mirror of https://git.ffmpeg.org/ffmpeg.git
275 lines
8.4 KiB
C
275 lines
8.4 KiB
C
/*
|
|
* Copyright (c) 2013-2014 Mozilla Corporation
|
|
*
|
|
* This file is part of Libav.
|
|
*
|
|
* Libav 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.
|
|
*
|
|
* Libav 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 Libav; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
/**
|
|
* @file
|
|
* Celt non-power of 2 iMDCT
|
|
*/
|
|
|
|
#include <float.h>
|
|
#include <math.h>
|
|
#include <stddef.h>
|
|
|
|
#include "config.h"
|
|
|
|
#include "libavutil/attributes.h"
|
|
#include "libavutil/common.h"
|
|
|
|
#include "avfft.h"
|
|
#include "imdct15.h"
|
|
#include "opus.h"
|
|
|
|
// minimal iMDCT size to make SIMD opts easier
|
|
#define CELT_MIN_IMDCT_SIZE 120
|
|
|
|
// complex c = a * b
|
|
#define CMUL3(cre, cim, are, aim, bre, bim) \
|
|
do { \
|
|
cre = are * bre - aim * bim; \
|
|
cim = are * bim + aim * bre; \
|
|
} while (0)
|
|
|
|
#define CMUL(c, a, b) CMUL3((c).re, (c).im, (a).re, (a).im, (b).re, (b).im)
|
|
|
|
// complex c = a * b
|
|
// d = a * conjugate(b)
|
|
#define CMUL2(c, d, a, b) \
|
|
do { \
|
|
float are = (a).re; \
|
|
float aim = (a).im; \
|
|
float bre = (b).re; \
|
|
float bim = (b).im; \
|
|
float rr = are * bre; \
|
|
float ri = are * bim; \
|
|
float ir = aim * bre; \
|
|
float ii = aim * bim; \
|
|
(c).re = rr - ii; \
|
|
(c).im = ri + ir; \
|
|
(d).re = rr + ii; \
|
|
(d).im = -ri + ir; \
|
|
} while (0)
|
|
|
|
av_cold void ff_imdct15_uninit(IMDCT15Context **ps)
|
|
{
|
|
IMDCT15Context *s = *ps;
|
|
int i;
|
|
|
|
if (!s)
|
|
return;
|
|
|
|
for (i = 0; i < FF_ARRAY_ELEMS(s->exptab); i++)
|
|
av_freep(&s->exptab[i]);
|
|
|
|
av_freep(&s->twiddle_exptab);
|
|
|
|
av_freep(&s->tmp);
|
|
|
|
av_freep(ps);
|
|
}
|
|
|
|
static void imdct15_half(IMDCT15Context *s, float *dst, const float *src,
|
|
ptrdiff_t stride, float scale);
|
|
|
|
av_cold int ff_imdct15_init(IMDCT15Context **ps, int N)
|
|
{
|
|
IMDCT15Context *s;
|
|
int len2 = 15 * (1 << N);
|
|
int len = 2 * len2;
|
|
int i, j;
|
|
|
|
if (len2 > CELT_MAX_FRAME_SIZE || len2 < CELT_MIN_IMDCT_SIZE)
|
|
return AVERROR(EINVAL);
|
|
|
|
s = av_mallocz(sizeof(*s));
|
|
if (!s)
|
|
return AVERROR(ENOMEM);
|
|
|
|
s->fft_n = N - 1;
|
|
s->len4 = len2 / 2;
|
|
s->len2 = len2;
|
|
|
|
s->tmp = av_malloc(len * 2 * sizeof(*s->tmp));
|
|
if (!s->tmp)
|
|
goto fail;
|
|
|
|
s->twiddle_exptab = av_malloc(s->len4 * sizeof(*s->twiddle_exptab));
|
|
if (!s->twiddle_exptab)
|
|
goto fail;
|
|
|
|
