ffmpeg/libavutil/tx_template.c
Lynne 1978b143eb
checkasm: add av_tx FFT SIMD testing code
This sadly required making changes to the code itself,
due to the same context needing to be reused for both versions.
The lookup table had to be duplicated for both versions.
2021-04-24 17:19:17 +02:00

1025 lines
41 KiB
C

/*
* Copyright (c) Lynne
*
* Power of two FFT:
* Copyright (c) Lynne
* Copyright (c) 2008 Loren Merritt
* Copyright (c) 2002 Fabrice Bellard
* Partly based on libdjbfft by D. J. Bernstein
*
* 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
*/
/* All costabs for a type are defined here */
COSTABLE(16);
COSTABLE(32);
COSTABLE(64);
COSTABLE(128);
COSTABLE(256);
COSTABLE(512);
COSTABLE(1024);
COSTABLE(2048);
COSTABLE(4096);
COSTABLE(8192);
COSTABLE(16384);
COSTABLE(32768);
COSTABLE(65536);
COSTABLE(131072);
DECLARE_ALIGNED(32, FFTComplex, TX_NAME(ff_cos_53))[4];
DECLARE_ALIGNED(32, FFTComplex, TX_NAME(ff_cos_7))[3];
DECLARE_ALIGNED(32, FFTComplex, TX_NAME(ff_cos_9))[4];
static FFTSample * const cos_tabs[18] = {
NULL,
NULL,
NULL,
NULL,
TX_NAME(ff_cos_16),
TX_NAME(ff_cos_32),
TX_NAME(ff_cos_64),
TX_NAME(ff_cos_128),
TX_NAME(ff_cos_256),
TX_NAME(ff_cos_512),
TX_NAME(ff_cos_1024),
TX_NAME(ff_cos_2048),
TX_NAME(ff_cos_4096),
TX_NAME(ff_cos_8192),
TX_NAME(ff_cos_16384),
TX_NAME(ff_cos_32768),
TX_NAME(ff_cos_65536),
TX_NAME(ff_cos_131072),
};
static av_always_inline void init_cos_tabs_idx(int index)
{
int m = 1 << index;
double freq = 2*M_PI/m;
FFTSample *tab = cos_tabs[index];
for (int i = 0; i < m/4; i++)
*tab++ = RESCALE(cos(i*freq));
*tab = 0;
}
#define INIT_FF_COS_TABS_FUNC(index, size) \
static av_cold void init_cos_tabs_ ## size (void) \
{ \
init_cos_tabs_idx(index); \
}
INIT_FF_COS_TABS_FUNC(4, 16)
INIT_FF_COS_TABS_FUNC(5, 32)
INIT_FF_COS_TABS_FUNC(6, 64)
INIT_FF_COS_TABS_FUNC(7, 128)
INIT_FF_COS_TABS_FUNC(8, 256)
INIT_FF_COS_TABS_FUNC(9, 512)
INIT_FF_COS_TABS_FUNC(10, 1024)
INIT_FF_COS_TABS_FUNC(11, 2048)
INIT_FF_COS_TABS_FUNC(12, 4096)
INIT_FF_COS_TABS_FUNC(13, 8192)
INIT_FF_COS_TABS_FUNC(14, 16384)
INIT_FF_COS_TABS_FUNC(15, 32768)
INIT_FF_COS_TABS_FUNC(16, 65536)
INIT_FF_COS_TABS_FUNC(17, 131072)
static av_cold void ff_init_53_tabs(void)
{
TX_NAME(ff_cos_53)[0] = (FFTComplex){ RESCALE(cos(2 * M_PI / 12)), RESCALE(cos(2 * M_PI / 12)) };
TX_NAME(ff_cos_53)[1] = (FFTComplex){ RESCALE(cos(2 * M_PI / 6)), RESCALE(cos(2 * M_PI / 6)) };
TX_NAME(ff_cos_53)[2] = (FFTComplex){ RESCALE(cos(2 * M_PI / 5)), RESCALE(sin(2 * M_PI / 5)) };
TX_NAME(ff_cos_53)[3] = (FFTComplex){ RESCALE(cos(2 * M_PI / 10)), RESCALE(sin(2 * M_PI / 10)) };
}
static av_cold void ff_init_7_tabs(void)
{
TX_NAME(ff_cos_7)[0] = (FFTComplex){ RESCALE(cos(2 * M_PI / 7)), RESCALE(sin(2 * M_PI / 7)) };
TX_NAME(ff_cos_7)[1] = (FFTComplex){ RESCALE(sin(2 * M_PI / 28)), RESCALE(cos(2 * M_PI / 28)) };
TX_NAME(ff_cos_7)[2] = (FFTComplex){ RESCALE(cos(2 * M_PI / 14)), RESCALE(sin(2 * M_PI / 14)) };
}
static av_cold void ff_init_9_tabs(void)
{
TX_NAME(ff_cos_9)[0] = (FFTComplex){ RESCALE(cos(2 * M_PI / 3)), RESCALE( sin(2 * M_PI / 3)) };
TX_NAME(ff_cos_9)[1] = (FFTComplex){ RESCALE(cos(2 * M_PI / 9)), RESCALE( sin(2 * M_PI / 9)) };
TX_NAME(ff_cos_9)[2] = (FFTComplex){ RESCALE(cos(2 * M_PI / 36)), RESCALE( sin(2 * M_PI / 36)) };
TX_NAME(ff_cos_9)[3] = (FFTComplex){ TX_NAME(ff_cos_9)[1].re + TX_NAME(ff_cos_9)[2].im,
TX_NAME(ff_cos_9)[1].im - TX_NAME(ff_cos_9)[2].re };
}
static CosTabsInitOnce cos_tabs_init_once[] = {
{ ff_init_53_tabs, AV_ONCE_INIT },
{ ff_init_7_tabs, AV_ONCE_INIT },
{ ff_init_9_tabs, AV_ONCE_INIT },
{ NULL },
{ init_cos_tabs_16, AV_ONCE_INIT },
{ init_cos_tabs_32, AV_ONCE_INIT },
{ init_cos_tabs_64, AV_ONCE_INIT },
{ init_cos_tabs_128, AV_ONCE_INIT },
{ init_cos_tabs_256, AV_ONCE_INIT },
{ init_cos_tabs_512, AV_ONCE_INIT },
{ init_cos_tabs_1024, AV_ONCE_INIT },
