-
-
Notifications
You must be signed in to change notification settings - Fork 5.4k
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Browse files
Browse the repository at this point in the history
- Loading branch information
Showing
29 changed files
with
6,001 additions
and
0 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,225 @@ | ||
/* | ||
* (I)DCT Transforms | ||
* Copyright (c) 2009 Peter Ross <pross@xvid.org> | ||
* Copyright (c) 2010 Alex Converse <alex.converse@gmail.com> | ||
* Copyright (c) 2010 Vitor Sessak | ||
* | ||
* This file is part of FFmpeg. | ||
* | ||
* FFmpeg is free software; you can redistribute it and/or | ||
* modify it under the terms of the GNU Lesser General Public | ||
* License as published by the Free Software Foundation; either | ||
* version 2.1 of the License, or (at your option) any later version. | ||
* | ||
* FFmpeg is distributed in the hope that it will be useful, | ||
* but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
* Lesser General Public License for more details. | ||
* | ||
* You should have received a copy of the GNU Lesser General Public | ||
* License along with FFmpeg; if not, write to the Free Software | ||
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | ||
*/ | ||
|
||
/** | ||
* @file | ||
* (Inverse) Discrete Cosine Transforms. These are also known as the | ||
* type II and type III DCTs respectively. | ||
*/ | ||
|
||
#include <math.h> | ||
#include <string.h> | ||
|
||
#include "libavutil/mathematics.h" | ||
#include "dct.h" | ||
#include "dct32.h" | ||
|
||
/* sin((M_PI * x / (2 * n)) */ | ||
#define SIN(s, n, x) (s->costab[(n) - (x)]) | ||
|
||
/* cos((M_PI * x / (2 * n)) */ | ||
#define COS(s, n, x) (s->costab[x]) | ||
|
||
static void dst_calc_I_c(DCTContext *ctx, FFTSample *data) | ||
{ | ||
int n = 1 << ctx->nbits; | ||
int i; | ||
|
||
data[0] = 0; | ||
for (i = 1; i < n / 2; i++) { | ||
float tmp1 = data[i ]; | ||
float tmp2 = data[n - i]; | ||
float s = SIN(ctx, n, 2 * i); | ||
|
||
s *= tmp1 + tmp2; | ||
tmp1 = (tmp1 - tmp2) * 0.5f; | ||
data[i] = s + tmp1; | ||
data[n - i] = s - tmp1; | ||
} | ||
|
||
data[n / 2] *= 2; | ||
ctx->rdft.rdft_calc(&ctx->rdft, data); | ||
|
||
data[0] *= 0.5f; | ||
|
||
for (i = 1; i < n - 2; i += 2) { | ||
data[i + 1] += data[i - 1]; | ||
data[i] = -data[i + 2]; | ||
} | ||
|
||
data[n - 1] = 0; | ||
} | ||
|
||
static void dct_calc_I_c(DCTContext *ctx, FFTSample *data) | ||
{ | ||
int n = 1 << ctx->nbits; | ||
int i; | ||
float next = -0.5f * (data[0] - data[n]); | ||
|
||
for (i = 0; i < n / 2; i++) { | ||
float tmp1 = data[i]; | ||
float tmp2 = data[n - i]; | ||
float s = SIN(ctx, n, 2 * i); | ||
float c = COS(ctx, n, 2 * i); | ||
|
||
c *= tmp1 - tmp2; | ||
s *= tmp1 - tmp2; | ||
|
||
next += c; | ||
|
||
tmp1 = (tmp1 + tmp2) * 0.5f; | ||
data[i] = tmp1 - s; | ||
data[n - i] = tmp1 + s; | ||
} | ||
|
||
ctx->rdft.rdft_calc(&ctx->rdft, data); | ||
data[n] = data[1]; | ||
data[1] = next; | ||
|
||
for (i = 3; i <= n; i += 2) | ||
data[i] = data[i - 2] - data[i]; | ||
} | ||
|
||
static void dct_calc_III_c(DCTContext *ctx, FFTSample *data) | ||
{ | ||
int n = 1 << ctx->nbits; | ||
int i; | ||
|
||
float next = data[n - 1]; | ||
float inv_n = 1.0f / n; | ||
|
||
for (i = n - 2; i >= 2; i -= 2) { | ||
float val1 = data[i]; | ||
float val2 = data[i - 1] - data[i + 1]; | ||
float c = COS(ctx, n, i); | ||
float s = SIN(ctx, n, i); | ||
|
||
data[i] = c * val1 + s * val2; | ||
data[i + 1] = s * val1 - c * val2; | ||
} | ||
|
||
data[1] = 2 * next; | ||
|
||
ctx->rdft.rdft_calc(&ctx->rdft, data); | ||
|
||
for (i = 0; i < n / 2; i++) { | ||
float tmp1 = data[i] * inv_n; | ||
float tmp2 = data[n - i - 1] * inv_n; | ||
float csc = ctx->csc2[i] * (tmp1 - tmp2); | ||
|
||
tmp1 += tmp2; | ||
data[i] = tmp1 + csc; | ||
data[n - i - 1] = tmp1 - csc; | ||
} | ||
} | ||
|
||
static void dct_calc_II_c(DCTContext *ctx, FFTSample *data) | ||
{ | ||
int n = 1 << ctx->nbits; | ||
int i; | ||
float next; | ||
|
||
for (i = 0; i < n / 2; i++) { | ||
float tmp1 = data[i]; | ||
float tmp2 = data[n - i - 1]; | ||
float s = SIN(ctx, n, 2 * i + 1); | ||
|
||
s *= tmp1 - tmp2; | ||
tmp1 = (tmp1 + tmp2) * 0.5f; | ||
|
||
data[i] = tmp1 + s; | ||
data[n-i-1] = tmp1 - s; | ||
} | ||
|
||
ctx->rdft.rdft_calc(&ctx->rdft, data); | ||
|
||
next = data[1] * 0.5; | ||
data[1] *= -1; | ||