for (i = 0; i < s->len4; i++) {
|
|
s->twiddle_exptab[i].re = cos(2 * M_PI * (i + 0.125 + s->len4) / len);
|
|
s->twiddle_exptab[i].im = sin(2 * M_PI * (i + 0.125 + s->len4) / len);
|
|
}
|
|
|
|
for (i = 0; i < FF_ARRAY_ELEMS(s->exptab); i++) {
|
|
int N = 15 * (1 << i);
|
|
s->exptab[i] = av_malloc(sizeof(*s->exptab[i]) * FFMAX(N, 19));
|
|
if (!s->exptab[i])
|
|
goto fail;
|
|
|
|
for (j = 0; j < N; j++) {
|
|
s->exptab[i][j].re = cos(2 * M_PI * j / N);
|
|
s->exptab[i][j].im = sin(2 * M_PI * j / N);
|
|
}
|
|
}
|
|
|
|
// wrap around to simplify fft15
|
|
for (j = 15; j < 19; j++)
|
|
s->exptab[0][j] = s->exptab[0][j - 15];
|
|
|
|
s->imdct_half = imdct15_half;
|
|
|
|
if (ARCH_AARCH64)
|
|
ff_imdct15_init_aarch64(s);
|
|
|
|
*ps = s;
|
|
|
|
return 0;
|
|
|
|
fail:
|
|
ff_imdct15_uninit(&s);
|
|
return AVERROR(ENOMEM);
|
|
}
|
|
|
|
static void fft5(FFTComplex *out, const FFTComplex *in, ptrdiff_t stride)
|
|
{
|
|
// [0] = exp(2 * i * pi / 5), [1] = exp(2 * i * pi * 2 / 5)
|
|
static const FFTComplex fact[] = { { 0.30901699437494745, 0.95105651629515353 },
|
|
{ -0.80901699437494734, 0.58778525229247325 } };
|
|
|
|
FFTComplex z[4][4];
|
|
|
|
CMUL2(z[0][0], z[0][3], in[1 * stride], fact[0]);
|
|
CMUL2(z[0][1], z[0][2], in[1 * stride], fact[1]);
|
|
CMUL2(z[1][0], z[1][3], in[2 * stride], fact[0]);
|
|
CMUL2(z[1][1], z[1][2], in[2 * stride], fact[1]);
|
|
CMUL2(z[2][0], z[2][3], in[3 * stride], fact[0]);
|
|
CMUL2(z[2][1], z[2][2], in[3 * stride], fact[1]);
|
|
CMUL2(z[3][0], z[3][3], in[4 * stride], fact[0]);
|
|
CMUL2(z[3][1], z[3][2], in[4 * stride], fact[1]);
|
|
|
|
out[0].re = in[0].re + in[stride].re + in[2 * stride].re + in[3 * stride].re + in[4 * stride].re;
|
|
out[0].im = in[0].im + in[stride].im + in[2 * stride].im + in[3 * stride].im + in[4 * stride].im;
|
|
|
|
out[1].re = in[0].re + z[0][0].re + z[1][1].re + z[2][2].re + z[3][3].re;
|
|
out[1].im = in[0].im + z[0][0].im + z[1][1].im + z[2][2].im + z[3][3].im;
|
|
|
|
out[2].re = in[0].re + z[0][1].re + z[1][3].re + z[2][0].re + z[3][2].re;
|
|
out[2].im = in[0].im + z[0][1].im + z[1][3].im + z[2][0].im + z[3][2].im;
|
|
|
|
out[3].re = in[0].re + z[0][2].re + z[1][0].re + z[2][3].re + z[3][1].re;
|
|
out[3].im = in[0].im + z[0][2].im + z[1][0].im + z[2][3].im + z[3][1].im;
|
|
|
|
out[4].re = in[0].re + z[0][3].re + z[1][2].re + z[2][1].re + z[3][0].re;
|
|
out[4].im = in[0].im + z[0][3].im + z[1][2].im + z[2][1].im + z[3][0].im;
|
|
}
|
|
|
|
static void fft15(IMDCT15Context *s, FFTComplex *out, const FFTComplex *in,
|
|
ptrdiff_t stride)
