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avcodec/vc1: fix mquant calculation

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In vc1_decode_i_blocks_adv mquant needs to be reset to its default value for
each macroblock, instead of once at the beginning of the slice.

DQPROFILE specifies which macroblocks can have an alternative quantizer step
size. When DQPROFILE specifies edges, the selection is applicable to the edges
of the picture. Slice edges are not selected by DQPROFILE.

Signed-off-by: Jerome Borsboom <jerome.borsboom@carpalis.nl>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Jerome Borsboom 2018-04-28 17:15:32 +02:00 committed by Michael Niedermayer
parent 29fd44adf1
commit 19c3df0cd6
1 changed files with 3 additions and 2 deletions
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5
libavcodec/vc1_block.c
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@ -177,7 +177,7 @@ static void vc1_put_signed_blocks_clamped(VC1Context *v)
edges = 15; \
if ((edges&1) && !s->mb_x) \
mquant = -v->altpq; \
if ((edges&2) && s->first_slice_line) \
if ((edges&2) && !s->mb_y) \
mquant = -v->altpq; \
if ((edges&4) && s->mb_x == (s->mb_width - 1)) \
mquant = -v->altpq; \
@ -2626,7 +2626,7 @@ static void vc1_decode_i_blocks_adv(VC1Context *v)
int cbp, val;
uint8_t *coded_val;
int mb_pos;
int mquant = v->pq;
int mquant;
int mqdiff;
GetBitContext *gb = &s->gb;
@ -2671,6 +2671,7 @@ static void vc1_decode_i_blocks_adv(VC1Context *v)
init_block_index(v);
for (;s->mb_x < s->mb_width; s->mb_x++) {
int16_t (*block)[64] = v->block[v->cur_blk_idx];
mquant = v->pq;
ff_update_block_index(s);
s->bdsp.clear_blocks(block[0]);
mb_pos = s->mb_x + s->mb_y * s->mb_stride;