[FFmpeg-devel] [PATCH 59/67] avcodec/h261dec: Unquantize coefficients while parsing them
Andreas Rheinhardt
andreas.rheinhardt at outlook.com
Fri Jun 14 21:25:50 EEST 2024
This is beneficial for performance: When concatenating
the file from the vsynth1-h261 fate-test 100 times,
performance (measured by timing the codec's decode callback)
improved by 9.6%.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
---
libavcodec/h261dec.c | 11 +++++++++--
libavcodec/mpegvideo_dec.c | 11 ++++++-----
libavcodec/mpegvideo_enc.c | 2 +-
libavcodec/mpv_reconstruct_mb_template.c | 24 ++++++++++++------------
4 files changed, 28 insertions(+), 20 deletions(-)
diff --git a/libavcodec/h261dec.c b/libavcodec/h261dec.c
index f1c1e1a48a..6df8588bb6 100644
--- a/libavcodec/h261dec.c
+++ b/libavcodec/h261dec.c
@@ -244,6 +244,7 @@ static int h261_decode_block(H261DecContext *h, int16_t *block, int n, int coded
int level, i, j, run;
const RLTable *rl = &ff_h261_rl_tcoeff;
const uint8_t *scan_table;
+ const int qmul = s->qscale << 1, qadd = (s->qscale - 1) | 1;
/* For the variable length encoding there are two code tables, one being
* used for the first transmitted LEVEL in INTER, INTER + MC and
@@ -265,7 +266,7 @@ static int h261_decode_block(H261DecContext *h, int16_t *block, int n, int coded
* being coded as 1111 1111. */
if (level == 255)
level = 128;
- block[0] = level;
+ block[0] = level * s->y_dc_scale;
i = 1;
} else if (coded) {
// Run Level Code
@@ -276,7 +277,8 @@ static int h261_decode_block(H261DecContext *h, int16_t *block, int n, int coded
i = 0;
if (check & 0x2) {
skip_bits(&s->gb, 2);
- block[0] = (check & 0x1) ? -1 : 1;
+ block[0] = qmul + qadd;
+ block[0] *= (check & 0x1) ? -1 : 1;
i = 1;
}
} else {
@@ -306,10 +308,15 @@ static int h261_decode_block(H261DecContext *h, int16_t *block, int n, int coded
run = SHOW_UBITS(re, &s->gb, 6) + 1;
SKIP_CACHE(re, &s->gb, 6);
level = SHOW_SBITS(re, &s->gb, 8);
+ if (level > 0)
+ level = level * qmul + qadd;
+ else if (level < 0)
+ level = level * qmul - qadd;
SKIP_COUNTER(re, &s->gb, 6 + 8);
} else if (level == 0) {
break;
} else {
+ level = level * qmul + qadd;
if (SHOW_UBITS(re, &s->gb, 1))
level = -level;
SKIP_COUNTER(re, &s->gb, 1);
diff --git a/libavcodec/mpegvideo_dec.c b/libavcodec/mpegvideo_dec.c
index 684f31947c..da88a35120 100644
--- a/libavcodec/mpegvideo_dec.c
+++ b/libavcodec/mpegvideo_dec.c
@@ -927,15 +927,16 @@ void ff_mpv_reconstruct_mb(MpegEncContext *s, int16_t block[12][64])
}
}
+ av_assert2((s->out_format <= FMT_H261) == (s->out_format == FMT_H261 || s->out_format == FMT_MPEG1));
if (!s->avctx->lowres) {
#if !CONFIG_SMALL
- if (s->out_format == FMT_MPEG1)
- mpv_reconstruct_mb_internal(s, block, 0, DEFINITELY_MPEG12);
+ if (s->out_format <= FMT_H261)
+ mpv_reconstruct_mb_internal(s, block, 0, DEFINITELY_MPEG12_H261);
else
- mpv_reconstruct_mb_internal(s, block, 0, NOT_MPEG12);
+ mpv_reconstruct_mb_internal(s, block, 0, NOT_MPEG12_H261);
#else
- mpv_reconstruct_mb_internal(s, block, 0, MAY_BE_MPEG12);
+ mpv_reconstruct_mb_internal(s, block, 0, MAY_BE_MPEG12_H261);
#endif
} else
- mpv_reconstruct_mb_internal(s, block, 1, MAY_BE_MPEG12);
+ mpv_reconstruct_mb_internal(s, block, 1, MAY_BE_MPEG12_H261);
}
diff --git a/libavcodec/mpegvideo_enc.c b/libavcodec/mpegvideo_enc.c
index 125d16e694..d05a93d249 100644
--- a/libavcodec/mpegvideo_enc.c
+++ b/libavcodec/mpegvideo_enc.c
@@ -1101,7 +1101,7 @@ static void mpv_reconstruct_mb(MpegEncContext *s, int16_t block[12][64])
}
}
- mpv_reconstruct_mb_internal(s, block, 0, MAY_BE_MPEG12);
+ mpv_reconstruct_mb_internal(s, block, 0, MAY_BE_MPEG12_H261);
}
static int get_sae(const uint8_t *src, int ref, int stride)
diff --git a/libavcodec/mpv_reconstruct_mb_template.c b/libavcodec/mpv_reconstruct_mb_template.c
index 4b16974827..dca982ae0f 100644
--- a/libavcodec/mpv_reconstruct_mb_template.c
+++ b/libavcodec/mpv_reconstruct_mb_template.c