{ init_cos_tabs_2048, AV_ONCE_INIT },
{ init_cos_tabs_4096, AV_ONCE_INIT },
{ init_cos_tabs_8192, AV_ONCE_INIT },
{ init_cos_tabs_16384, AV_ONCE_INIT },
{ init_cos_tabs_32768, AV_ONCE_INIT },
{ init_cos_tabs_65536, AV_ONCE_INIT },
{ init_cos_tabs_131072, AV_ONCE_INIT },
};
static av_cold void init_cos_tabs(int index)
{
ff_thread_once(&cos_tabs_init_once[index].control,
cos_tabs_init_once[index].func);
}
static av_always_inline void fft3(FFTComplex *out, FFTComplex *in,
ptrdiff_t stride)
{
FFTComplex tmp[2];
#ifdef TX_INT32
int64_t mtmp[4];
#endif
BF(tmp[0].re, tmp[1].im, in[1].im, in[2].im);
BF(tmp[0].im, tmp[1].re, in[1].re, in[2].re);
out[0*stride].re = in[0].re + tmp[1].re;
out[0*stride].im = in[0].im + tmp[1].im;
#ifdef TX_INT32
mtmp[0] = (int64_t)TX_NAME(ff_cos_53)[0].re * tmp[0].re;
mtmp[1] = (int64_t)TX_NAME(ff_cos_53)[0].im * tmp[0].im;
mtmp[2] = (int64_t)TX_NAME(ff_cos_53)[1].re * tmp[1].re;
mtmp[3] = (int64_t)TX_NAME(ff_cos_53)[1].re * tmp[1].im;
out[1*stride].re = in[0].re - (mtmp[2] + mtmp[0] + 0x40000000 >> 31);
out[1*stride].im = in[0].im - (mtmp[3] - mtmp[1] + 0x40000000 >> 31);
out[2*stride].re = in[0].re - (mtmp[2] - mtmp[0] + 0x40000000 >> 31);
out[2*stride].im = in[0].im - (mtmp[3] + mtmp[1] + 0x40000000 >> 31);
#else
tmp[0].re = TX_NAME(ff_cos_53)[0].re * tmp[0].re;
tmp[0].im = TX_NAME(ff_cos_53)[0].im * tmp[0].im;
tmp[1].re = TX_NAME(ff_cos_53)[1].re * tmp[1].re;
tmp[1].im = TX_NAME(ff_cos_53)[1].re * tmp[1].im;
out[1*stride].re = in[0].re - tmp[1].re + tmp[0].re;
out[1*stride].im = in[0].im - tmp[1].im - tmp[0].im;
out[2*stride].re = in[0].re - tmp[1].re - tmp[0].re;
out[2*stride].im = in[0].im - tmp[1].im + tmp[0].im;
#endif
}
#define DECL_FFT5(NAME, D0, D1, D2, D3, D4) \
static av_always_inline void NAME(FFTComplex *out, FFTComplex *in, \
ptrdiff_t stride) \
{ \
FFTComplex z0[4], t[6]; \
\
BF(t[1].im, t[0].re, in[1].re, in[4].re); \
BF(t[1].re, t[0].im, in[1].im, in[4].im); \
BF(t[3].im, t[2].re, in[2].re, in[3].re); \
BF(t[3].re, t[2].im, in[2].im, in[3].im); \
\
out[D0*stride].re = in[0].re + t[0].re + t[2].re; \
out[D0*stride].im = in[0].im + t[0].im + t[2].im; \
\
SMUL(t[4].re, t[0].re, TX_NAME(ff_cos_53)[2].re, TX_NAME(ff_cos_53)[3].re, t[2].re, t[0].re); \
SMUL(t[4].im, t[0].im, TX_NAME(ff_cos_53)[2].re, TX_NAME(ff_cos_53)[3].re, t[2].im, t[0].im); \
CMUL(t[5].re, t[1].re, TX_NAME(ff_cos_53)[2].im, TX_NAME(ff_cos_53)[3].im, t[3].re, t[1].re); \
CMUL(t[5].im, t[1].im, TX_NAME(ff_cos_53)[2].im, TX_NAME(ff_cos_53)[3].im, t[3].im, t[1].im); \
\
BF(z0[0].re, z0[3].re, t[0].re, t[1].re); \
BF(z0[0].im, z0[3].im, t[0].im, t[1].im); \
BF(z0[2].re, z0[1].re, t[4].re, t[5].re); \
BF(z0[2].im, z0[1].im, t[4].im, t[5].im); \
\
out[D1*stride].re = in[0].re + z0[3].re; \
out[D1*stride].im = in[0].im + z0[0].im; \
out[D2*stride].re = in[0].re + z0[2].re; \
out[D2*stride].im = in[0].im + z0[1].im; \
out[D3*stride].re = in[0].re + z0[1].re; \
out[D3*stride].im = in[0].im + z0[2].im; \
out[D4*stride].re = in[0].re + z0[0].re; \
out[D4*stride].im = in[0].im + z0[3].im; \
}
DECL_FFT5(fft5, 0, 1, 2, 3, 4)
DECL_FFT5(fft5_m1, 0, 6, 12, 3, 9)
DECL_FFT5(fft5_m2, 10, 1, 7, 13, 4)
DECL_FFT5(fft5_m3, 5, 11, 2, 8, 14)
static av_always_inline void fft7(FFTComplex *out, FFTComplex *in,
ptrdiff_t stride)
{
FFTComplex t[6], z[3];
const FFTComplex *tab = TX_NAME(ff_cos_7);
#ifdef TX_INT32
int64_t mtmp[12];
#endif
BF(t[1].re, t[0].re, in[1].re, in[6].re);
BF(t[1].im, t[0].im, in[1].im, in[6].im);
BF(t[3].re, t[2].re, in[2].re, in[5].re);
BF(t[3].im, t[2].im, in[2].im, in[5].im);
BF(t[5].re, t[4].re, in[3].re, in[4].re);
BF(t[5].im, t[4].im, in[3].im, in[4].im);
out[0*stride].re = in[0].re + t[0].re + t[2].re + t[4].re;
out[0*stride].im = in[0].im + t[0].im + t[2].im + t[4].im;
#ifdef TX_INT32 /* NOTE: it's possible to do this with 16 mults but 72 adds */
