[FFmpeg-cvslog] libavcodec/mpeg12: Remove "fast" mode
Kieran Kunhya
git at videolan.org
Mon Oct 30 00:49:36 EET 2023
ffmpeg | branch: master | Kieran Kunhya <kierank at obe.tv> | Sun Oct 29 15:32:49 2023 +0000| [7d497a1119b1525c32fa0a342329898e7c3f5373] | committer: Kieran Kunhya
libavcodec/mpeg12: Remove "fast" mode
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=7d497a1119b1525c32fa0a342329898e7c3f5373
---
libavcodec/mpeg12dec.c | 265 -------------------------------------------------
1 file changed, 265 deletions(-)
diff --git a/libavcodec/mpeg12dec.c b/libavcodec/mpeg12dec.c
index 5dac83ebcd..d266dfcef3 100644
--- a/libavcodec/mpeg12dec.c
+++ b/libavcodec/mpeg12dec.c
@@ -233,94 +233,6 @@ end:
return 0;
}
-/**
- * Changing this would eat up any speed benefits it has.
- * Do not use "fast" flag if you need the code to be robust.
- */
-static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s,
- int16_t *block, int n)
-{
- int level, i, j, run;
- uint8_t *const scantable = s->intra_scantable.permutated;
- const int qscale = s->qscale;
-
- {
- OPEN_READER(re, &s->gb);
- i = -1;
- // Special case for first coefficient, no need to add second VLC table.
- UPDATE_CACHE(re, &s->gb);
- if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
- level = (3 * qscale) >> 1;
- level = (level - 1) | 1;
- if (GET_CACHE(re, &s->gb) & 0x40000000)
- level = -level;
- block[0] = level;
- i++;
- SKIP_BITS(re, &s->gb, 2);
- if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
- goto end;
- }
-
- /* now quantify & encode AC coefficients */
- for (;;) {
- GET_RL_VLC(level, run, re, &s->gb, ff_mpeg1_rl_vlc,
- TEX_VLC_BITS, 2, 0);
-
- if (level != 0) {
- i += run;
- if (i > MAX_INDEX)
- break;
- j = scantable[i];
- level = ((level * 2 + 1) * qscale) >> 1;
- level = (level - 1) | 1;
- level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
- SHOW_SBITS(re, &s->gb, 1);
- SKIP_BITS(re, &s->gb, 1);
- } else {
- /* escape */
- run = SHOW_UBITS(re, &s->gb, 6) + 1;
- LAST_SKIP_BITS(re, &s->gb, 6);
- UPDATE_CACHE(re, &s->gb);
- level = SHOW_SBITS(re, &s->gb, 8);
- SKIP_BITS(re, &s->gb, 8);
- if (level == -128) {
- level = SHOW_UBITS(re, &s->gb, 8) - 256;
- SKIP_BITS(re, &s->gb, 8);
- } else if (level == 0) {
- level = SHOW_UBITS(re, &s->gb, 8);
- SKIP_BITS(re, &s->gb, 8);
- }
- i += run;
- if (i > MAX_INDEX)
- break;
- j = scantable[i];
- if (level < 0) {
- level = -level;
- level = ((level * 2 + 1) * qscale) >> 1;
- level = (level - 1) | 1;
- level = -level;
- } else {
- level = ((level * 2 + 1) * qscale) >> 1;
- level = (level - 1) | 1;
- }
- }
-
- block[j] = level;
- if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
- break;
- UPDATE_CACHE(re, &s->gb);
- }
-end:
- LAST_SKIP_BITS(re, &s->gb, 2);
- CLOSE_READER(re, &s->gb);
- }
-
- check_scantable_index(s, i);
-
- s->block_last_index[n] = i;
- return 0;
-}
-
static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
int16_t *block, int n)
{
@@ -406,81 +318,6 @@ end:
return 0;
}
-/**
- * Changing this would eat up any speed benefits it has.
- * Do not use "fast" flag if you need the code to be robust.
- */
-static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
- int16_t *block, int n)
-{
- int level, i, j, run;
- uint8_t *const scantable = s->intra_scantable.permutated;
- const int qscale = s->qscale;
- OPEN_READER(re, &s->gb);
- i = -1;
-
- // special case for first coefficient, no need to add second VLC table
- UPDATE_CACHE(re, &s->gb);
- if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
- level = (3 * qscale) >> 1;
- if (GET_CACHE(re, &s->gb) & 0x40000000)
- level = -level;
- block[0] = level;
- i++;
- SKIP_BITS(re, &s->gb, 2);
- if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
- goto end;
- }
-
- /* now quantify & encode AC coefficients */
- for (;;) {
- GET_RL_VLC(level, run, re, &s->gb, ff_mpeg1_rl_vlc, TEX_VLC_BITS, 2, 0);
-
- if (level != 0) {
- i += run;
- if (i > MAX_INDEX)
- break;
- j = scantable[i];
- level = ((level * 2 + 1) * qscale) >> 1;
- level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
- SHOW_SBITS(re, &s->gb, 1);
- SKIP_BITS(re, &s->gb, 1);
- } else {
- /* escape */
- run = SHOW_UBITS(re, &s->gb, 6) + 1;
- LAST_SKIP_BITS(re, &s->gb, 6);
- UPDATE_CACHE(re, &s->gb);
- level = SHOW_SBITS(re, &s->gb, 12);
- SKIP_BITS(re, &s->gb, 12);
-
- i += run;
- if (i > MAX_INDEX)
- break;
- j = scantable[i];
- if (level < 0) {
- level = ((-level * 2 + 1) * qscale) >> 1;
- level = -level;
- } else {
- level = ((level * 2 + 1) * qscale) >> 1;
- }
- }
-
- block[j] = level;
- if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF || i > 63)
- break;
-
- UPDATE_CACHE(re, &s->gb);
- }
-end:
- LAST_SKIP_BITS(re, &s->gb, 2);
- CLOSE_READER(re, &s->gb);
-
- check_scantable_index(s, i);
-
- s->block_last_index[n] = i;
- return 0;
-}
-
static inline int mpeg2_decode_block_intra(MpegEncContext *s,
int16_t *block, int n)
{
@@ -563,83 +400,6 @@ static inline int mpeg2_decode_block_intra(MpegEncContext *s,
return 0;
}
-/**
- * Changing this would eat up any speed benefits it has.
