[FFmpeg-cvslog] dnxhddec: optimise dnxhd_decode_dct_block()
Mans Rullgard
git at videolan.org
Fri Jul 22 12:16:59 CEST 2011
ffmpeg | branch: master | Mans Rullgard <mans at mansr.com> | Thu Jul 21 19:04:37 2011 +0100| [bb32fded3623a20ff8999c2924315841c08c985c] | committer: Mans Rullgard
dnxhddec: optimise dnxhd_decode_dct_block()
Template the function for 8/10-bit and use lowlevel bitstream
macros.
6% faster overall on i7 gcc 4.5.
Signed-off-by: Mans Rullgard <mans at mansr.com>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=bb32fded3623a20ff8999c2924315841c08c985c
---
libavcodec/dnxhddec.c | 104 +++++++++++++++++++++++++++++++-----------------
1 files changed, 67 insertions(+), 37 deletions(-)
diff --git a/libavcodec/dnxhddec.c b/libavcodec/dnxhddec.c
index 7b32cd3..426be2e 100644
--- a/libavcodec/dnxhddec.c
+++ b/libavcodec/dnxhddec.c
@@ -31,7 +31,7 @@
#include "dnxhddata.h"
#include "dsputil.h"
-typedef struct {
+typedef struct DNXHDContext {
AVCodecContext *avctx;
AVFrame picture;
GetBitContext gb;
@@ -47,11 +47,16 @@ typedef struct {
ScanTable scantable;
const CIDEntry *cid_table;
int bit_depth; // 8, 10 or 0 if not initialized at all.
+ void (*decode_dct_block)(struct DNXHDContext *ctx, DCTELEM *block,
+ int n, int qscale);
} DNXHDContext;
#define DNXHD_VLC_BITS 9
#define DNXHD_DC_VLC_BITS 7
+static void dnxhd_decode_dct_block_8(DNXHDContext *ctx, DCTELEM *block, int n, int qscale);
+static void dnxhd_decode_dct_block_10(DNXHDContext *ctx, DCTELEM *block, int n, int qscale);
+
static av_cold int dnxhd_decode_init(AVCodecContext *avctx)
{
DNXHDContext *ctx = avctx->priv_data;
@@ -118,6 +123,7 @@ static int dnxhd_decode_header(DNXHDContext *ctx, const uint8_t *buf, int buf_si
if (ctx->bit_depth != 10) {
dsputil_init(&ctx->dsp, ctx->avctx);
ctx->bit_depth = 10;
+ ctx->decode_dct_block = dnxhd_decode_dct_block_10;
}
} else {
ctx->avctx->pix_fmt = PIX_FMT_YUV422P;
@@ -125,6 +131,7 @@ static int dnxhd_decode_header(DNXHDContext *ctx, const uint8_t *buf, int buf_si
if (ctx->bit_depth != 8) {
dsputil_init(&ctx->dsp, ctx->avctx);
ctx->bit_depth = 8;
+ ctx->decode_dct_block = dnxhd_decode_dct_block_8;
}
}
@@ -165,71 +172,94 @@ static int dnxhd_decode_header(DNXHDContext *ctx, const uint8_t *buf, int buf_si
return 0;
}
-static int dnxhd_decode_dc(DNXHDContext *ctx)
-{
- int len;
-
- len = get_vlc2(&ctx->gb, ctx->dc_vlc.table, DNXHD_DC_VLC_BITS, 1);
- return len ? get_xbits(&ctx->gb, len) : 0;
-}
-
-static void dnxhd_decode_dct_block(DNXHDContext *ctx, DCTELEM *block, int n, int qscale)
+static av_always_inline void dnxhd_decode_dct_block(DNXHDContext *ctx,
+ DCTELEM *block, int n,
+ int qscale,
+ int index_bits,
+ int level_bias,
+ int level_shift)
{
- int i, j, index, index2;
+ int i, j, index1, index2, len;
int level, component, sign;
- const uint8_t *weigth_matrix;
+ const uint8_t *weight_matrix;
+ OPEN_READER(bs, &ctx->gb);
if (n&2) {
component = 1 + (n&1);
- weigth_matrix = ctx->cid_table->chroma_weight;
+ weight_matrix = ctx->cid_table->chroma_weight;
} else {
component = 0;
- weigth_matrix = ctx->cid_table->luma_weight;
+ weight_matrix = ctx->cid_table->luma_weight;
}
- ctx->last_dc[component] += dnxhd_decode_dc(ctx);
