[FFmpeg-devel] [PATCH 09/10] lavc/hevc_ps: reduce the size of ShortTermRPS.used
Anton Khirnov
anton at khirnov.net
Wed Apr 10 16:31:17 EEST 2024
It is currently an array of 32 uint8_t, each storing a single flag. A
single uint32_t is sufficient.
Reduces sizeof(HEVCSPS) by 1792 bytes.
---
libavcodec/hevc_ps.c | 33 +++++++++++++++++++--------------
libavcodec/hevc_ps.h | 2 +-
libavcodec/hevc_refs.c | 6 +++---
libavcodec/vulkan_hevc.c | 8 ++++----
4 files changed, 27 insertions(+), 22 deletions(-)
diff --git a/libavcodec/hevc_ps.c b/libavcodec/hevc_ps.c
index a6b0021bc3..76fe507e7b 100644
--- a/libavcodec/hevc_ps.c
+++ b/libavcodec/hevc_ps.c
@@ -107,6 +107,7 @@ int ff_hevc_decode_short_term_rps(GetBitContext *gb, AVCodecContext *avctx,
int k = 0;
int i;
+ rps->used = 0;
rps->rps_predict = 0;
if (rps != sps->st_rps && sps->nb_st_rps)
@@ -114,6 +115,7 @@ int ff_hevc_decode_short_term_rps(GetBitContext *gb, AVCodecContext *avctx,
if (rps->rps_predict) {
const ShortTermRPS *rps_ridx;
+ uint8_t used[32] = { 0 };
int delta_rps;
if (is_slice_header) {
@@ -139,13 +141,13 @@ int ff_hevc_decode_short_term_rps(GetBitContext *gb, AVCodecContext *avctx,
}
delta_rps = (1 - (rps->delta_rps_sign << 1)) * rps->abs_delta_rps;
for (i = 0; i <= rps_ridx->num_delta_pocs; i++) {
- int used = rps->used[k] = get_bits1(gb);
+ used[k] = get_bits1(gb);
rps->use_delta_flag = 0;
- if (!used)
+ if (!used[k])
rps->use_delta_flag = get_bits1(gb);
- if (used || rps->use_delta_flag) {
+ if (used[k] || rps->use_delta_flag) {
if (i < rps_ridx->num_delta_pocs)
delta_poc = delta_rps + rps_ridx->delta_poc[i];
else
@@ -157,7 +159,7 @@ int ff_hevc_decode_short_term_rps(GetBitContext *gb, AVCodecContext *avctx,
}
}
- if (k >= FF_ARRAY_ELEMS(rps->used)) {
+ if (k >= FF_ARRAY_ELEMS(used)) {
av_log(avctx, AV_LOG_ERROR,
"Invalid num_delta_pocs: %d\n", k);
return AVERROR_INVALIDDATA;
@@ -167,35 +169,38 @@ int ff_hevc_decode_short_term_rps(GetBitContext *gb, AVCodecContext *avctx,
rps->num_negative_pics = k0;
// sort in increasing order (smallest first)
if (rps->num_delta_pocs != 0) {
- int used, tmp;
+ int u, tmp;
for (i = 1; i < rps->num_delta_pocs; i++) {
delta_poc = rps->delta_poc[i];
- used = rps->used[i];
+ u = used[i];
for (k = i - 1; k >= 0; k--) {
tmp = rps->delta_poc[k];
if (delta_poc < tmp) {
rps->delta_poc[k + 1] = tmp;
- rps->used[k + 1] = rps->used[k];
+ used[k + 1] = used[k];
rps->delta_poc[k] = delta_poc;
- rps->used[k] = used;
+ used[k] = u;
}
}
}
}
if ((rps->num_negative_pics >> 1) != 0) {
- int used;
+ int u;
k = rps->num_negative_pics - 1;
// flip the negative values to largest first
for (i = 0; i < rps->num_negative_pics >> 1; i++) {
delta_poc = rps->delta_poc[i];
- used = rps->used[i];
+ u = used[i];
rps->delta_poc[i] = rps->delta_poc[k];
- rps->used[i] = rps->used[k];
+ used[i] = used[k];
rps->delta_poc[k] = delta_poc;
- rps->used[k] = used;
+ used[k] = u;
k--;
}
}
+
+ for (unsigned i = 0; i < FF_ARRAY_ELEMS(used); i++)
+ rps->used |= used[i] * (1 << i);
} else {
unsigned int nb_positive_pics;