mtmp[ 0] = ((int64_t)tab[0].re)*t[0].re - ((int64_t)tab[2].re)*t[4].re;
mtmp[ 1] = ((int64_t)tab[0].re)*t[4].re - ((int64_t)tab[1].re)*t[0].re;
mtmp[ 2] = ((int64_t)tab[0].re)*t[2].re - ((int64_t)tab[2].re)*t[0].re;
mtmp[ 3] = ((int64_t)tab[0].re)*t[0].im - ((int64_t)tab[1].re)*t[2].im;
mtmp[ 4] = ((int64_t)tab[0].re)*t[4].im - ((int64_t)tab[1].re)*t[0].im;
mtmp[ 5] = ((int64_t)tab[0].re)*t[2].im - ((int64_t)tab[2].re)*t[0].im;
mtmp[ 6] = ((int64_t)tab[2].im)*t[1].im + ((int64_t)tab[1].im)*t[5].im;
mtmp[ 7] = ((int64_t)tab[0].im)*t[5].im + ((int64_t)tab[2].im)*t[3].im;
mtmp[ 8] = ((int64_t)tab[2].im)*t[5].im + ((int64_t)tab[1].im)*t[3].im;
mtmp[ 9] = ((int64_t)tab[0].im)*t[1].re + ((int64_t)tab[1].im)*t[3].re;
mtmp[10] = ((int64_t)tab[2].im)*t[3].re + ((int64_t)tab[0].im)*t[5].re;
mtmp[11] = ((int64_t)tab[2].im)*t[1].re + ((int64_t)tab[1].im)*t[5].re;
z[0].re = (int32_t)(mtmp[ 0] - ((int64_t)tab[1].re)*t[2].re + 0x40000000 >> 31);
z[1].re = (int32_t)(mtmp[ 1] - ((int64_t)tab[2].re)*t[2].re + 0x40000000 >> 31);
z[2].re = (int32_t)(mtmp[ 2] - ((int64_t)tab[1].re)*t[4].re + 0x40000000 >> 31);
z[0].im = (int32_t)(mtmp[ 3] - ((int64_t)tab[2].re)*t[4].im + 0x40000000 >> 31);
z[1].im = (int32_t)(mtmp[ 4] - ((int64_t)tab[2].re)*t[2].im + 0x40000000 >> 31);
z[2].im = (int32_t)(mtmp[ 5] - ((int64_t)tab[1].re)*t[4].im + 0x40000000 >> 31);
t[0].re = (int32_t)(mtmp[ 6] - ((int64_t)tab[0].im)*t[3].im + 0x40000000 >> 31);
t[2].re = (int32_t)(mtmp[ 7] - ((int64_t)tab[1].im)*t[1].im + 0x40000000 >> 31);
t[4].re = (int32_t)(mtmp[ 8] + ((int64_t)tab[0].im)*t[1].im + 0x40000000 >> 31);
t[0].im = (int32_t)(mtmp[ 9] + ((int64_t)tab[2].im)*t[5].re + 0x40000000 >> 31);
t[2].im = (int32_t)(mtmp[10] - ((int64_t)tab[1].im)*t[1].re + 0x40000000 >> 31);
t[4].im = (int32_t)(mtmp[11] - ((int64_t)tab[0].im)*t[3].re + 0x40000000 >> 31);
#else
z[0].re = tab[0].re*t[0].re - tab[2].re*t[4].re - tab[1].re*t[2].re;
z[1].re = tab[0].re*t[4].re - tab[1].re*t[0].re - tab[2].re*t[2].re;
z[2].re = tab[0].re*t[2].re - tab[2].re*t[0].re - tab[1].re*t[4].re;
z[0].im = tab[0].re*t[0].im - tab[1].re*t[2].im - tab[2].re*t[4].im;
z[1].im = tab[0].re*t[4].im - tab[1].re*t[0].im - tab[2].re*t[2].im;
z[2].im = tab[0].re*t[2].im - tab[2].re*t[0].im - tab[1].re*t[4].im;
/* It's possible to do t[4].re and t[0].im with 2 multiplies only by
* multiplying the sum of all with the average of the twiddles */
t[0].re = tab[2].im*t[1].im + tab[1].im*t[5].im - tab[0].im*t[3].im;
t[2].re = tab[0].im*t[5].im + tab[2].im*t[3].im - tab[1].im*t[1].im;
t[4].re = tab[2].im*t[5].im + tab[1].im*t[3].im + tab[0].im*t[1].im;
t[0].im = tab[0].im*t[1].re + tab[1].im*t[3].re + tab[2].im*t[5].re;
t[2].im = tab[2].im*t[3].re + tab[0].im*t[5].re - tab[1].im*t[1].re;
t[4].im = tab[2].im*t[1].re + tab[1].im*t[5].re - tab[0].im*t[3].re;
#endif
BF(t[1].re, z[0].re, z[0].re, t[4].re);
BF(t[3].re, z[1].re, z[1].re, t[2].re);
BF(t[5].re, z[2].re, z[2].re, t[0].re);
BF(t[1].im, z[0].im, z[0].im, t[0].im);
BF(t[3].im, z[1].im, z[1].im, t[2].im);
BF(t[5].im, z[2].im, z[2].im, t[4].im);
out[1*stride].re = in[0].re + z[0].re;
out[1*stride].im = in[0].im + t[1].im;
out[2*stride].re = in[0].re + t[3].re;
out[2*stride].im = in[0].im + z[1].im;
out[3*stride].re = in[0].re + z[2].re;
out[3*stride].im = in[0].im + t[5].im;
out[4*stride].re = in[0].re + t[5].re;
out[4*stride].im = in[0].im + z[2].im;
out[5*stride].re = in[0].re + z[1].re;
out[5*stride].im = in[0].im + t[3].im;
out[6*stride].re = in[0].re + t[1].re;
out[6*stride].im = in[0].im + z[0].im;
}
static av_always_inline void fft9(FFTComplex *out, FFTComplex *in,
ptrdiff_t stride)
{
const FFTComplex *tab = TX_NAME(ff_cos_9);
FFTComplex t[16], w[4], x[5], y[5], z[2];
#ifdef TX_INT32
int64_t mtmp[12];
#endif
BF(t[1].re, t[0].re, in[1].re, in[8].re);
