Chiebot-Mirror
/
FFmpeg
mirror of https://github.com/FFmpeg/FFmpeg.git
8
0
Fork 0
Code Issues Projects Releases Wiki Activity

VP8: optimized mv prediction and decoding

Browse Source 
Merge find_near_mvs and mv bitstream decoding: don't do prediction steps
until absolutely necessary.
oldabi
Jason Garrett-Glaser 14 years ago
parent 626264b11b
commit f3d09d44b7
1 changed files with 91 additions and 91 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 182
      libavcodec/vp8.c

182
libavcodec/vp8.c
Unescape View File

@ -528,68 +528,6 @@ void clamp_mv(VP8Context *s, VP56mv *dst, const VP56mv *src, int mb_x, int mb_y)
((s->mb_height - 1 - mb_y) << 6) + MARGIN);
}
static av_always_inline
void find_near_mvs(VP8Context *s, VP8Macroblock *mb,
VP56mv near[2], VP56mv *best, uint8_t cnt[4])
{
VP8Macroblock *mb_edge[3] = { mb + 2 /* top */,
mb - 1 /* left */,
mb + 1 /* top-left */ };
enum { EDGE_TOP, EDGE_LEFT, EDGE_TOPLEFT };
VP56mv near_mv[4] = {{ 0 }};
enum { CNT_ZERO, CNT_NEAREST, CNT_NEAR, CNT_SPLITMV };
int idx = CNT_ZERO;
int best_idx = CNT_ZERO;
int cur_sign_bias = s->sign_bias[mb->ref_frame];
int *sign_bias = s->sign_bias;
/* Process MB on top, left and top-left */
#define MV_EDGE_CHECK(n)\
{\
VP8Macroblock *edge = mb_edge[n];\
int edge_ref = edge->ref_frame;\
if (edge_ref != VP56_FRAME_CURRENT) {\
uint32_t mv = AV_RN32A(&edge->mv);\
if (mv) {\
if (cur_sign_bias != sign_bias[edge_ref]) {\
/* SWAR negate of the values in mv. */\
mv = ~mv;\
mv = ((mv&0x7fff7fff) + 0x00010001) ^ (mv&0x80008000);\
}\
if (!n || mv != AV_RN32A(&near_mv[idx]))\
AV_WN32A(&near_mv[++idx], mv);\
cnt[idx] += 1 + (n != 2);\
} else\
cnt[CNT_ZERO] += 1 + (n != 2);\
}\
}
MV_EDGE_CHECK(0)
MV_EDGE_CHECK(1)
MV_EDGE_CHECK(2)
/* If we have three distinct MVs, merge first and last if they're the same */
if (cnt[CNT_SPLITMV] && AV_RN32A(&near_mv[1+EDGE_TOP]) == AV_RN32A(&near_mv[1+EDGE_TOPLEFT]))
cnt[CNT_NEAREST] += 1;
cnt[CNT_SPLITMV] = ((mb_edge[EDGE_LEFT]->mode == VP8_MVMODE_SPLIT) +
(mb_edge[EDGE_TOP]->mode == VP8_MVMODE_SPLIT)) * 2 +
(mb_edge[EDGE_TOPLEFT]->mode == VP8_MVMODE_SPLIT);
/* Swap near and nearest if necessary */
if (cnt[CNT_NEAR] > cnt[CNT_NEAREST]) {
FFSWAP(uint8_t, cnt[CNT_NEAREST], cnt[CNT_NEAR]);
FFSWAP( VP56mv, near_mv[CNT_NEAREST], near_mv[CNT_NEAR]);
}
/* Choose the best mv out of 0,0 and the nearest mv */
if (cnt[CNT_NEAREST] >= cnt[CNT_ZERO])
best_idx = CNT_NEAREST;
mb->mv = near_mv[best_idx];
near[0] = near_mv[CNT_NEAREST];
near[1] = near_mv[CNT_NEAR];
}
/**
* Motion vector coding, 17.1.
*/
@ -699,6 +637,96 @@ int decode_splitmvs(VP8Context *s, VP56RangeCoder *c, VP8Macroblock *mb)
return num;
}
static av_always_inline
void decode_mvs(VP8Context *s, VP8Macroblock *mb, int mb_x, int mb_y)
{
VP8Macroblock *mb_edge[3] = { mb + 2 /* top */,
mb - 1 /* left */,
mb + 1 /* top-left */ };
enum { CNT_ZERO, CNT_NEAREST, CNT_NEAR, CNT_SPLITMV };
enum { EDGE_TOP, EDGE_LEFT, EDGE_TOPLEFT };
int idx = CNT_ZERO;
int cur_sign_bias = s->sign_bias[mb->ref_frame];
int *sign_bias = s->sign_bias;
VP56mv near_mv[4];
uint8_t cnt[4] = { 0 };
VP56RangeCoder *c = &s->c;
AV_ZERO32(&near_mv[0]);
AV_ZERO32(&near_mv[1]);
AV_ZERO32(&near_mv[2]);
/* Process MB on top, left and top-left */
#define MV_EDGE_CHECK(n)\
{\
VP8Macroblock *edge = mb_edge[n];\
int edge_ref = edge->ref_frame;\
if (edge_ref != VP56_FRAME_CURRENT) {\
uint32_t mv = AV_RN32A(&edge->mv);\
if (mv) {\
if (cur_sign_bias != sign_bias[edge_ref]) {\
/* SWAR negate of the values in mv. */\
mv = ~mv;\
mv = ((mv&0x7fff7fff) + 0x00010001) ^ (mv&0x80008000);\
