From e11099db203c46ddeb9ac5707a824c8ae01ee8f4 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Mon, 1 Jul 2013 10:01:35 +0200 Subject: jpeg2000: Optimize dequantization Float: 4700 -> 2700 cycles Integer: 4400 -> 2800 cycles (sandybridge i7) Signed-off-by: Luca Barbato --- libavcodec/jpeg2000dec.c | 31 ++++++++++++++++--------------- 1 file changed, 16 insertions(+), 15 deletions(-) (limited to 'libavcodec') diff --git a/libavcodec/jpeg2000dec.c b/libavcodec/jpeg2000dec.c index d2974be432..589cbc12b1 100644 --- a/libavcodec/jpeg2000dec.c +++ b/libavcodec/jpeg2000dec.c @@ -1006,13 +1006,14 @@ 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.*/ @@ -1020,14 +1021,14 @@ static void dequantization_int(int x, int y, Jpeg2000Cblk *cblk, Jpeg2000Component *comp, Jpeg2000T1Context *t1, Jpeg2000Band *band) { - int i, j, idx; - int32_t *datap = &comp->i_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] = - ((int32_t)(t1->data[j][i]) * band->i_stepsize + (1 << 15)) >> 16; - } + 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) { + int32_t *datap = &comp->i_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->i_stepsize + (1 << 15)) >> 16; + } } /* Inverse ICT parameters in float and integer. -- cgit v1.2.3