+ UPDATE_CACHE(bs, &ctx->gb);
+ GET_VLC(len, bs, &ctx->gb, ctx->dc_vlc.table, DNXHD_DC_VLC_BITS, 1);
+ if (len) {
+ level = GET_CACHE(bs, &ctx->gb);
+ LAST_SKIP_BITS(bs, &ctx->gb, len);
+ sign = ~level >> 31;
+ level = (NEG_USR32(sign ^ level, len) ^ sign) - sign;
+ ctx->last_dc[component] += level;
+ }
block[0] = ctx->last_dc[component];
//av_log(ctx->avctx, AV_LOG_DEBUG, "dc %d\n", block[0]);
+
for (i = 1; ; i++) {
- index = get_vlc2(&ctx->gb, ctx->ac_vlc.table, DNXHD_VLC_BITS, 2);
- //av_log(ctx->avctx, AV_LOG_DEBUG, "index %d\n", index);
- level = ctx->cid_table->ac_level[index];
+ UPDATE_CACHE(bs, &ctx->gb);
+ GET_VLC(index1, bs, &ctx->gb, ctx->ac_vlc.table,
+ DNXHD_VLC_BITS, 2);
+ //av_log(ctx->avctx, AV_LOG_DEBUG, "index %d\n", index1);
+ level = ctx->cid_table->ac_level[index1];
if (!level) { /* EOB */
//av_log(ctx->avctx, AV_LOG_DEBUG, "EOB\n");
- return;
+ break;
}
- sign = get_sbits(&ctx->gb, 1);
- if (ctx->cid_table->ac_index_flag[index]) {
- level += get_bits(&ctx->gb, ctx->cid_table->index_bits)<<6;
+ sign = SHOW_SBITS(bs, &ctx->gb, 1);
+ SKIP_BITS(bs, &ctx->gb, 1);
+
+ if (ctx->cid_table->ac_index_flag[index1]) {
+ level += SHOW_UBITS(bs, &ctx->gb, index_bits) << 6;
+ SKIP_BITS(bs, &ctx->gb, index_bits);
}
- if (ctx->cid_table->ac_run_flag[index]) {
- index2 = get_vlc2(&ctx->gb, ctx->run_vlc.table, DNXHD_VLC_BITS, 2);
+ if (ctx->cid_table->ac_run_flag[index1]) {
+ UPDATE_CACHE(bs, &ctx->gb);
+ GET_VLC(index2, bs, &ctx->gb, ctx->run_vlc.table,
+ DNXHD_VLC_BITS, 2);
i += ctx->cid_table->run[index2];
}
if (i > 63) {
av_log(ctx->avctx, AV_LOG_ERROR, "ac tex damaged %d, %d\n", n, i);
- return;
+ break;
}
j = ctx->scantable.permutated[i];
//av_log(ctx->avctx, AV_LOG_DEBUG, "j %d\n", j);
- //av_log(ctx->avctx, AV_LOG_DEBUG, "level %d, weigth %d\n", level, weigth_matrix[i]);
- level = (2*level+1) * qscale * weigth_matrix[i];
- if (ctx->bit_depth == 10) {
- if (weigth_matrix[i] != 8)
- level += 8;
- level >>= 4;
- } else {
- if (weigth_matrix[i] != 32)
- level += 32;
- level >>= 6;
- }
+ //av_log(ctx->avctx, AV_LOG_DEBUG, "level %d, weight %d\n", level, weight_matrix[i]);
+ level = (2*level+1) * qscale * weight_matrix[i];
+ if (weight_matrix[i] != level_bias)
+ level += level_bias;
+ level >>= level_shift;
+
//av_log(NULL, AV_LOG_DEBUG, "i %d, j %d, end level %d\n", i, j, level);
block[j] = (level^sign) - sign;
}
+
+ CLOSE_READER(bs, &ctx->gb);
+}
+
+static void dnxhd_decode_dct_block_8(DNXHDContext *ctx, DCTELEM *block,
+ int n, int qscale)
+{
+ dnxhd_decode_dct_block(ctx, block, n, qscale, 4, 32, 6);
+}
+
+static void dnxhd_decode_dct_block_10(DNXHDContext *ctx, DCTELEM *block,
+ int n, int qscale)
+{
+ dnxhd_decode_dct_block(ctx, block, n, qscale, 6, 8, 4);
}
static int dnxhd_decode_macroblock(DNXHDContext *ctx, int x, int y)
@@ -247,7 +277,7 @@ static int dnxhd_decode_macroblock(DNXHDContext *ctx, int x, int y)
for (i = 0; i < 8; i++) {
ctx->dsp.clear_block(ctx->blocks[i]);
- dnxhd_decode_dct_block(ctx, ctx->blocks[i], i, qscale);
+ ctx->decode_dct_block(ctx, ctx->blocks[i], i, qscale);
}
if (ctx->picture.interlaced_frame) {
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