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| author | Michael Niedermayer <michaelni@gmx.at> | 2013-05-31 15:36:49 +0200 |
|---|---|---|
| committer | Michael Niedermayer <michaelni@gmx.at> | 2013-06-01 11:48:09 +0200 |
| commit | 6cbd0241f216d74ac46c3ab73a36f6e341aa39e6 (patch) | |
| tree | 5f7ad6e00a2b9dbbd3468740b565ad274b155dff | |
| parent | c485c835fef46dea5dddf66243954275291dcdee (diff) | |
| download | ffmpeg-6cbd0241f216d74ac46c3ab73a36f6e341aa39e6.tar.gz | |
jpeg2000dec: optimize dequantization_float()
4700 -> 2700 cycles (sandybridge i7)
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
| -rw-r--r-- | libavcodec/jpeg2000dec.c | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/libavcodec/jpeg2000dec.c b/libavcodec/jpeg2000dec.c index e2540a6c82..3b035b88c3 100644 --- a/libavcodec/jpeg2000dec.c +++ b/libavcodec/jpeg2000dec.c @@ -923,13 +923,14 @@ static void dequantization_float(int x, int y, Jpeg2000Cblk *cblk, Jpeg2000Component *comp, Jpeg2000T1Context *t1, Jpeg2000Band *band) { - int i, j, idx; - float *datap = &comp->f_data[(comp->coord[0][1] - comp->coord[0][0]) * y + x]; - for (j = 0; j < (cblk->coord[1][1] - cblk->coord[1][0]); ++j) - for (i = 0; i < (cblk->coord[0][1] - cblk->coord[0][0]); ++i) { - idx = (comp->coord[0][1] - comp->coord[0][0]) * j + i; - datap[idx] = (float)(t1->data[j][i]) * band->f_stepsize; - } + int i, j; + int w = cblk->coord[0][1] - cblk->coord[0][0]; + for (j = 0; j < (cblk->coord[1][1] - cblk->coord[1][0]); ++j) { + float *datap = &comp->f_data[(comp->coord[0][1] - comp->coord[0][0]) * (y + j) + x]; + int *src = t1->data[j]; + for (i = 0; i < w; ++i) + datap[i] = src[i] * band->f_stepsize; + } } /* Integer dequantization of a codeblock.*/ |