BF(t[1].im, t[0].im, in[1].im, in[8].im);
BF(t[3].re, t[2].re, in[2].re, in[7].re);
BF(t[3].im, t[2].im, in[2].im, in[7].im);
BF(t[5].re, t[4].re, in[3].re, in[6].re);
BF(t[5].im, t[4].im, in[3].im, in[6].im);
BF(t[7].re, t[6].re, in[4].re, in[5].re);
BF(t[7].im, t[6].im, in[4].im, in[5].im);
w[0].re = t[0].re - t[6].re;
w[0].im = t[0].im - t[6].im;
w[1].re = t[2].re - t[6].re;
w[1].im = t[2].im - t[6].im;
w[2].re = t[1].re - t[7].re;
w[2].im = t[1].im - t[7].im;
w[3].re = t[3].re + t[7].re;
w[3].im = t[3].im + t[7].im;
z[0].re = in[0].re + t[4].re;
z[0].im = in[0].im + t[4].im;
z[1].re = t[0].re + t[2].re + t[6].re;
z[1].im = t[0].im + t[2].im + t[6].im;
out[0*stride].re = z[0].re + z[1].re;
out[0*stride].im = z[0].im + z[1].im;
#ifdef TX_INT32
mtmp[0] = t[1].re - t[3].re + t[7].re;
mtmp[1] = t[1].im - t[3].im + t[7].im;
y[3].re = (int32_t)(((int64_t)tab[0].im)*mtmp[0] + 0x40000000 >> 31);
y[3].im = (int32_t)(((int64_t)tab[0].im)*mtmp[1] + 0x40000000 >> 31);
mtmp[0] = (int32_t)(((int64_t)tab[0].re)*z[1].re + 0x40000000 >> 31);
mtmp[1] = (int32_t)(((int64_t)tab[0].re)*z[1].im + 0x40000000 >> 31);
mtmp[2] = (int32_t)(((int64_t)tab[0].re)*t[4].re + 0x40000000 >> 31);
mtmp[3] = (int32_t)(((int64_t)tab[0].re)*t[4].im + 0x40000000 >> 31);
x[3].re = z[0].re + (int32_t)mtmp[0];
x[3].im = z[0].im + (int32_t)mtmp[1];
z[0].re = in[0].re + (int32_t)mtmp[2];
z[0].im = in[0].im + (int32_t)mtmp[3];
mtmp[0] = ((int64_t)tab[1].re)*w[0].re;
mtmp[1] = ((int64_t)tab[1].re)*w[0].im;
mtmp[2] = ((int64_t)tab[2].im)*w[0].re;
mtmp[3] = ((int64_t)tab[2].im)*w[0].im;
mtmp[4] = ((int64_t)tab[1].im)*w[2].re;
mtmp[5] = ((int64_t)tab[1].im)*w[2].im;
mtmp[6] = ((int64_t)tab[2].re)*w[2].re;
mtmp[7] = ((int64_t)tab[2].re)*w[2].im;
x[1].re = (int32_t)(mtmp[0] + ((int64_t)tab[2].im)*w[1].re + 0x40000000 >> 31);
x[1].im = (int32_t)(mtmp[1] + ((int64_t)tab[2].im)*w[1].im + 0x40000000 >> 31);
x[2].re = (int32_t)(mtmp[2] - ((int64_t)tab[3].re)*w[1].re + 0x40000000 >> 31);
x[2].im = (int32_t)(mtmp[3] - ((int64_t)tab[3].re)*w[1].im + 0x40000000 >> 31);
y[1].re = (int32_t)(mtmp[4] + ((int64_t)tab[2].re)*w[3].re + 0x40000000 >> 31);
y[1].im = (int32_t)(mtmp[5] + ((int64_t)tab[2].re)*w[3].im + 0x40000000 >> 31);
y[2].re = (int32_t)(mtmp[6] - ((int64_t)tab[3].im)*w[3].re + 0x40000000 >> 31);
y[2].im = (int32_t)(mtmp[7] - ((int64_t)tab[3].im)*w[3].im + 0x40000000 >> 31);
y[0].re = (int32_t)(((int64_t)tab[0].im)*t[5].re + 0x40000000 >> 31);
y[0].im = (int32_t)(((int64_t)tab[0].im)*t[5].im + 0x40000000 >> 31);
#else
y[3].re = tab[0].im*(t[1].re - t[3].re + t[7].re);
y[3].im = tab[0].im*(t[1].im - t[3].im + t[7].im);
x[3].re = z[0].re + tab[0].re*z[1].re;
x[3].im = z[0].im + tab[0].re*z[1].im;
z[0].re = in[0].re + tab[0].re*t[4].re;
z[0].im = in[0].im + tab[0].re*t[4].im;
x[1].re = tab[1].re*w[0].re + tab[2].im*w[1].re;
x[1].im = tab[1].re*w[0].im + tab[2].im*w[1].im;
x[2].re = tab[2].im*w[0].re - tab[3].re*w[1].re;
x[2].im = tab[2].im*w[0].im - tab[3].re*w[1].im;
y[1].re = tab[1].im*w[2].re + tab[2].re*w[3].re;
y[1].im = tab[1].im*w[2].im + tab[2].re*w[3].im;
y[2].re = tab[2].re*w[2].re - tab[3].im*w[3].re;
y[2].im = tab[2].re*w[2].im - tab[3].im*w[3].im;
y[0].re = tab[0].im*t[5].re;
y[0].im = tab[0].im*t[5].im;
#endif
x[4].re = x[1].re + x[2].re;
x[4].im = x[1].im + x[2].im;
y[4].re = y[1].re - y[2].re;
y[4].im = y[1].im - y[2].im;
x[1].re = z[0].re + x[1].re;
x[1].im = z[0].im + x[1].im;
y[1].re = y[0].re + y[1].re;
y[1].im = y[0].im + y[1].im;
x[2].re = z[0].re + x[2].re;
x[2].im = z[0].im + x[2].im;
y[2].re = y[2].re - y[0].re;
y[2].im = y[2].im - y[0].im;
x[4].re = z[0].re - x[4].re;
x[4].im = z[0].im - x[4].im;
y[4].re = y[0].re - y[4].re;
y[4].im = y[0].im - y[4].im;
out[1*stride] = (FFTComplex){ x[1].re + y[1].im, x[1].im - y[1].re };
