[FFmpeg-devel] [PATCH] h264: don't store intra pcm samples in h->mb.
Ronald S. Bultje
rsbultje at gmail.com
Sat Feb 16 18:35:12 CET 2013
From: "Ronald S. Bultje" <rsbultje at gmail.com>
Instead, keep them in the bitstream buffer until we read them verbatim,
this saves a memcpy() and a subsequent clearing of the target buffer.
decode_cabac+decode_mb for a sample file (CAPM3_Sony_D.jsv) goes from
6121.4 to 6095.5 cycles, i.e. 26 cycles faster.
---
libavcodec/h264.c | 2 +-
libavcodec/h264.h | 1 +
libavcodec/h264_cabac.c | 3 ++-
libavcodec/h264_cavlc.c | 11 +++--------
libavcodec/h264_mb_template.c | 29 +++++++++++++++--------------
5 files changed, 22 insertions(+), 24 deletions(-)
diff --git a/libavcodec/h264.c b/libavcodec/h264.c
index 792e3e1..b0dd780 100644
--- a/libavcodec/h264.c
+++ b/libavcodec/h264.c
@@ -1253,7 +1253,7 @@ static int decode_update_thread_context(AVCodecContext *dst,
// copy all fields after MpegEnc, except mb
memcpy(&h->s + 1, &h1->s + 1,
- offsetof(H264Context, mb) - sizeof(MpegEncContext));
+ offsetof(H264Context, intra_pcm_ptr) - sizeof(MpegEncContext));
av_assert0(&h->cabac == &h->mb_padding + 1);
memcpy(&h->cabac, &h1->cabac,
sizeof(H264Context) - offsetof(H264Context, cabac));
diff --git a/libavcodec/h264.h b/libavcodec/h264.h
index b0d44cc..cfb8170 100644
--- a/libavcodec/h264.h
+++ b/libavcodec/h264.h
@@ -390,6 +390,7 @@ typedef struct H264Context {
GetBitContext *intra_gb_ptr;
GetBitContext *inter_gb_ptr;
+ const uint8_t *intra_pcm_ptr;
DECLARE_ALIGNED(16, int16_t, mb)[16 * 48 * 2]; ///< as a dct coeffecient is int32_t in high depth, we need to reserve twice the space.
DECLARE_ALIGNED(16, int16_t, mb_luma_dc)[3][16 * 2];
int16_t mb_padding[256 * 2]; ///< as mb is addressed by scantable[i] and scantable is uint8_t we can either check that i is not too large or ensure that there is some unused stuff after mb
diff --git a/libavcodec/h264_cabac.c b/libavcodec/h264_cabac.c
index 54b3775..015f948 100644
--- a/libavcodec/h264_cabac.c
+++ b/libavcodec/h264_cabac.c
@@ -2009,7 +2009,8 @@ decode_intra_mb:
// The pixels are stored in the same order as levels in h->mb array.
if ((int) (h->cabac.bytestream_end - ptr) < mb_size)
return -1;
- memcpy(h->mb, ptr, mb_size); ptr+=mb_size;
+ h->intra_pcm_ptr = ptr;
+ ptr += mb_size;
ff_init_cabac_decoder(&h->cabac, ptr, h->cabac.bytestream_end - ptr);
diff --git a/libavcodec/h264_cavlc.c b/libavcodec/h264_cavlc.c
index 7ca2bb2..8f1dd80 100644
--- a/libavcodec/h264_cavlc.c
+++ b/libavcodec/h264_cavlc.c
@@ -765,17 +765,12 @@ decode_intra_mb:
h->slice_table[ mb_xy ]= h->slice_num;
if(IS_INTRA_PCM(mb_type)){
- unsigned int x;
const int mb_size = ff_h264_mb_sizes[h->sps.chroma_format_idc] *
- h->sps.bit_depth_luma >> 3;
+ h->sps.bit_depth_luma;
// We assume these blocks are very rare so we do not optimize it.
- align_get_bits(&s->gb);
-
- // The pixels are stored in the same order as levels in h->mb array.
- for(x=0; x < mb_size; x++){
- ((uint8_t*)h->mb)[x]= get_bits(&s->gb, 8);
- }
+ h->intra_pcm_ptr = align_get_bits(&s->gb);
+ skip_bits_long(&s->gb, mb_size);
// In deblocking, the quantizer is 0
s->current_picture.f.qscale_table[mb_xy] = 0;
diff --git a/libavcodec/h264_mb_template.c b/libavcodec/h264_mb_template.c
index 0f0e451..eac5d1b 100644
--- a/libavcodec/h264_mb_template.c
+++ b/libavcodec/h264_mb_template.c
@@ -103,7 +103,7 @@ static av_noinline void FUNC(hl_decode_mb)(H264Context *h)
if (PIXEL_SHIFT) {
int j;
GetBitContext gb;
- init_get_bits(&gb, (uint8_t *)h->mb,
+ init_get_bits(&gb, (uint8_t *)h->intra_pcm_ptr,
ff_h264_mb_sizes[h->sps.chroma_format_idc] * bit_depth);
for (i = 0; i < 16; i++) {
@@ -135,7 +135,7 @@ static av_noinline void FUNC(hl_decode_mb)(H264Context *h)
}
} else {
for (i = 0; i < 16; i++)
- memcpy(dest_y + i * linesize, (uint8_t *)h->mb + i * 16, 16);
+ memcpy(dest_y + i * linesize, (uint8_t *)h->intra_pcm_ptr + i * 16, 16);
if (SIMPLE || !CONFIG_GRAY || !(s->flags & CODEC_FLAG_GRAY)) {
if (!h->sps.chroma_format_idc) {
for (i = 0; i < 8; i++) {
@@ -143,8 +143,8 @@ static av_noinline void FUNC(hl_decode_mb)(H264Context *h)
memset(dest_cr + i*uvlinesize, 1 << (bit_depth - 1), 8);
}
} else {
- uint8_t *src_cb = (uint8_t *)h->mb + 256;
- uint8_t *src_cr = (uint8_t *)h->mb + 256 + block_h * 8;
+ uint8_t *src_cb = (uint8_t *)h->intra_pcm_ptr + 256;
+ uint8_t *src_cr = (uint8_t *)h->intra_pcm_ptr + 256 + block_h * 8;
for (i = 0; i < block_h; i++) {
memcpy(dest_cb + i * uvlinesize, src_cb + i * 8, 8);
memcpy(dest_cr + i * uvlinesize, src_cr + i * 8, 8);
@@ -259,10 +259,10 @@ static av_noinline void FUNC(hl_decode_mb)(H264Context *h)
}
}
}
- }
- if (h->cbp || IS_INTRA(mb_type)) {
- s->dsp.clear_blocks(h->mb);
- s->dsp.clear_blocks(h->mb + (24 * 16 << PIXEL_SHIFT));
+ if (h->cbp || IS_INTRA(mb_type)) {
+ s->dsp.clear_blocks(h->mb);
+ s->dsp.clear_blocks(h->mb + (24 * 16 << PIXEL_SHIFT));
+ }
}
}
@@ -327,7 +327,7 @@ static av_noinline void FUNC(hl_decode_mb_444)(H264Context *h)
if (PIXEL_SHIFT) {
const int bit_depth = h->sps.bit_depth_luma;
GetBitContext gb;
- init_get_bits(&gb, (uint8_t *)h->mb, 768 * bit_depth);
+ init_get_bits(&gb, (uint8_t *)h->intra_pcm_ptr, 768 * bit_depth);
for (p = 0; p < plane_count; p++)
for (i = 0; i < 16; i++) {
@@ -339,7 +339,7 @@ static av_noinline void FUNC(hl_decode_mb_444)(H264Context *h)
for (p = 0; p < plane_count; p++)
for (i = 0; i < 16; i++)
memcpy(dest[p] + i * linesize,
- (uint8_t *)h->mb + p * 256 + i * 16, 16);
+ (uint8_t *)h->intra_pcm_ptr + p * 256 + i * 16, 16);
}
} else {
if (IS_INTRA(mb_type)) {
@@ -367,10 +367,11 @@ static av_noinline void FUNC(hl_decode_mb_444)(H264Context *h)
hl_decode_mb_idct_luma(h, mb_type, 1, SIMPLE, transform_bypass,
PIXEL_SHIFT, block_offset, linesize,
dest[p], p);
- }
- if (h->cbp || IS_INTRA(mb_type)) {
- s->dsp.clear_blocks(h->mb);
- s->dsp.clear_blocks(h->mb + (24 * 16 << PIXEL_SHIFT));
+
+ if (h->cbp || IS_INTRA(mb_type)) {
+ s->dsp.clear_blocks(h->mb);
+ s->dsp.clear_blocks(h->mb + (24 * 16 << PIXEL_SHIFT));
+ }
}
}
--
1.7.11.3
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