Skip to content

F
ffmpeg.wasm-core
Commit c4604b87 authored by Michael Niedermayer's avatar Michael Niedermayer Committed by Luca Barbato
Browse files
Options

jpeg2000: Merge rescaling with interleaving in 9/7 IDWT 

Signed-off-by: 's avatarLuca Barbato <lu_zero@gentoo.org>
parent 22e18ea3
Show whitespace changes
Inline Side-by-side
Showing with 10 additions and 24 deletions
libavcodec/jpeg2000dwt.c
View file @ c4604b87
......@@ -153,13 +153,6 @@ 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 */
......@@ -195,9 +188,9 @@ 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);
......@@ -211,9 +204,9 @@ 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);
......@@ -232,13 +225,6 @@ static void sr_1d97_int(int32_t *p, int i0, int i1)
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 */
......@@ -272,11 +258,11 @@ static void dwt_decode97_int(DWTContext *s, int32_t *t)
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);
......@@ -288,11 +274,11 @@ static void dwt_decode97_int(DWTContext *s, int32_t *t)
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);
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment