jpeg2000dec: optimize dequantization_int()

4400->2800 cycles

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2013-05-31 15:39:22 +02:00
parent 6cbd0241f2
commit dc60061bb6

View File

@ -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.