avcodec/jpeg2000dwt: merge rescaling with interleave in 9/7 float IDWT

10% faster

Reviewed-by: Nicolas BERTRAND <nicoinattendu@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2013-06-02 22:18:29 +02:00
parent 6507d86f07
commit 96b71a6ec5

View File

@ -359,13 +359,6 @@ static void sr_1d97_float(float *p, int i0, int i1)
extend97_float(p, i0, i1);
/*step 1*/
for (i = i0 / 2 - 1; i < i1 / 2 + 2; i++)
p[2 * i] *= F_LFTG_K;
/* step 2*/
for (i = i0 / 2 - 2; i < i1 / 2 + 2; i++)
p[2 * i + 1] *= F_LFTG_X;
/* step 3*/
for (i = i0 / 2 - 1; i < i1 / 2 + 2; i++)
p[2 * i] -= F_LFTG_DELTA * (p[2 * i - 1] + p[2 * i + 1]);
/* step 4 */
@ -401,9 +394,9 @@ static void dwt_decode97_float(DWTContext *s, float *t)
int i, j = 0;
// copy with interleaving
for (i = mh; i < lh; i += 2, j++)
l[i] = data[w * lp + j];
l[i] = data[w * lp + j] * F_LFTG_K;
for (i = 1 - mh; i < lh; i += 2, j++)
l[i] = data[w * lp + j];
l[i] = data[w * lp + j] * F_LFTG_X;
sr_1d97_float(line, mh, mh + lh);
@ -417,9 +410,9 @@ static void dwt_decode97_float(DWTContext *s, float *t)
int i, j = 0;
// copy with interleaving
for (i = mv; i < lv; i += 2, j++)
l[i] = data[w * j + lp];
l[i] = data[w * j + lp] * F_LFTG_K;
for (i = 1 - mv; i < lv; i += 2, j++)
l[i] = data[w * j + lp];
l[i] = data[w * j + lp] * F_LFTG_X;
sr_1d97_float(line, mv, mv + lv);