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 */
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);
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);
extend97_int(p, i0, i1);
- /*step 1*/
- for (i = i0 / 2 - 1; i < i1 / 2 + 2; i++)
- p[2 * i] = ((p[2 * i] * I_LFTG_K) + (1 << 15)) >> 16;
- /* step 2*/
- for (i = i0 / 2 - 2; i < i1 / 2 + 2; i++)
- p[2 * i + 1] = ((p[2 * i + 1] * I_LFTG_X) + (1 << 15)) >> 16;
- /* step 3*/
for (i = i0 / 2 - 1; i < i1 / 2 + 2; i++)
p[2 * i] -= (I_LFTG_DELTA * (p[2 * i - 1] + p[2 * i + 1]) + (1 << 15)) >> 16;
/* step 4 */
l = line + mh;
for (lp = 0; lp < lv; lp++) {
int i, j = 0;
- // copy with interleaving
+ // rescale with interleaving
for (i = mh; i < lh; i += 2, j++)
- l[i] = data[w * lp + j];
+ l[i] = ((data[w * lp + j] * I_LFTG_K) + (1 << 15)) >> 16;
for (i = 1 - mh; i < lh; i += 2, j++)
- l[i] = data[w * lp + j];
+ l[i] = ((data[w * lp + j] * I_LFTG_X) + (1 << 15)) >> 16;
sr_1d97_int(line, mh, mh + lh);
l = line + mv;
for (lp = 0; lp < lh; lp++) {
int i, j = 0;
- // copy with interleaving
+ // rescale with interleaving
for (i = mv; i < lv; i += 2, j++)
- l[i] = data[w * j + lp];
+ l[i] = ((data[w * j + lp] * I_LFTG_K) + (1 << 15)) >> 16;
for (i = 1 - mv; i < lv; i += 2, j++)
- l[i] = data[w * j + lp];
+ l[i] = ((data[w * j + lp] * I_LFTG_X) + (1 << 15)) >> 16;
sr_1d97_int(line, mv, mv + lv);