|
||
for (i = n - 2; i >= 0; i -= 2) { | ||
float inr = data[i ]; | ||
float ini = data[i + 1]; | ||
float c = COS(ctx, n, i); | ||
float s = SIN(ctx, n, i); | ||
|
||
data[i] = c * inr + s * ini; | ||
data[i + 1] = next; | ||
|
||
next += s * inr - c * ini; | ||
} | ||
} | ||
|
||
static void dct32_func(DCTContext *ctx, FFTSample *data) | ||
{ | ||
ctx->dct32(data, data); | ||
} | ||
|
||
av_cold int ff_dct_init(DCTContext *s, int nbits, enum DCTTransformType inverse) | ||
{ | ||
int n = 1 << nbits; | ||
int i; | ||
int ret; | ||
|
||
memset(s, 0, sizeof(*s)); | ||
|
||
s->nbits = nbits; | ||
s->inverse = inverse; | ||
|
||
if (inverse == DCT_II && nbits == 5) { | ||
s->dct_calc = dct32_func; | ||
} else { | ||
ff_init_ff_cos_tabs(nbits + 2); | ||
|
||
s->costab = ff_cos_tabs[nbits + 2]; | ||
s->csc2 = av_malloc_array(n / 2, sizeof(FFTSample)); | ||
if (!s->csc2) | ||
return AVERROR(ENOMEM); | ||
|
||
if ((ret = ff_rdft_init(&s->rdft, nbits, inverse == DCT_III)) < 0) { | ||
av_freep(&s->csc2); | ||
return ret; | ||
} | ||
|
||
for (i = 0; i < n / 2; i++) | ||
s->csc2[i] = 0.5 / sin((M_PI / (2 * n) * (2 * i + 1))); | ||
|
||
switch (inverse) { | ||
case DCT_I : s->dct_calc = dct_calc_I_c; break; | ||
case DCT_II : s->dct_calc = dct_calc_II_c; break; | ||
case DCT_III: s->dct_calc = dct_calc_III_c; break; | ||
case DST_I : s->dct_calc = dst_calc_I_c; break; | ||
} | ||
} | ||
|
||
s->dct32 = ff_dct32_float; | ||
if (ARCH_X86) | ||
ff_dct_init_x86(s); | ||
|
||
return 0; | ||
} | ||
|
||
av_cold void ff_dct_end(DCTContext *s) | ||
{ | ||
ff_rdft_end(&s->rdft); | ||
av_freep(&s->csc2); | ||
} |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,25 @@ | ||
/* | ||
* This file is part of FFmpeg. | ||
* | ||
* FFmpeg is free software; you can redistribute it and/or | ||
* modify it under the terms of the GNU Lesser General Public | ||
* License as published by the Free Software Foundation; either | ||
* version 2.1 of the License, or (at your option) any later version. | ||
* | ||
* FFmpeg is distributed in the hope that it will be useful, | ||
* but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
* Lesser General Public License for more details. | ||
* | ||
* You should have received a copy of the GNU Lesser General Public | ||
* License along with FFmpeg; if not, write to the Free Software | ||
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | ||
*/ | ||
|
||
#ifndef AVCODEC_DCT32_H | ||
#define AVCODEC_DCT32_H | ||
|
||
void ff_dct32_float(float *dst, const float *src); | ||
void ff_dct32_fixed(int *dst, const int *src); | ||
|
||
#endif /* AVCODEC_DCT32_H */ |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,20 @@ | ||
/* | ||
* This file is part of FFmpeg. | ||
* | ||
* FFmpeg is free software; you can redistribute it and/or | ||
* modify it under the terms of the GNU Lesser General Public | ||
* License as published by the Free Software Foundation; either | ||
* version 2.1 of the License, or (at your option) any later version. | ||
* | ||
* FFmpeg is distributed in the hope that it will be useful, | ||
* but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
* Lesser General Public License for more details. | ||
* | ||
* You should have received a copy of the GNU Lesser General Public | ||
* License along with FFmpeg; if not, write to the Free Software | ||
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | ||
*/ | ||
|
||
#define DCT32_FLOAT 0 | ||
#include "dct32_template.c" |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,20 @@ | ||
/* | ||
* This file is part of FFmpeg. | ||
* | ||
* FFmpeg is free software; you can redistribute it and/or | ||
* modify it under the terms of the GNU Lesser General Public | ||
* License as published by the Free Software Foundation; either | ||
* version 2.1 of the License, or (at your option) any later version. | ||
* | ||
* FFmpeg is distributed in the hope that it will be useful, | ||
* but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
* Lesser General Public License for more details. | ||
* | ||
* You should have received a copy of the GNU Lesser General Public | ||
* License along with FFmpeg; if not, write to the Free Software | ||
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | ||
*/ | ||
|
||
#define DCT32_FLOAT 1 | ||
#include "dct32_template.c" |
Oops, something went wrong.