@@ -222,7 +227,7 @@ int ff_hevc_decode_short_term_rps(GetBitContext *gb, AVCodecContext *avctx,
}
prev -= delta_poc;
rps->delta_poc[i] = prev;
- rps->used[i] = get_bits1(gb);
+ rps->used |= get_bits1(gb) * (1 << i);
}
prev = 0;
for (i = 0; i < nb_positive_pics; i++) {
@@ -235,7 +240,7 @@ int ff_hevc_decode_short_term_rps(GetBitContext *gb, AVCodecContext *avctx,
}
prev += delta_poc;
rps->delta_poc[rps->num_negative_pics + i] = prev;
- rps->used[rps->num_negative_pics + i] = get_bits1(gb);
+ rps->used |= get_bits1(gb) * (1 << (rps->num_negative_pics + i));
}
}
}
diff --git a/libavcodec/hevc_ps.h b/libavcodec/hevc_ps.h
index 6ef29a8ea7..92b85115f7 100644
--- a/libavcodec/hevc_ps.h
+++ b/libavcodec/hevc_ps.h
@@ -79,7 +79,7 @@ typedef struct ShortTermRPS {
int num_delta_pocs;
int rps_idx_num_delta_pocs;
int32_t delta_poc[32];
- uint8_t used[32];
+ uint32_t used;
} ShortTermRPS;
typedef struct HEVCWindow {
diff --git a/libavcodec/hevc_refs.c b/libavcodec/hevc_refs.c
index aed649933d..19f3fa81da 100644
--- a/libavcodec/hevc_refs.c
+++ b/libavcodec/hevc_refs.c
@@ -501,7 +501,7 @@ int ff_hevc_frame_rps(HEVCContext *s)
int poc = s->poc + short_rps->delta_poc[i];
int list;
- if (!short_rps->used[i])
+ if (!(short_rps->used & (1 << i)))
list = ST_FOLL;
else if (i < short_rps->num_negative_pics)
list = ST_CURR_BEF;
@@ -540,9 +540,9 @@ int ff_hevc_frame_nb_refs(const HEVCContext *s)
if (rps) {
for (i = 0; i < rps->num_negative_pics; i++)
- ret += !!rps->used[i];
+ ret += !!(rps->used & (1 << i));
for (; i < rps->num_delta_pocs; i++)
- ret += !!rps->used[i];
+ ret += !!(rps->used & (1 << i));
}
if (long_rps) {
diff --git a/libavcodec/vulkan_hevc.c b/libavcodec/vulkan_hevc.c
index 5d7c6b1b64..c2b65fc201 100644
--- a/libavcodec/vulkan_hevc.c
+++ b/libavcodec/vulkan_hevc.c
@@ -374,17 +374,17 @@ static void set_sps(const HEVCSPS *sps, int sps_idx,
/* NOTE: This is the predicted, and *reordered* version.
* Probably incorrect, but the spec doesn't say which version to use. */
for (int j = 0; j < sps->st_rps[i].num_delta_pocs; j++)
- str[i].used_by_curr_pic_flag |= sps->st_rps[i].used[j] << j;
+ str[i].used_by_curr_pic_flag |= st_rps->used;
for (int j = 0; j < str[i].num_negative_pics; j++) {
- str[i].delta_poc_s0_minus1[j] = st_rps->delta_poc[j] - (j ? st_rps->delta_poc[j - 1] : 0) - 1;
- str[i].used_by_curr_pic_s0_flag |= sps->st_rps[i].used[j] << j;
+ str[i].delta_poc_s0_minus1[j] = st_rps->delta_poc[j] - (j ? st_rps->delta_poc[j - 1] : 0) - 1;
+ str[i].used_by_curr_pic_s0_flag |= st_rps->used & ((1 << str[i].num_negative_pics) - 1);
}
for (int j = 0; j < str[i].num_positive_pics; j++) {
str[i].delta_poc_s0_minus1[j] = st_rps->delta_poc[st_rps->num_negative_pics + j] -
(j ? st_rps->delta_poc[st_rps->num_negative_pics + j - 1] : 0) - 1;
- str[i].used_by_curr_pic_s0_flag |= sps->st_rps[i].used[str[i].num_negative_pics + j] << j;
+ str[i].used_by_curr_pic_s0_flag |= st_rps->used >> str[i].num_negative_pics;
}
}
--
2.43.0
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