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Original Commit: r4 | ods15 | 2006-09-16 15:36:03 +0300 (Sat, 16 Sep 2006) | 3 lines

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codebook header syntax
small simplification for encode_init()

Originally committed as revision 6415 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Oded Shimon 2006-10-02 05:55:16 +00:00
parent 3a5fdf92f5
commit 0688b89c6d
1 changed files with 97 additions and 5 deletions
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102
libavcodec/vorbis_enc.c
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@ -27,15 +27,109 @@
#undef NDEBUG
#include <assert.h>
#define ALT_BITSTREAM_READER_LE
#include "bitstream.h"
#define VORBIS_FRAME_SIZE 64
#define BUFFER_SIZE (1024*64)
typedef struct {
uint8_t buffer[BUFFER_SIZE];
int buffer_index;
int len;
uint32_t codeword;
} entry_t;
typedef struct {
int nentries;
entry_t * entries;
int ndimentions;
float min;
float delta;
int seq_p;
int lookup;
//float * dimentions;
int * quantlist;
} codebook_t;
typedef struct {
int ncodebooks;
codebook_t * codebooks;
} venc_context_t;
static inline int ilog(int a) {
int i;
for (i = 0; (a >> i) > 0; i++);
return i;
}
static void put_codebook_header(PutBitContext * pb, codebook_t * cb) {
int i;
int ordered = 0;
put_bits(pb, 24, 0x564342); //magic
put_bits(pb, 16, cb->ndimentions);
put_bits(pb, 24, cb->nentries);
for (i = 1; i < cb->nentries; i++) if (cb->entries[i].len < cb->entries[i-1].len) break;
if (i == cb->entires) ordered = 1;
put_bits(pb, 1, ordered);
if (ordered) {
int len = cb->entries[0].len;
put_bits(pb, 5, len);
i = 0;
while (i < cb->nentries) {
for (j = 0; j+i < cb->nentries; j++) if (cb->entries[j+i].len != len) break;
put_bits(pb, 5, j);
i += j;
len++;
}
} else {
int sparse = 0;
for (i = 0; i < cb->nentries; i++) if (!cb->entries[i].len) break;
if (i != cb->entires) sparse = 1;
put_bits(pb, 1, sparse);
for (i = 0; i < cb->nentries; i++) {
if (sparse) put_bits(pb, 1, !!cb->entries[i].len);
if (cb->entries[i].len) put_bits(pb, 5, cb->entries[i].len);
}
}
put_bits(pb, 4, cb->lookup);
if (cb->lookup) {
int tmp, bits = ilog(cb->quantlist[0]);
if (cb->lookup == 1) {
for (tmp = 0; ; tmp++) {
int n = 1;
for (i = 0; i < cb->ndimentions; i++) n *= tmp;
if (n > cb->nentries) break;
}
tmp--;
} else tmp = cb->ndimentions * cb->nentries;
for (i = 1; i < tmp; i++) bits = FFMIN(bits, ilog(cb->quantlist[i]));
put_float(bc, cb->min);
put_float(bc, cb->delta);
put_bits(bc, 4, bits - 1);
put_bits(bc, 1, seq_p);
for (i = 0; i < tmp; i++) put_bits(bc, bits, cb->quantlist[i])
}
}
static void put_main_header(PutBitContext * pb, venc_context_t * venc) {
int i;
put_bits(pb, 8, 5); //magic
for (i = 0; "vorbis"[i]; i++) put_bits(pb, 8, "vorbis"[i]);
put_bits(pb, 8, venc->ncodebooks - 1);
for (i = 0; i < venc->ncodebooks; i++) put_codebook_header(pb, venc->codebooks[0]);
}
static int vorbis_encode_init(AVCodecContext * avccontext)
{
venc_context_t * venc = avccontext->priv_data;
@ -48,9 +142,8 @@ static int vorbis_encode_init(AVCodecContext * avccontext)
//if(avccontext->cutoff > 0) cfreq = avccontext->cutoff / 1000.0;
len = header.bytes + header_comm.bytes + header_code.bytes;
avccontext->extradata_size = 64 + len + len/255;
p = avccontext->extradata = av_mallocz(avccontext->extradata_size);
p = avccontext->extradata = av_mallocz(64 + len + len/255);
p[0] = 2;
offset = 1;
offset += av_xiphlacing(&p[offset], header.bytes);
@ -62,7 +155,6 @@ static int vorbis_encode_init(AVCodecContext * avccontext)
memcpy(&p[offset], header_code.packet, header_code.bytes);
offset += header_code.bytes;
avccontext->extradata_size = offset;
avccontext->extradata = av_realloc(avccontext->extradata, avccontext->extradata_size);
avccontext->frame_size = VORBIS_FRAME_SIZE;