_destroy(s);
+ return(NULL);
+}
+
+/* returns the number of bits ************************************************/
+int vorbis_book_encode(codebook *book, int a, oggpack_buffer *b){
+ if(a<0 || a>=book->c->entries)return(0);
+ oggpack_write(b,book->codelist[a],book->c->lengthlist[a]);
+ return(book->c->lengthlist[a]);
+}
+
+/* the 'eliminate the decode tree' optimization actually requires the
+ codewords to be MSb first, not LSb. This is an annoying inelegancy
+ (and one of the first places where carefully thought out design
+ turned out to be wrong; Vorbis II and future Ogg codecs should go
+ to an MSb bitpacker), but not actually the huge hit it appears to
+ be. The first-stage decode table catches most words so that
+ bitreverse is not in the main execution path. */
+
+static ogg_uint32_t bitreverse(ogg_uint32_t x){
+ x= ((x>>16)&0x0000ffff) | ((x<<16)&0xffff0000);
+ x= ((x>> 8)&0x00ff00ff) | ((x<< 8)&0xff00ff00);
+ x= ((x>> 4)&0x0f0f0f0f) | ((x<< 4)&0xf0f0f0f0);
+ x= ((x>> 2)&0x33333333) | ((x<< 2)&0xcccccccc);
+ return((x>> 1)&0x55555555) | ((x<< 1)&0xaaaaaaaa);
+}
+
+STIN long decode_packed_entry_number(codebook *book, oggpack_buffer *b){
+ int read=book->dec_maxlength;
+ long lo,hi;
+ long lok = oggpack_look(b,book->dec_firsttablen);
+
+ if (lok >= 0) {
+ long entry = book->dec_firsttable[lok];
+ if(entry&0x80000000UL){
+ lo=(entry>>15)&0x7fff;
+ hi=book->used_entries-(entry&0x7fff);
+ }else{
+ oggpack_adv(b, book->dec_codelengths[entry-1]);
+ return(entry-1);
+ }
+ }else{
+ lo=0;
+ hi=book->used_entries;
+ }
+
+ /* Single entry codebooks use a firsttablen of 1 and a
+ dec_maxlength of 1. If a single-entry codebook gets here (due to
+ failure to read one bit above), the next look attempt will also
+ fail and we'll correctly kick out instead of trying to walk the
+ underformed tree */
+
+ lok = oggpack_look(b, read);
+
+ while(lok<0 && read>1)
+ lok = oggpack_look(b, --read);
+ if(lok<0)return -1;
+
+ /* bisect search for the codeword in the ordered list */
+ {
+ ogg_uint32_t testword=bitreverse((ogg_uint32_t)lok);
+
+ while(hi-lo>1){
+ long p=(hi-lo)>>1;
+ long test=book->codelist[lo+p]>testword;
+ lo+=p&(test-1);
+ hi-=p&(-test);
+ }
+
+ if(book->dec_codelengths[lo]<=read){
+ oggpack_adv(b, book->dec_codelengths[lo]);
+ return(lo);
+ }
+ }
+
+ oggpack_adv(b, read);
+
+ return(-1);
+}
+
+/* Decode side is specced and easier, because we don't need to find
+ matches using different criteria; we simply read and map. There are
+ two things we need to do 'depending':
+
+ We may need to support interleave. We don't really, but it's
+ convenient to do it here rather than rebuild the vector later.
+
+ Cascades may be additive or multiplicitive; this is not inherent in
+ the codebook, but set in the code using the codebook. Like
+ interleaving, it's easiest to do it here.