- * Do not use "fast" flag if you need the code to be robust.
- */
-static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
- int16_t *block, int n)
-{
- int level, dc, diff, i, j, run;
- int component;
- const RL_VLC_ELEM *rl_vlc;
- uint8_t *const scantable = s->intra_scantable.permutated;
- const uint16_t *quant_matrix;
- const int qscale = s->qscale;
-
- /* DC coefficient */
- if (n < 4) {
- quant_matrix = s->intra_matrix;
- component = 0;
- } else {
- quant_matrix = s->chroma_intra_matrix;
- component = (n & 1) + 1;
- }
- diff = decode_dc(&s->gb, component);
- dc = s->last_dc[component];
- dc += diff;
- s->last_dc[component] = dc;
- block[0] = dc * (1 << (3 - s->intra_dc_precision));
- i = 0;
- if (s->intra_vlc_format)
- rl_vlc = ff_mpeg2_rl_vlc;
- else
- rl_vlc = ff_mpeg1_rl_vlc;
-
- {
- OPEN_READER(re, &s->gb);
- /* now quantify & encode AC coefficients */
- for (;;) {
- UPDATE_CACHE(re, &s->gb);
- GET_RL_VLC(level, run, re, &s->gb, rl_vlc,
- TEX_VLC_BITS, 2, 0);
-
- if (level >= 64 || i > 63) {
- break;
- } else if (level != 0) {
- i += run;
- j = scantable[i];
- level = (level * qscale * quant_matrix[j]) >> 4;
- level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
- SHOW_SBITS(re, &s->gb, 1);
- LAST_SKIP_BITS(re, &s->gb, 1);
- } else {
- /* escape */
- run = SHOW_UBITS(re, &s->gb, 6) + 1;
- SKIP_BITS(re, &s->gb, 6);
- level = SHOW_SBITS(re, &s->gb, 12);
- LAST_SKIP_BITS(re, &s->gb, 12);
- i += run;
- j = scantable[i];
- if (level < 0) {
- level = (-level * qscale * quant_matrix[j]) >> 4;
- level = -level;
- } else {
- level = (level * qscale * quant_matrix[j]) >> 4;
- }
- }
-
- block[j] = level;
- }
- CLOSE_READER(re, &s->gb);
- }
-
- check_scantable_index(s, i);
-
- s->block_last_index[n] = i;
- return 0;
-}
-
/******************************************/
/* decoding */
@@ -767,14 +527,9 @@ static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
s->mb_intra = 1;
if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
- if (s->avctx->flags2 & AV_CODEC_FLAG2_FAST) {
- for (i = 0; i < 6; i++)
- mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
- } else {
for (i = 0; i < mb_block_count; i++)
if ((ret = mpeg2_decode_block_intra(s, *s->pblocks[i], i)) < 0)
return ret;
- }
} else {
for (i = 0; i < 6; i++) {
ret = ff_mpeg1_decode_block_intra(&s->gb,
@@ -994,15 +749,6 @@ static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
}
if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
- if (s->avctx->flags2 & AV_CODEC_FLAG2_FAST) {
- for (i = 0; i < 6; i++) {
- if (cbp & 32)
- mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
- else
- s->block_last_index[i] = -1;
- cbp += cbp;
- }
- } else {
cbp <<= 12 - mb_block_count;
for (i = 0; i < mb_block_count; i++) {
@@ -1014,17 +760,7 @@ static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
}
cbp += cbp;
}
- }
} else {
- if (s->avctx->flags2 & AV_CODEC_FLAG2_FAST) {
- for (i = 0; i < 6; i++) {
- if (cbp & 32)
- mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
- else
- s->block_last_index[i] = -1;
- cbp += cbp;
- }
- } else {
for (i = 0; i < 6; i++) {
if (cbp & 32) {
if ((ret = mpeg1_decode_block_inter(s, *s->pblocks[i], i)) < 0)
@@ -1034,7 +770,6 @@ static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
}
cbp += cbp;
}
- }
}
} else {
for (i = 0; i < 12; i++)
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