out[2*stride] = (FFTComplex){ x[2].re + y[2].im, x[2].im - y[2].re };
out[3*stride] = (FFTComplex){ x[3].re + y[3].im, x[3].im - y[3].re };
out[4*stride] = (FFTComplex){ x[4].re + y[4].im, x[4].im - y[4].re };
out[5*stride] = (FFTComplex){ x[4].re - y[4].im, x[4].im + y[4].re };
out[6*stride] = (FFTComplex){ x[3].re - y[3].im, x[3].im + y[3].re };
out[7*stride] = (FFTComplex){ x[2].re - y[2].im, x[2].im + y[2].re };
out[8*stride] = (FFTComplex){ x[1].re - y[1].im, x[1].im + y[1].re };
}
static av_always_inline void fft15(FFTComplex *out, FFTComplex *in,
ptrdiff_t stride)
{
FFTComplex tmp[15];
for (int i = 0; i < 5; i++)
fft3(tmp + i, in + i*3, 5);
fft5_m1(out, tmp + 0, stride);
fft5_m2(out, tmp + 5, stride);
fft5_m3(out, tmp + 10, stride);
}
#define BUTTERFLIES(a0,a1,a2,a3) \
do { \
r0=a0.re; \
i0=a0.im; \
r1=a1.re; \
i1=a1.im; \
BF(t3, t5, t5, t1); \
BF(a2.re, a0.re, r0, t5); \
BF(a3.im, a1.im, i1, t3); \
BF(t4, t6, t2, t6); \
BF(a3.re, a1.re, r1, t4); \
BF(a2.im, a0.im, i0, t6); \
} while (0)
#define TRANSFORM(a0,a1,a2,a3,wre,wim) \
do { \
CMUL(t1, t2, a2.re, a2.im, wre, -wim); \
CMUL(t5, t6, a3.re, a3.im, wre, wim); \
BUTTERFLIES(a0, a1, a2, a3); \
} while (0)
/* z[0...8n-1], w[1...2n-1] */
static void split_radix_combine(FFTComplex *z, const FFTSample *cos, int n)
{
int o1 = 2*n;
int o2 = 4*n;
int o3 = 6*n;
const FFTSample *wim = cos + o1 - 7;
FFTSample t1, t2, t3, t4, t5, t6, r0, i0, r1, i1;
for (int i = 0; i < n; i += 4) {
TRANSFORM(z[0], z[o1 + 0], z[o2 + 0], z[o3 + 0], cos[0], wim[7]);
TRANSFORM(z[2], z[o1 + 2], z[o2 + 2], z[o3 + 2], cos[2], wim[5]);
TRANSFORM(z[4], z[o1 + 4], z[o2 + 4], z[o3 + 4], cos[4], wim[3]);
TRANSFORM(z[6], z[o1 + 6], z[o2 + 6], z[o3 + 6], cos[6], wim[1]);
TRANSFORM(z[1], z[o1 + 1], z[o2 + 1], z[o3 + 1], cos[1], wim[6]);
TRANSFORM(z[3], z[o1 + 3], z[o2 + 3], z[o3 + 3], cos[3], wim[4]);
TRANSFORM(z[5], z[o1 + 5], z[o2 + 5], z[o3 + 5], cos[5], wim[2]);
TRANSFORM(z[7], z[o1 + 7], z[o2 + 7], z[o3 + 7], cos[7], wim[0]);
z += 2*4;
cos += 2*4;
wim -= 2*4;
}
}
#define DECL_FFT(n, n2, n4) \
static void fft##n(FFTComplex *z) \
{ \
fft##n2(z); \
fft##n4(z + n4*2); \
fft##n4(z + n4*3); \
split_radix_combine(z, TX_NAME(ff_cos_##n), n4/2); \
}
static void fft2(FFTComplex *z)
{
FFTComplex tmp;
BF(tmp.re, z[0].re, z[0].re, z[1].re);
BF(tmp.im, z[0].im, z[0].im, z[1].im);
z[1] = tmp;
}
static void fft4(FFTComplex *z)
{
FFTSample t1, t2, t3, t4, t5, t6, t7, t8;
BF(t3, t1, z[0].re, z[1].re);
BF(t8, t6, z[3].re, z[2].re);
BF(z[2].re, z[0].re, t1, t6);
BF(t4, t2, z[0].im, z[1].im);
BF(t7, t5, z[2].im, z[3].im);
BF(z[3].im, z[1].im, t4, t8);
BF(z[3].re, z[1].re, t3, t7);
BF(z[2].im, z[0].im, t2, t5);
}
static void fft8(FFTComplex *z)
{
FFTSample t1, t2, t3, t4, t5, t6, r0, i0, r1, i1;
fft4(z);
BF(t1, z[5].re, z[4].re, -z[5].re);
BF(t2, z[5].im, z[4].im, -z[5].im);
BF(t5, z[7].re, z[6].re, -z[7].re);
BF(t6, z[7].im, z[6].im, -z[7].im);
BUTTERFLIES(z[0], z[2], z[4], z[6]);
TRANSFORM(z[1], z[3], z[5], z[7], RESCALE(M_SQRT1_2), RESCALE(M_SQRT1_2));
}
static void fft16(FFTComplex *z)
{
FFTSample t1, t2, t3, t4, t5, t6, r0, i0, r1, i1;
FFTSample cos_16_1 = TX_NAME(ff_cos_16)[1];
FFTSample cos_16_2 = TX_NAME(ff_cos_16)[2];
FFTSample cos_16_3 = TX_NAME(ff_cos_16)[3];
fft8(z + 0);
fft4(z + 8);
fft4(z + 12);
t1 = z[ 8].re;
t2 = z[ 8].im;
t5 = z[12].re;
t6 = z[12].im;
BUTTERFLIES(z[0], z[4], z[8], z[12]);
TRANSFORM(z[ 2], z[ 6], z[10], z[14], cos_16_2, cos_16_2);
TRANSFORM(z[ 1], z[ 5], z[ 9], z[13], cos_16_1, cos_16_3);
TRANSFORM(z[ 3], z[ 7], z[11], z[15], cos_16_3, cos_16_1);
}
DECL_FFT(32,16,8)
DECL_FFT(64,32,16)
DECL_FFT(128,64,32)
DECL_FFT(256,128,64)
DECL_FFT(512,256,128)
DECL_FFT(1024,512,256)
DECL_FFT(2048,1024,512)
DECL_FFT(4096,2048,1024)
DECL_FFT(8192,4096,2048)
DECL_FFT(16384,8192,4096)
DECL_FFT(32768,16384,8192)
DECL_FFT(65536,32768,16384)
