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authorChris Flerackers <cflerackers@androme.be>2004-07-22 10:23:28 +0000
committerMichael Niedermayer <michaelni@gmx.at>2004-07-22 10:23:28 +0000
commit7344c87aa9786936eebe366c929c8e854c857d5c (patch)
tree1847e2f1b0f99417a30703d83f8ac2a68e5431e2 /libavcodec/h261.c
parent0a38bafdcdfe69dc14bce054e92f4dbd0283743c (diff)
downloadffmpeg-7344c87aa9786936eebe366c929c8e854c857d5c.tar.gz
- 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
Diffstat (limited to 'libavcodec/h261.c')
-rw-r--r--libavcodec/h261.c82
1 files changed, 47 insertions, 35 deletions
diff --git a/libavcodec/h261.c b/libavcodec/h261.c
index ef4697a0cf..619a724360 100644
--- a/libavcodec/h261.c
+++ b/libavcodec/h261.c
@@ -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;