}\
if (!n || mv != AV_RN32A(&near_mv[idx]))\
AV_WN32A(&near_mv[++idx], mv);\
cnt[idx] += 1 + (n != 2);\
} else\
cnt[CNT_ZERO] += 1 + (n != 2);\
}\
}
MV_EDGE_CHECK(0)
MV_EDGE_CHECK(1)
MV_EDGE_CHECK(2)
mb->partitioning = VP8_SPLITMVMODE_NONE;
if (vp56_rac_get_prob_branchy(c, vp8_mode_contexts[cnt[CNT_ZERO]][0])) {
mb->mode = VP8_MVMODE_MV;
/* If we have three distinct MVs, merge first and last if they're the same */
if (cnt[CNT_SPLITMV] && AV_RN32A(&near_mv[1+EDGE_TOP]) == AV_RN32A(&near_mv[1+EDGE_TOPLEFT]))
cnt[CNT_NEAREST] += 1;
/* Swap near and nearest if necessary */
if (cnt[CNT_NEAR] > cnt[CNT_NEAREST]) {
FFSWAP(uint8_t, cnt[CNT_NEAREST], cnt[CNT_NEAR]);
FFSWAP( VP56mv, near_mv[CNT_NEAREST], near_mv[CNT_NEAR]);
}
if (vp56_rac_get_prob_branchy(c, vp8_mode_contexts[cnt[CNT_NEAREST]][1])) {
if (vp56_rac_get_prob_branchy(c, vp8_mode_contexts[cnt[CNT_NEAR]][2])) {
/* Choose the best mv out of 0,0 and the nearest mv */
clamp_mv(s, &mb->mv, &near_mv[CNT_ZERO + (cnt[CNT_NEAREST] >= cnt[CNT_ZERO])], mb_x, mb_y);
cnt[CNT_SPLITMV] = ((mb_edge[EDGE_LEFT]->mode == VP8_MVMODE_SPLIT) +
(mb_edge[EDGE_TOP]->mode == VP8_MVMODE_SPLIT)) * 2 +
(mb_edge[EDGE_TOPLEFT]->mode == VP8_MVMODE_SPLIT);
if (vp56_rac_get_prob_branchy(c, vp8_mode_contexts[cnt[CNT_SPLITMV]][3])) {
mb->mode = VP8_MVMODE_SPLIT;
mb->mv = mb->bmv[decode_splitmvs(s, c, mb) - 1];
} else {
mb->mv.y += read_mv_component(c, s->prob->mvc[0]);
mb->mv.x += read_mv_component(c, s->prob->mvc[1]);
mb->bmv[0] = mb->mv;
}
} else {
clamp_mv(s, &mb->mv, &near_mv[CNT_NEAR], mb_x, mb_y);
mb->bmv[0] = mb->mv;
}
} else {
clamp_mv(s, &mb->mv, &near_mv[CNT_NEAREST], mb_x, mb_y);
mb->bmv[0] = mb->mv;
}
} else {
mb->mode = VP8_MVMODE_ZERO;
AV_ZERO32(&mb->mv);
mb->bmv[0] = mb->mv;
}
}
static av_always_inline
void decode_intra4x4_modes(VP8Context *s, VP56RangeCoder *c,
int mb_x, int keyframe)
@ -749,9 +777,6 @@ void decode_mb_mode(VP8Context *s, VP8Macroblock *mb, int mb_x, int mb_y, uint8_
s->chroma_pred_mode = vp8_rac_get_tree(c, vp8_pred8x8c_tree, vp8_pred8x8c_prob_intra);
mb->ref_frame = VP56_FRAME_CURRENT;
} else if (vp56_rac_get_prob_branchy(c, s->prob->intra)) {
VP56mv near[2], best;
uint8_t cnt[4] = { 0 };
// inter MB, 16.2
if (vp56_rac_get_prob_branchy(c, s->prob->last))
mb->ref_frame = vp56_rac_get_prob(c, s->prob->golden) ?
@ -761,32 +786,7 @@ void decode_mb_mode(VP8Context *s, VP8Macroblock *mb, int mb_x, int mb_y, uint8_
s->ref_count[mb->ref_frame-1]++;
// motion vectors, 16.3
find_near_mvs(s, mb, near, &best, cnt);
if (vp56_rac_get_prob_branchy(c, vp8_mode_contexts[cnt[0]][0])) {
mb->mode = VP8_MVMODE_MV;
if (vp56_rac_get_prob_branchy(c, vp8_mode_contexts[cnt[1]][1])) {
if (vp56_rac_get_prob_branchy(c, vp8_mode_contexts[cnt[2]][2])) {
if (vp56_rac_get_prob_branchy(c, vp8_mode_contexts[cnt[3]][3])) {
mb->mode = VP8_MVMODE_SPLIT;
clamp_mv(s, &mb->mv, &mb->mv, mb_x, mb_y);
mb->mv = mb->bmv[decode_splitmvs(s, c, mb) - 1];
} else {
clamp_mv(s, &mb->mv, &mb->mv, mb_x, mb_y);
mb->mv.y += read_mv_component(c, s->prob->mvc[0]);
mb->mv.x += read_mv_component(c, s->prob->mvc[1]);
}
} else
clamp_mv(s, &mb->mv, &near[1], mb_x, mb_y);
} else
clamp_mv(s, &mb->mv, &near[0], mb_x, mb_y);
} else {
mb->mode = VP8_MVMODE_ZERO;
AV_ZERO32(&mb->mv);
}
if (mb->mode != VP8_MVMODE_SPLIT) {
mb->partitioning = VP8_SPLITMVMODE_NONE;
mb->bmv[0] = mb->mv;
}
decode_mvs(s, mb, mb_x, mb_y);
} else {
// intra MB, 16.1
mb->mode = vp8_rac_get_tree(c, vp8_pred16x16_tree_inter, s->prob->pred16x16);

Write Preview
Loading…
Cancel
Save