DECL_FFT(131072,65536,32768)
static void (* const fft_dispatch[])(FFTComplex*) = {
NULL, fft2, fft4, fft8, fft16, fft32, fft64, fft128, fft256, fft512,
fft1024, fft2048, fft4096, fft8192, fft16384, fft32768, fft65536, fft131072
};
#define DECL_COMP_FFT(N) \
static void compound_fft_##N##xM(AVTXContext *s, void *_out, \
void *_in, ptrdiff_t stride) \
{ \
const int m = s->m, *in_map = s->pfatab, *out_map = in_map + N*m; \
FFTComplex *in = _in; \
FFTComplex *out = _out; \
FFTComplex fft##N##in[N]; \
void (*fftp)(FFTComplex *z) = fft_dispatch[av_log2(m)]; \
\
for (int i = 0; i < m; i++) { \
for (int j = 0; j < N; j++) \
fft##N##in[j] = in[in_map[i*N + j]]; \
fft##N(s->tmp + s->revtab_c[i], fft##N##in, m); \
} \
\
for (int i = 0; i < N; i++) \
fftp(s->tmp + m*i); \
\
for (int i = 0; i < N*m; i++) \
out[i] = s->tmp[out_map[i]]; \
}
DECL_COMP_FFT(3)
DECL_COMP_FFT(5)
DECL_COMP_FFT(7)
DECL_COMP_FFT(9)
DECL_COMP_FFT(15)
static void split_radix_fft(AVTXContext *s, void *_out, void *_in,
ptrdiff_t stride)
{
FFTComplex *in = _in;
FFTComplex *out = _out;
int m = s->m, mb = av_log2(m);
if (s->flags & AV_TX_INPLACE) {
FFTComplex tmp;
int src, dst, *inplace_idx = s->inplace_idx;
src = *inplace_idx++;
do {
tmp = out[src];
dst = s->revtab_c[src];
do {
FFSWAP(FFTComplex, tmp, out[dst]);
dst = s->revtab_c[dst];
} while (dst != src); /* Can be > as well, but is less predictable */
out[dst] = tmp;
} while ((src = *inplace_idx++));
} else {
for (int i = 0; i < m; i++)
out[i] = in[s->revtab_c[i]];
}
fft_dispatch[mb](out);
}
static void naive_fft(AVTXContext *s, void *_out, void *_in,
ptrdiff_t stride)
{
FFTComplex *in = _in;
FFTComplex *out = _out;
const int n = s->n;
double phase = s->inv ? 2.0*M_PI/n : -2.0*M_PI/n;
for(int i = 0; i < n; i++) {
FFTComplex tmp = { 0 };
for(int j = 0; j < n; j++) {
const double factor = phase*i*j;
const FFTComplex mult = {
RESCALE(cos(factor)),
RESCALE(sin(factor)),
};
FFTComplex res;
CMUL3(res, in[j], mult);
tmp.re += res.re;
tmp.im += res.im;
}
out[i] = tmp;
}
}
#define DECL_COMP_IMDCT(N) \
static void compound_imdct_##N##xM(AVTXContext *s, void *_dst, void *_src, \
ptrdiff_t stride) \
{ \
FFTComplex fft##N##in[N]; \
FFTComplex *z = _dst, *exp = s->exptab; \
const int m = s->m, len8 = N*m >> 1; \
const int *in_map = s->pfatab, *out_map = in_map + N*m; \
const FFTSample *src = _src, *in1, *in2; \
void (*fftp)(FFTComplex *) = fft_dispatch[av_log2(m)]; \
\
stride /= sizeof(*src); /* To convert it from bytes */ \
in1 = src; \
in2 = src + ((N*m*2) - 1) * stride; \
\
for (int i = 0; i < m; i++) { \
for (int j = 0; j < N; j++) { \
const int k = in_map[i*N + j]; \
FFTComplex tmp = { in2[-k*stride], in1[k*stride] }; \
CMUL3(fft##N##in[j], tmp, exp[k >> 1]); \
} \
fft##N(s->tmp + s->revtab_c[i], fft##N##in, m); \
} \
\
for (int i = 0; i < N; i++) \
fftp(s->tmp + m*i); \
\
for (int i = 0; i < len8; i++) { \
const int i0 = len8 + i, i1 = len8 - i - 1; \
const int s0 = out_map[i0], s1 = out_map[i1]; \
FFTComplex src1 = { s->tmp[s1].im, s->tmp[s1].re }; \
FFTComplex src0 = { s->tmp[s0].im, s->tmp[s0].re }; \
\
CMUL(z[i1].re, z[i0].im, src1.re, src1.im, exp[i1].im, exp[i1].re); \
CMUL(z[i0].re, z[i1].im, src0.re, src0.im, exp[i0].im, exp[i0].re); \
} \
}
DECL_COMP_IMDCT(3)
DECL_COMP_IMDCT(5)
DECL_COMP_IMDCT(7)
DECL_COMP_IMDCT(9)
DECL_COMP_IMDCT(15)
#define DECL_COMP_MDCT(N) \
static void compound_mdct_##N##xM(AVTXContext *s, void *_dst, void *_src, \
ptrdiff_t stride) \
{ \
FFTSample *src = _src, *dst = _dst; \
FFTComplex *exp = s->exptab, tmp, fft##N##in[N]; \
const int m = s->m, len4 = N*m, len3 = len4 * 3, len8 = len4 >> 1; \
const int *in_map = s->pfatab, *out_map = in_map + N*m; \
void (*fftp)(FFTComplex *) = fft_dispatch[av_log2(m)]; \
\
stride /= sizeof(*dst); \
\
for (int i = 0; i < m; i++) { /* Folding and pre-reindexing */ \
