- Support empty GOB's (no mb's) and skip all mb's

- Mb's were not skipped at the end of a GOB
- One value too much was used in iDCT
- Chroma_qscale was not updated for mquant
patch by ("Chris Flerackers" <cflerackers at androme dot be>)

Originally committed as revision 3332 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Chris Flerackers 2004-07-22 10:23:28 +00:00 committed by Michael Niedermayer
parent 0a38bafdcd
commit 7344c87aa9

View File

@ -207,24 +207,39 @@ static int ff_h261_resync(H261Context *h){
}
/**
* decodes a skipped macroblock, called when when mba_diff > 1.
* decodes skipped macroblocks
* @return 0
*/
static int h261_decode_mb_skipped(H261Context *h,
DCTELEM block[6][64])
static int h261_decode_mb_skipped(H261Context *h, int mba1, int mba2 )
{
MpegEncContext * const s = &h->s;
int i;
const int xy = s->mb_x + s->mb_y * s->mb_stride;
s->mb_intra = 0;
for(i=0;i<6;i++)
s->block_last_index[i] = -1;
s->mv_dir = MV_DIR_FORWARD;
s->mv_type = MV_TYPE_16X16;
s->current_picture.mb_type[xy]= MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
s->mv[0][0][0] = 0;
s->mv[0][0][1] = 0;
s->mb_skiped = 1;
for(i=mba1; i<mba2; i++){
int j, xy;
s->mb_x= ((h->gob_number-1) % 2) * 11 + i % 11;
s->mb_y= ((h->gob_number-1) / 2) * 3 + i / 11;
xy = s->mb_x + s->mb_y * s->mb_stride;
ff_init_block_index(s);
ff_update_block_index(s);
s->dsp.clear_blocks(s->block[0]);
for(j=0;j<6;j++)
s->block_last_index[j] = -1;
s->mv_dir = MV_DIR_FORWARD;
s->mv_type = MV_TYPE_16X16;
s->current_picture.mb_type[xy]= MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
s->mv[0][0][0] = 0;
s->mv[0][0][1] = 0;
s->mb_skiped = 1;
MPV_decode_mb(s, s->block);
}
return 0;
}
@ -270,6 +285,7 @@ static int h261_decode_mb(H261Context *h,
ff_init_block_index(s);
ff_update_block_index(s);
s->dsp.clear_blocks(s->block[0]);
// Read mtype
old_mtype = h->mtype;
@ -281,7 +297,7 @@ static int h261_decode_mb(H261Context *h,
// Read mquant
if ( IS_QUANT ( h->mtype ) ){
s->qscale = get_bits(&s->gb, 5);
ff_set_qscale(s, get_bits(&s->gb, 5));
}
s->mb_intra = IS_INTRA4x4(h->mtype);
@ -432,7 +448,7 @@ static int h261_decode_block(H261Context * h, DCTELEM * block,
block[j] = level;
i++;
}
s->block_last_index[n] = i;
s->block_last_index[n] = i-1;
return 0;
}
@ -508,14 +524,26 @@ int h261_decode_picture_header(H261Context *h){
static int h261_decode_gob(H261Context *h){
MpegEncContext * const s = &h->s;
int i;
ff_set_qscale(s, s->qscale);
/* check for empty gob */
int v= show_bits(&s->gb, 15);
if(get_bits_count(&s->gb) + 15 > s->gb.size_in_bits){
v>>= get_bits_count(&s->gb) + 15 - s->gb.size_in_bits;
}
if(v==0){
h261_decode_mb_skipped(h, 0, 33);
return 0;
}
/* decode mb's */
while(h->current_mba <= MAX_MBA)
{
int ret;
/* DCT & quantize */
s->dsp.clear_blocks(s->block[0]);
ret= h261_decode_mb(h, s->block);
if(ret<0){
const int xy= s->mb_x + s->mb_y*s->mb_stride;
@ -525,16 +553,8 @@ static int h261_decode_gob(H261Context *h){
ff_h261_loop_filter(h);
}
h->loop_filter = 0;
for(i=1; i<h->mba_diff; i++){
s->mb_x= ((h->gob_number-1) % 2) * 11 + ((h->current_mba-1-i) % 11);
s->mb_y= ((h->gob_number-1) / 2) * 3 + ((h->current_mba-1-i) / 11);
ff_init_block_index(s);
ff_update_block_index(s);
s->dsp.clear_blocks(s->block[0]);
ret= h261_decode_mb_skipped(h, s->block);
MPV_decode_mb(s, s->block);
}
h261_decode_mb_skipped(h, h->current_mba-h->mba_diff, h->current_mba-1);
h261_decode_mb_skipped(h, h->current_mba, 33);
return 0;
}else if(ret==SLICE_NOEND){
av_log(s->avctx, AV_LOG_ERROR, "Slice mismatch at MB: %d\n", xy);
@ -549,15 +569,7 @@ static int h261_decode_gob(H261Context *h){
}
h->loop_filter = 0;
for(i=1; i<h->mba_diff; i++){
s->mb_x= ((h->gob_number-1) % 2) * 11 + ((h->current_mba-1-i) % 11);
s->mb_y= ((h->gob_number-1) / 2) * 3 + ((h->current_mba-1-i) / 11);
ff_init_block_index(s);
ff_update_block_index(s);
s->dsp.clear_blocks(s->block[0]);
ret= h261_decode_mb_skipped(h, s->block);
MPV_decode_mb(s, s->block);
}
h261_decode_mb_skipped(h, h->current_mba-h->mba_diff, h->current_mba-1);
}
return -1;