+ addmul==0 -> declarative (set the value)
+ addmul==1 -> additive
+ addmul==2 -> multiplicitive */
+
+/* returns the [original, not compacted] entry number or -1 on eof *********/
+long vorbis_book_decode(codebook *book, oggpack_buffer *b){
+ if(book->used_entries>0){
+ long packed_entry=decode_packed_entry_number(book,b);
+ if(packed_entry>=0)
+ return(book->dec_index[packed_entry]);
+ }
+
+ /* if there's no dec_index, the codebook unpacking isn't collapsed */
+ return(-1);
+}
+
+/* returns 0 on OK or -1 on eof *************************************/
+/* decode vector / dim granularity gaurding is done in the upper layer */
+long vorbis_book_decodevs_add(codebook *book,float *a,oggpack_buffer *b,int n){
+ if(book->used_entries>0){
+ int step=n/book->dim;
+ long *entry = alloca(sizeof(*entry)*step);
+ float **t = alloca(sizeof(*t)*step);
+ int i,j,o;
+
+ for (i = 0; i < step; i++) {
+ entry[i]=decode_packed_entry_number(book,b);
+ if(entry[i]==-1)return(-1);
+ t[i] = book->valuelist+entry[i]*book->dim;
+ }
+ for(i=0,o=0;i<book->dim;i++,o+=step)
+ for (j=0;j<step;j++)
+ a[o+j]+=t[j][i];
+ }
+ return(0);
+}
+
+/* decode vector / dim granularity gaurding is done in the upper layer */
+long vorbis_book_decodev_add(codebook *book,float *a,oggpack_buffer *b,int n){
+ if(book->used_entries>0){
+ int i,j,entry;
+ float *t;
+
+ if(book->dim>8){
+ for(i=0;i<n;){
+ entry = decode_packed_entry_number(book,b);
+ if(entry==-1)return(-1);
+ t = book->valuelist+entry*book->dim;
+ for (j=0;j<book->dim;)
+ a[i++]+=t[j++];
+ }
+ }else{
+ for(i=0;i<n;){
+ entry = decode_packed_entry_number(book,b);
+ if(entry==-1)return(-1);
+ t = book->valuelist+entry*book->dim;
+ j=0;
+ switch((int)book->dim){
+ case 8:
+ a[i++]+=t[j++];
+ case 7:
+ a[i++]+=t[j++];
+ case 6:
+ a[i++]+=t[j++];
+ case 5:
+ a[i++]+=t[j++];
+ case 4:
+ a[i++]+=t[j++];
+ case 3:
+ a[i++]+=t[j++];
+ case 2:
+ a[i++]+=t[j++];
+ case 1:
+ a[i++]+=t[j++];
+ case 0:
+ break;
+ }
+ }
+ }
+ }
+ return(0);
+}
+
+/* unlike the others, we guard against n not being an integer number
+ of <dim> internally rather than in the upper layer (called only by
+ floor0) */
+long vorbis_book_decodev_set(codebook *book,float *a,oggpack_buffer *b,int n){
+ if(book->used_entries>0){
+ int i,j,entry;
+ float *t;
+
+ for(i=0;i<n;){
+ entry = decode_packed_entry_number(book,b);
+ if(entry==-1)return(-1);
+ t = book->valuelist+entry*book->dim;
+ for (j=0;i<n && j<book->dim;){
+ a[i++]=t[j++];
+ }
+ }
+ }else{
+ int i;
+
+ for(i=0;i<n;){
+ a[i++]=0.f;
+ }
+ }
+ return(0);
+}
+
+long vorbis_book_decodevv_add(codebook *book,float **a,long offset,int ch,
+ oggpack_buffer *b,int n){
+
+ long i,j,entry;
+ int chptr=0;
+ if(book->used_entries>0){
+ for(i=offset/ch;i<(offset+n)/ch;){
+ entry = decode_packed_entry_number(book,b);
+ if(entry==-1)return(-1);
+ {
+ const float *t = book->valuelist+entry*book->dim;
+ for (j=0;j<book->dim;j++){
+ a[chptr++][i]+=t[j];
+ if(chptr==ch){
+ chptr=0;
+ i++;
+ }
+ }
+ }
+ }
+ }
+ return(0);
+}
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