for (int j = 0; j < N; j++) { \
const int k = in_map[i*N + j]; \
if (k < len4) { \
tmp.re = FOLD(-src[ len4 + k], src[1*len4 - 1 - k]); \
tmp.im = FOLD(-src[ len3 + k], -src[1*len3 - 1 - k]); \
} else { \
tmp.re = FOLD(-src[ len4 + k], -src[5*len4 - 1 - k]); \
tmp.im = FOLD( src[-len4 + k], -src[1*len3 - 1 - k]); \
} \
CMUL(fft##N##in[j].im, fft##N##in[j].re, tmp.re, tmp.im, \
exp[k >> 1].re, exp[k >> 1].im); \
} \
fft##N(s->tmp + s->revtab_c[i], fft##N##in, m); \
} \
\
for (int i = 0; i < N; i++) \
fftp(s->tmp + m*i); \
\
for (int i = 0; i < len8; i++) { \
const int i0 = len8 + i, i1 = len8 - i - 1; \
const int s0 = out_map[i0], s1 = out_map[i1]; \
FFTComplex src1 = { s->tmp[s1].re, s->tmp[s1].im }; \
FFTComplex src0 = { s->tmp[s0].re, s->tmp[s0].im }; \
\
CMUL(dst[2*i1*stride + stride], dst[2*i0*stride], src0.re, src0.im, \
exp[i0].im, exp[i0].re); \
CMUL(dst[2*i0*stride + stride], dst[2*i1*stride], src1.re, src1.im, \
exp[i1].im, exp[i1].re); \
} \
}
DECL_COMP_MDCT(3)
DECL_COMP_MDCT(5)
DECL_COMP_MDCT(7)
DECL_COMP_MDCT(9)
DECL_COMP_MDCT(15)
static void monolithic_imdct(AVTXContext *s, void *_dst, void *_src,
ptrdiff_t stride)
{
FFTComplex *z = _dst, *exp = s->exptab;
const int m = s->m, len8 = m >> 1;
const FFTSample *src = _src, *in1, *in2;
void (*fftp)(FFTComplex *) = fft_dispatch[av_log2(m)];
stride /= sizeof(*src);
in1 = src;
in2 = src + ((m*2) - 1) * stride;
for (int i = 0; i < m; i++) {
FFTComplex tmp = { in2[-2*i*stride], in1[2*i*stride] };
CMUL3(z[s->revtab_c[i]], tmp, exp[i]);
}
fftp(z);
for (int i = 0; i < len8; i++) {
const int i0 = len8 + i, i1 = len8 - i - 1;
FFTComplex src1 = { z[i1].im, z[i1].re };
FFTComplex src0 = { z[i0].im, z[i0].re };
CMUL(z[i1].re, z[i0].im, src1.re, src1.im, exp[i1].im, exp[i1].re);
CMUL(z[i0].re, z[i1].im, src0.re, src0.im, exp[i0].im, exp[i0].re);
}
}
static void monolithic_mdct(AVTXContext *s, void *_dst, void *_src,
ptrdiff_t stride)
{
FFTSample *src = _src, *dst = _dst;
FFTComplex *exp = s->exptab, tmp, *z = _dst;
const int m = s->m, len4 = m, len3 = len4 * 3, len8 = len4 >> 1;
void (*fftp)(FFTComplex *) = fft_dispatch[av_log2(m)];
stride /= sizeof(*dst);
for (int i = 0; i < m; i++) { /* Folding and pre-reindexing */
const int k = 2*i;
if (k < len4) {
tmp.re = FOLD(-src[ len4 + k], src[1*len4 - 1 - k]);
tmp.im = FOLD(-src[ len3 + k], -src[1*len3 - 1 - k]);
} else {
tmp.re = FOLD(-src[ len4 + k], -src[5*len4 - 1 - k]);
tmp.im = FOLD( src[-len4 + k], -src[1*len3 - 1 - k]);
}
CMUL(z[s->revtab_c[i]].im, z[s->revtab_c[i]].re, tmp.re, tmp.im,
exp[i].re, exp[i].im);
}
fftp(z);
for (int i = 0; i < len8; i++) {
const int i0 = len8 + i, i1 = len8 - i - 1;
FFTComplex src1 = { z[i1].re, z[i1].im };
FFTComplex src0 = { z[i0].re, z[i0].im };
CMUL(dst[2*i1*stride + stride], dst[2*i0*stride], src0.re, src0.im,
exp[i0].im, exp[i0].re);
CMUL(dst[2*i0*stride + stride], dst[2*i1*stride], src1.re, src1.im,
exp[i1].im, exp[i1].re);
}
}
static void naive_imdct(AVTXContext *s, void *_dst, void *_src,
ptrdiff_t stride)
{
int len = s->n;
int len2 = len*2;
FFTSample *src = _src;
FFTSample *dst = _dst;
double scale = s->scale;
const double phase = M_PI/(4.0*len2);
stride /= sizeof(*src);
for (int i = 0; i < len; i++) {
double sum_d = 0.0;
double sum_u = 0.0;
double i_d = phase * (4*len - 2*i - 1);
double i_u = phase * (3*len2 + 2*i + 1);
for (int j = 0; j < len2; j++) {
double a = (2 * j + 1);
double a_d = cos(a * i_d);
double a_u = cos(a * i_u);
double val = UNSCALE(src[j*stride]);
sum_d += a_d * val;
sum_u += a_u * val;
}
dst[i + 0] = RESCALE( sum_d*scale);
dst[i + len] = RESCALE(-sum_u*scale);
}
}
static void naive_mdct(AVTXContext *s, void *_dst, void *_src,
ptrdiff_t stride)
{
int len = s->n*2;
FFTSample *src = _src;
FFTSample *dst = _dst;
double scale = s->scale;
const double phase = M_PI/(4.0*len);
stride /= sizeof(*dst);
