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Simplify chroma AC in CABAC residual decoding. 

Originally committed as revision 16227 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Jason Garrett-Glaser 2008-12-19 00:43:30 +00:00
parent 8955b66950
commit b9fe706305
1 changed files with 8 additions and 19 deletions
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27
libavcodec/h264.c
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@ -5084,14 +5084,9 @@ static av_always_inline int get_cabac_cbf_ctx( H264Context *h, int cat, int idx,
nzb = (h-> top_cbp>>(6+idx))&0x01; nzb = (h-> top_cbp>>(6+idx))&0x01;
} }
} else { } else {
if( cat == 4 ) { assert(cat == 1 || cat == 2 || cat == 4);
nza = h->non_zero_count_cache[scan8[16+idx] - 1]; nza = h->non_zero_count_cache[scan8[idx] - 1];
nzb = h->non_zero_count_cache[scan8[16+idx] - 8]; nzb = h->non_zero_count_cache[scan8[idx] - 8];
} else {
assert(cat == 1 || cat == 2);
nza = h->non_zero_count_cache[scan8[idx] - 1];
nzb = h->non_zero_count_cache[scan8[idx] - 8];
}
} }
if( nza > 0 ) if( nza > 0 )
@ -5173,19 +5168,15 @@ static av_always_inline void decode_cabac_residual_internal( H264Context *h, DCT
* 1-> AC 16x16 n = luma4x4idx * 1-> AC 16x16 n = luma4x4idx
* 2-> Luma4x4 n = luma4x4idx * 2-> Luma4x4 n = luma4x4idx
* 3-> DC Chroma n = iCbCr * 3-> DC Chroma n = iCbCr
* 4-> AC Chroma n = 4 * iCbCr + chroma4x4idx * 4-> AC Chroma n = 16 + 4 * iCbCr + chroma4x4idx
* 5-> Luma8x8 n = 4 * luma8x8idx * 5-> Luma8x8 n = 4 * luma8x8idx
*/ */
/* read coded block flag */ /* read coded block flag */
if( is_dc || cat != 5 ) { if( is_dc || cat != 5 ) {
if( get_cabac( CC, &h->cabac_state[85 + get_cabac_cbf_ctx( h, cat, n, is_dc ) ] ) == 0 ) { if( get_cabac( CC, &h->cabac_state[85 + get_cabac_cbf_ctx( h, cat, n, is_dc ) ] ) == 0 ) {
if( !is_dc ) { if( !is_dc )
if( cat == 4 ) h->non_zero_count_cache[scan8[n]] = 0;
h->non_zero_count_cache[scan8[16+n]] = 0;
else
h->non_zero_count_cache[scan8[n]] = 0;
}
#ifdef CABAC_ON_STACK #ifdef CABAC_ON_STACK
h->cabac.range = cc.range ; h->cabac.range = cc.range ;
@ -5240,10 +5231,8 @@ static av_always_inline void decode_cabac_residual_internal( H264Context *h, DCT
} else { } else {
if( cat == 5 ) if( cat == 5 )
fill_rectangle(&h->non_zero_count_cache[scan8[n]], 2, 2, 8, coeff_count, 1); fill_rectangle(&h->non_zero_count_cache[scan8[n]], 2, 2, 8, coeff_count, 1);
else if( cat == 4 )
h->non_zero_count_cache[scan8[16+n]] = coeff_count;
else { else {
assert( cat == 1 || cat == 2 ); assert( cat == 1 || cat == 2 || cat == 4 );
h->non_zero_count_cache[scan8[n]] = coeff_count; h->non_zero_count_cache[scan8[n]] = coeff_count;
} }
} }
@ -5825,7 +5814,7 @@ decode_intra_mb:
for( i = 0; i < 4; i++ ) { for( i = 0; i < 4; i++ ) {
const int index = 16 + 4 * c + i; const int index = 16 + 4 * c + i;
//av_log( s->avctx, AV_LOG_ERROR, "INTRA C%d-AC %d\n",c, index - 16 ); //av_log( s->avctx, AV_LOG_ERROR, "INTRA C%d-AC %d\n",c, index - 16 );
decode_cabac_residual(h, h->mb + 16*index, 4, index - 16, scan + 1, qmul, 15); decode_cabac_residual(h, h->mb + 16*index, 4, index, scan + 1, qmul, 15);
} }
} }
} else { } else {