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Trellis quantization support for adpcm_swf.

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Originally committed as revision 10144 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Benjamin Larsson 2007-08-19 20:31:53 +00:00
parent 7b07d3e8fe
commit 1cbe9d6a78
1 changed files with 16 additions and 2 deletions
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18
libavcodec/adpcm.c
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@ -297,7 +297,7 @@ static void adpcm_compress_trellis(AVCodecContext *avctx, const short *samples,
nodes[0]->step = c->step_index;
nodes[0]->sample1 = c->sample1;
nodes[0]->sample2 = c->sample2;
if(version == CODEC_ID_ADPCM_IMA_WAV)
if((version == CODEC_ID_ADPCM_IMA_WAV) || (version == CODEC_ID_ADPCM_SWF))
nodes[0]->sample1 = c->prev_sample;
if(version == CODEC_ID_ADPCM_MS)
nodes[0]->step = c->idelta;
@ -368,7 +368,7 @@ static void adpcm_compress_trellis(AVCodecContext *avctx, const short *samples,
next_##NAME:;
STORE_NODE(ms, FFMAX(16, (AdaptationTable[nibble] * step) >> 8));
}
} else if(version == CODEC_ID_ADPCM_IMA_WAV) {
} else if((version == CODEC_ID_ADPCM_IMA_WAV)|| (version == CODEC_ID_ADPCM_SWF)) {
#define LOOP_NODES(NAME, STEP_TABLE, STEP_INDEX)\
const int predictor = nodes[j]->sample1;\
const int div = (sample - predictor) * 4 / STEP_TABLE;\
@ -519,6 +519,8 @@ static int adpcm_encode_frame(AVCodecContext *avctx,
PutBitContext pb;
init_put_bits(&pb, dst, buf_size*8);
n = avctx->frame_size-1;
//Store AdpcmCodeSize
put_bits(&pb, 2, 2); //Set 4bits flash adpcm format
@ -530,10 +532,22 @@ static int adpcm_encode_frame(AVCodecContext *avctx,
c->status[i].prev_sample = (signed short)samples[i];
}
if(avctx->trellis > 0) {
uint8_t buf[2][n];
adpcm_compress_trellis(avctx, samples+2, buf[0], &c->status[0], n);
if (avctx->channels == 2)
adpcm_compress_trellis(avctx, samples+3, buf[1], &c->status[1], n);
for(i=0; i<n; i++) {
put_bits(&pb, 4, buf[0][i]);
if (avctx->channels == 2)
put_bits(&pb, 4, buf[1][i]);
}
} else {
for (i=1; i<avctx->frame_size; i++) {
put_bits(&pb, 4, adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels*i]) & 0xF);
if (avctx->channels == 2)
put_bits(&pb, 4, adpcm_ima_compress_sample(&c->status[1], samples[2*i+1]) & 0xF);
}
}
flush_put_bits(&pb);
dst += put_bits_count(&pb)>>3;