|
|
{
|
|
const FFTComplex *exptab = s->exptab[0];
|
|
FFTComplex tmp[5];
|
|
FFTComplex tmp1[5];
|
|
FFTComplex tmp2[5];
|
|
int k;
|
|
|
|
fft5(tmp, in, stride * 3);
|
|
fft5(tmp1, in + stride, stride * 3);
|
|
fft5(tmp2, in + 2 * stride, stride * 3);
|
|
|
|
for (k = 0; k < 5; k++) {
|
|
FFTComplex t1, t2;
|
|
|
|
CMUL(t1, tmp1[k], exptab[k]);
|
|
CMUL(t2, tmp2[k], exptab[2 * k]);
|
|
out[k].re = tmp[k].re + t1.re + t2.re;
|
|
out[k].im = tmp[k].im + t1.im + t2.im;
|
|
|
|
CMUL(t1, tmp1[k], exptab[k + 5]);
|
|
CMUL(t2, tmp2[k], exptab[2 * (k + 5)]);
|
|
out[k + 5].re = tmp[k].re + t1.re + t2.re;
|
|
out[k + 5].im = tmp[k].im + t1.im + t2.im;
|
|
|
|
CMUL(t1, tmp1[k], exptab[k + 10]);
|
|
CMUL(t2, tmp2[k], exptab[2 * k + 5]);
|
|
out[k + 10].re = tmp[k].re + t1.re + t2.re;
|
|
out[k + 10].im = tmp[k].im + t1.im + t2.im;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* FFT of the length 15 * (2^N)
|
|
*/
|
|
static void fft_calc(IMDCT15Context *s, FFTComplex *out, const FFTComplex *in,
|
|
int N, ptrdiff_t stride)
|
|
{
|
|
if (N) {
|
|
const FFTComplex *exptab = s->exptab[N];
|
|
const int len2 = 15 * (1 << (N - 1));
|
|
int k;
|
|
|
|
fft_calc(s, out, in, N - 1, stride * 2);
|
|
fft_calc(s, out + len2, in + stride, N - 1, stride * 2);
|
|
|
|
for (k = 0; k < len2; k++) {
|
|
FFTComplex t;
|
|
|
|
CMUL(t, out[len2 + k], exptab[k]);
|
|
|
|
out[len2 + k].re = out[k].re - t.re;
|
|
out[len2 + k].im = out[k].im - t.im;
|
|
|
|
out[k].re += t.re;
|
|
out[k].im += t.im;
|
|
}
|
|
} else
|
|
fft15(s, out, in, stride);
|
|
}
|
|
|
|
static void imdct15_half(IMDCT15Context *s, float *dst, const float *src,
|
|
ptrdiff_t stride, float scale)
|
|
{
|
|
FFTComplex *z = (FFTComplex *)dst;
|
|
const int len8 = s->len4 / 2;
|
|
const float *in1 = src;
|
|
const float *in2 = src + (s->len2 - 1) * stride;
|
|
int i;
|
|
|
|
for (i = 0; i < s->len4; i++) {
|
|
FFTComplex tmp = { *in2, *in1 };
|
|
CMUL(s->tmp[i], tmp, s->twiddle_exptab[i]);
|
|
in1 += 2 * stride;
|
|
in2 -= 2 * stride;
|
|
}
|
|
|
|
fft_calc(s, z, s->tmp, s->fft_n, 1);
|
|
|
|
for (i = 0; i < len8; i++) {
|
|
float r0, i0, r1, i1;
|
|
|
|
CMUL3(r0, i1, z[len8 - i - 1].im, z[len8 - i - 1].re, s->twiddle_exptab[len8 - i - 1].im, s->twiddle_exptab[len8 - i - 1].re);
|
|
CMUL3(r1, i0, z[len8 + i].im, z[len8 + i].re, s->twiddle_exptab[len8 + i].im, s->twiddle_exptab[len8 + i].re);
|
|
z[len8 - i - 1].re = scale * r0;
|
|
z[len8 - i - 1].im = scale * i0;
|
|
z[len8 + i].re = scale * r1;
|
|
z[len8 + i].im = scale * i1;
|
|
}
|
|
}
|