From dc60061bb6e3b2ee87a12fb3a26239d7b5a74379 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Fri, 31 May 2013 15:39:22 +0200 Subject: [PATCH] jpeg2000dec: optimize dequantization_int() 4400->2800 cycles Signed-off-by: Michael Niedermayer --- libavcodec/jpeg2000dec.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/libavcodec/jpeg2000dec.c b/libavcodec/jpeg2000dec.c index 3b035b88c3..9822900b02 100644 --- a/libavcodec/jpeg2000dec.c +++ b/libavcodec/jpeg2000dec.c @@ -938,14 +938,14 @@ 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.