@@ -20,9 +20,9 @@
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
-#define NOT_MPEG12 0
-#define MAY_BE_MPEG12 1
-#define DEFINITELY_MPEG12 2
+#define NOT_MPEG12_H261 0
+#define MAY_BE_MPEG12_H261 1
+#define DEFINITELY_MPEG12_H261 2
/* put block[] to dest[] */
static inline void put_dct(MpegEncContext *s,
@@ -56,14 +56,14 @@ static av_always_inline
void mpv_reconstruct_mb_internal(MpegEncContext *s, int16_t block[12][64],
int lowres_flag, int is_mpeg12)
{
-#define IS_MPEG12(s) (is_mpeg12 == MAY_BE_MPEG12 ? ((s)->out_format == FMT_MPEG1) : is_mpeg12)
+#define IS_MPEG12_H261(s) (is_mpeg12 == MAY_BE_MPEG12_H261 ? ((s)->out_format <= FMT_H261) : is_mpeg12)
const int mb_xy = s->mb_y * s->mb_stride + s->mb_x;
s->cur_pic.qscale_table[mb_xy] = s->qscale;
/* update DC predictors for P macroblocks */
if (!s->mb_intra) {
- if (is_mpeg12 != DEFINITELY_MPEG12 && (s->h263_pred || s->h263_aic)) {
+ if (is_mpeg12 != DEFINITELY_MPEG12_H261 && (s->h263_pred || s->h263_aic)) {
if (s->mbintra_table[mb_xy])
ff_clean_intra_table_entries(s);
} else {
@@ -71,7 +71,7 @@ void mpv_reconstruct_mb_internal(MpegEncContext *s, int16_t block[12][64],
s->last_dc[1] =
s->last_dc[2] = 128 << s->intra_dc_precision;
}
- } else if (is_mpeg12 != DEFINITELY_MPEG12 && (s->h263_pred || s->h263_aic))
+ } else if (is_mpeg12 != DEFINITELY_MPEG12_H261 && (s->h263_pred || s->h263_aic))
s->mbintra_table[mb_xy] = 1;
#if IS_ENCODER
@@ -110,7 +110,7 @@ void mpv_reconstruct_mb_internal(MpegEncContext *s, int16_t block[12][64],
/* decoding or more than one mb_type (MC was already done otherwise) */
#if !IS_ENCODER
- if (HAVE_THREADS && is_mpeg12 != DEFINITELY_MPEG12 &&
+ if (HAVE_THREADS && is_mpeg12 != DEFINITELY_MPEG12_H261 &&
s->avctx->active_thread_type & FF_THREAD_FRAME) {
if (s->mv_dir & MV_DIR_FORWARD) {
ff_thread_progress_await(&s->last_pic.ptr->progress,
@@ -136,7 +136,7 @@ void mpv_reconstruct_mb_internal(MpegEncContext *s, int16_t block[12][64],
const op_pixels_func (*op_pix)[4];
const qpel_mc_func (*op_qpix)[16];
- if ((is_mpeg12 == DEFINITELY_MPEG12 || !s->no_rounding) || s->pict_type == AV_PICTURE_TYPE_B) {
+ if ((is_mpeg12 == DEFINITELY_MPEG12_H261 || !s->no_rounding) || s->pict_type == AV_PICTURE_TYPE_B) {
op_pix = s->hdsp.put_pixels_tab;
op_qpix = s->qdsp.put_qpel_pixels_tab;
} else {
@@ -162,7 +162,7 @@ void mpv_reconstruct_mb_internal(MpegEncContext *s, int16_t block[12][64],
}
/* add dct residue */
- if (!(IS_MPEG12(s) || s->msmpeg4_version != MSMP4_UNUSED ||
+ if (!(IS_MPEG12_H261(s) || s->msmpeg4_version != MSMP4_UNUSED ||
(s->codec_id == AV_CODEC_ID_MPEG4 && !s->mpeg_quant)))
#endif /* !IS_ENCODER */
{
@@ -187,7 +187,7 @@ void mpv_reconstruct_mb_internal(MpegEncContext *s, int16_t block[12][64],
}
}
#if !IS_ENCODER
- else if (is_mpeg12 == DEFINITELY_MPEG12 || lowres_flag || (s->codec_id != AV_CODEC_ID_WMV2)) {
+ else if (is_mpeg12 == DEFINITELY_MPEG12_H261 || lowres_flag || (s->codec_id != AV_CODEC_ID_WMV2)) {
add_dct(s, block[0], 0, dest_y , dct_linesize);
add_dct(s, block[1], 1, dest_y + block_size, dct_linesize);
add_dct(s, block[2], 2, dest_y + dct_offset , dct_linesize);
@@ -222,12 +222,12 @@ void mpv_reconstruct_mb_internal(MpegEncContext *s, int16_t block[12][64],
#if !IS_ENCODER
/* Only MPEG-4 Simple Studio Profile is supported in > 8-bit mode.
TODO: Integrate 10-bit properly into mpegvideo.c so that ER works properly */
- if (is_mpeg12 != DEFINITELY_MPEG12 && CONFIG_MPEG4_DECODER &&
+ if (is_mpeg12 != DEFINITELY_MPEG12_H261 && CONFIG_MPEG4_DECODER &&
/* s->codec_id == AV_CODEC_ID_MPEG4 && */
s->avctx->bits_per_raw_sample > 8) {
ff_mpeg4_decode_studio(s, dest_y, dest_cb, dest_cr, block_size,
uvlinesize, dct_linesize, dct_offset);
- } else if (!IS_MPEG12(s))
+ } else if (!IS_MPEG12_H261(s))
#endif /* !IS_ENCODER */
{
/* dct only in intra block */
--
2.40.1
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