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Add prefetching to VP8 decoder

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~5% faster overall, probably depends on CPU and resolution.

Originally committed as revision 24410 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Jason Garrett-Glaser 2010-07-22 03:09:10 +00:00
parent 003243c3c2
commit d864dee8ab
1 changed files with 23 additions and 0 deletions
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23
libavcodec/vp8.c
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@ -1054,6 +1054,21 @@ static inline void vp8_mc_part(VP8Context *s, uint8_t *dst[3],
s->put_pixels_tab[1 + (block_w == 4)]);
}
/* Fetch pixels for estimated mv 4 macroblocks ahead.
* Optimized for 64-byte cache lines. Inspired by ffh264 prefetch_motion. */
static inline void prefetch_motion(VP8Context *s, VP8Macroblock *mb, int mb_x, int mb_y, int x_off, int y_off, int ref)
{
if (mb->ref_frame != VP56_FRAME_CURRENT) {
int mx = mb->mv.x + x_off + 8;
int my = mb->mv.y + y_off;
uint8_t **src= s->framep[mb->ref_frame]->data;
int off= mx + (my + (mb_x&3)*4)*s->linesize + 64;
s->dsp.prefetch(src[0]+off, s->linesize, 4);
off= (mx>>1) + ((my>>1) + (mb_x&7))*s->uvlinesize + 64;
s->dsp.prefetch(src[1]+off, src[2]-src[1], 2);
}
}
/**
* Apply motion vectors to prediction buffer, chapter 18.
*/
@ -1063,6 +1078,8 @@ static void inter_predict(VP8Context *s, uint8_t *dst[3], VP8Macroblock *mb,
int x_off = mb_x << 4, y_off = mb_y << 4;
int width = 16*s->mb_width, height = 16*s->mb_height;
prefetch_motion(s, mb, mb_x, mb_y, x_off, y_off, VP56_FRAME_PREVIOUS);
if (mb->mode < VP8_MVMODE_SPLIT) {
vp8_mc_part(s, dst, s->framep[mb->ref_frame], x_off, y_off,
0, 0, 16, 16, width, height, &mb->mv);
@ -1137,6 +1154,8 @@ static void inter_predict(VP8Context *s, uint8_t *dst[3], VP8Macroblock *mb,
8, 8, 8, 8, width, height, &mb->bmv[3]);
break;
}
prefetch_motion(s, mb, mb_x, mb_y, x_off, y_off, VP56_FRAME_GOLDEN);
}
static void idct_mb(VP8Context *s, uint8_t *y_dst, uint8_t *u_dst, uint8_t *v_dst,
@ -1431,6 +1450,10 @@ static int vp8_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
memset(s->top_border, 129, sizeof(*s->top_border));
for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
/* Prefetch the current frame, 4 MBs ahead */
s->dsp.prefetch(dst[0] + (mb_x&3)*4*s->linesize + 64, s->linesize, 4);
s->dsp.prefetch(dst[1] + (mb_x&7)*s->uvlinesize + 64, dst[2] - dst[1], 2);
decode_mb_mode(s, mb, mb_x, mb_y, intra4x4 + 4*mb_x);
if (!mb->skip)