for (int i = 0; i < len; i++) {
double sum = 0.0;
for (int j = 0; j < len*2; j++) {
int a = (2*j + 1 + len) * (2*i + 1);
sum += UNSCALE(src[j]) * cos(a * phase);
}
dst[i*stride] = RESCALE(sum*scale);
}
}
static void full_imdct_wrapper_fn(AVTXContext *s, void *_dst, void *_src,
ptrdiff_t stride)
{
int len = s->m*s->n*4;
int len2 = len >> 1;
int len4 = len >> 2;
FFTSample *dst = _dst;
s->top_tx(s, dst + len4, _src, stride);
stride /= sizeof(*dst);
for (int i = 0; i < len4; i++) {
dst[ i*stride] = -dst[(len2 - i - 1)*stride];
dst[(len - i - 1)*stride] = dst[(len2 + i + 0)*stride];
}
}
static int gen_mdct_exptab(AVTXContext *s, int len4, double scale)
{
const double theta = (scale < 0 ? len4 : 0) + 1.0/8.0;
if (!(s->exptab = av_malloc_array(len4, sizeof(*s->exptab))))
return AVERROR(ENOMEM);
scale = sqrt(fabs(scale));
for (int i = 0; i < len4; i++) {
const double alpha = M_PI_2 * (i + theta) / len4;
s->exptab[i].re = RESCALE(cos(alpha) * scale);
s->exptab[i].im = RESCALE(sin(alpha) * scale);
}
return 0;
}
int TX_NAME(ff_tx_init_mdct_fft)(AVTXContext *s, av_tx_fn *tx,
enum AVTXType type, int inv, int len,
const void *scale, uint64_t flags)
{
const int is_mdct = ff_tx_type_is_mdct(type);
int err, l, n = 1, m = 1, max_ptwo = 1 << (FF_ARRAY_ELEMS(fft_dispatch) - 1);
if (is_mdct)
len >>= 1;
l = len;
#define CHECK_FACTOR(DST, FACTOR, SRC) \
if (DST == 1 && !(SRC % FACTOR)) { \
DST = FACTOR; \
SRC /= FACTOR; \
}
CHECK_FACTOR(n, 15, len)
CHECK_FACTOR(n, 9, len)
CHECK_FACTOR(n, 7, len)
CHECK_FACTOR(n, 5, len)
CHECK_FACTOR(n, 3, len)
#undef CHECK_FACTOR
/* len must be a power of two now */
if (!(len & (len - 1)) && len >= 2 && len <= max_ptwo) {
m = len;
len = 1;
}
s->n = n;
s->m = m;
s->inv = inv;
s->type = type;
s->flags = flags;
/* If we weren't able to split the length into factors we can handle,
* resort to using the naive and slow FT. This also filters out
* direct 3, 5 and 15 transforms as they're too niche. */
if (len > 1 || m == 1) {
if (is_mdct && (l & 1)) /* Odd (i)MDCTs are not supported yet */
return AVERROR(ENOSYS);
if (flags & AV_TX_INPLACE) /* Neither are in-place naive transforms */
return AVERROR(ENOSYS);
s->n = l;
s->m = 1;
*tx = naive_fft;
if (is_mdct) {
s->scale = *((SCALE_TYPE *)scale);
*tx = inv ? naive_imdct : naive_mdct;
if (inv && (flags & AV_TX_FULL_IMDCT)) {
s->top_tx = *tx;
*tx = full_imdct_wrapper_fn;
}
}
return 0;
}
if (n > 1 && m > 1) { /* 2D transform case */
if ((err = ff_tx_gen_compound_mapping(s)))
return err;
if (!(s->tmp = av_malloc(n*m*sizeof(*s->tmp))))
return AVERROR(ENOMEM);
if (!(m & (m - 1))) {
*tx = n == 3 ? compound_fft_3xM :
n == 5 ? compound_fft_5xM :
n == 7 ? compound_fft_7xM :
n == 9 ? compound_fft_9xM :
compound_fft_15xM;
if (is_mdct)
*tx = n == 3 ? inv ? compound_imdct_3xM : compound_mdct_3xM :
n == 5 ? inv ? compound_imdct_5xM : compound_mdct_5xM :
n == 7 ? inv ? compound_imdct_7xM : compound_mdct_7xM :
n == 9 ? inv ? compound_imdct_9xM : compound_mdct_9xM :
inv ? compound_imdct_15xM : compound_mdct_15xM;
}
} else { /* Direct transform case */
*tx = split_radix_fft;
if (is_mdct)
*tx = inv ? monolithic_imdct : monolithic_mdct;
}
if (n == 3 || n == 5 || n == 15)
init_cos_tabs(0);
else if (n == 7)
init_cos_tabs(1);
else if (n == 9)
init_cos_tabs(2);
if (m != 1 && !(m & (m - 1))) {
if ((err = ff_tx_gen_ptwo_revtab(s, n == 1 && !is_mdct && !(flags & AV_TX_INPLACE))))
return err;
if (flags & AV_TX_INPLACE) {
if (is_mdct) /* In-place MDCTs are not supported yet */
return AVERROR(ENOSYS);
if ((err = ff_tx_gen_ptwo_inplace_revtab_idx(s, s->revtab_c)))
return err;
}
for (int i = 4; i <= av_log2(m); i++)
init_cos_tabs(i);
}
if (is_mdct) {
if (inv && (flags & AV_TX_FULL_IMDCT)) {
s->top_tx = *tx;
*tx = full_imdct_wrapper_fn;
}
return gen_mdct_exptab(s, n*m, *((SCALE_TYPE *)scale));
}
return 0;
}