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| author | Michael Niedermayer <michael@niedermayer.cc> | 2018-08-05 16:13:24 +0200 |
|---|---|---|
| committer | Michael Niedermayer <michael@niedermayer.cc> | 2018-09-28 01:25:17 +0200 |
| commit | b90d8cc7466386a166dd72107457498aa5a7c43d (patch) | |
| tree | 9a782ad4e15e93316e89b03f7779d5e97a7c5873 | |
| parent | 303439bc5f7ac6bbadc20d7ec2d7ee4fec656ead (diff) | |
| download | ffmpeg-b90d8cc7466386a166dd72107457498aa5a7c43d.tar.gz | |
avcodec/gdv: Replace divisions by shifts in rescale()
Divisions tend to be slower than shifts unless the compiler optimizes them out.
And some of these are in inner loops.
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
| -rw-r--r-- | libavcodec/gdv.c | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/libavcodec/gdv.c b/libavcodec/gdv.c index e52a637610..79ca157dde 100644 --- a/libavcodec/gdv.c +++ b/libavcodec/gdv.c @@ -85,14 +85,14 @@ static void rescale(GDVContext *gdv, uint8_t *dst, int w, int h, int scale_v, in int y = h - j - 1; for (i = 0; i < w; i++) { int x = w - i - 1; - dst[PREAMBLE_SIZE + x + y * w] = dst[PREAMBLE_SIZE + x/2 + (y/2) * (w/2)]; + dst[PREAMBLE_SIZE + x + y * w] = dst[PREAMBLE_SIZE + (x>>1) + (y>>1) * (w>>1)]; } } } else if (gdv->scale_h) { for (j = 0; j < h; j++) { int y = h - j - 1; for (x = 0; x < w; x++) { - dst[PREAMBLE_SIZE + x + y * w] = dst[PREAMBLE_SIZE + x + (y/2) * w]; + dst[PREAMBLE_SIZE + x + y * w] = dst[PREAMBLE_SIZE + x + (y>>1) * w]; } } } else if (gdv->scale_v) { @@ -100,26 +100,26 @@ static void rescale(GDVContext *gdv, uint8_t *dst, int w, int h, int scale_v, in int y = h - j - 1; for (i = 0; i < w; i++) { int x = w - i - 1; - dst[PREAMBLE_SIZE + x + y * w] = dst[PREAMBLE_SIZE + x/2 + y * (w/2)]; + dst[PREAMBLE_SIZE + x + y * w] = dst[PREAMBLE_SIZE + (x>>1) + y * (w>>1)]; } } } if (scale_h && scale_v) { - for (y = 0; y < h/2; y++) { - for (x = 0; x < w/2; x++) { - dst[PREAMBLE_SIZE + x + y * (w/2)] = dst[PREAMBLE_SIZE + x*2 + y*2 * w]; + for (y = 0; y < (h>>1); y++) { + for (x = 0; x < (w>>1); x++) { + dst[PREAMBLE_SIZE + x + y * (w>>1)] = dst[PREAMBLE_SIZE + x*2 + y*2 * w]; } } } else if (scale_h) { - for (y = 0; y < h/2; y++) { + for (y = 0; y < (h>>1); y++) { for (x = 0; x < w; x++) { dst[PREAMBLE_SIZE + x + y * w] = dst[PREAMBLE_SIZE + x + y*2 * w]; } } } else if (scale_v) { for (y = 0; y < h; y++) { - for (x = 0; x < w/2; x++) { + for (x = 0; x < (w>>1); x++) { dst[PREAMBLE_SIZE + x + y * w] = dst[PREAMBLE_SIZE + x*2 + y * w]; } } |