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/*
* (c) 2002 Fabrice Bellard
*
* 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
*/
/**
* @file
* FFT and MDCT tests.
*/
#include "libavutil/cpu.h"
#include "libavutil/mathematics.h"
#include "libavutil/lfg.h"
#include "libavutil/log.h"
#include "libavutil/time.h"
#include "fft.h"
#if CONFIG_FFT_FLOAT
#include "dct.h"
#include "rdft.h"
#endif
#include <math.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <stdlib.h>
#include <string.h>
/* reference fft */
#define MUL16(a,b) ((a) * (b))
#define CMAC(pre, pim, are, aim, bre, bim) \
{\
pre += (MUL16(are, bre) - MUL16(aim, bim));\
pim += (MUL16(are, bim) + MUL16(bre, aim));\
}
#if CONFIG_FFT_FLOAT
# define RANGE 1.0
# define REF_SCALE(x, bits) (x)
# define FMT "%10.6f"
#else
# define RANGE 16384
# define REF_SCALE(x, bits) ((x) / (1<<(bits)))
# define FMT "%6d"
#endif
struct {
float re, im;
} *exptab;
static void fft_ref_init(int nbits, int inverse)
{
int n, i;
double c1, s1, alpha;
n = 1 << nbits;
exptab = av_malloc((n / 2) * sizeof(*exptab));
for (i = 0; i < (n/2); i++) {
alpha = 2 * M_PI * (float)i / (float)n;
c1 = cos(alpha);
s1 = sin(alpha);
if (!inverse)
s1 = -s1;
exptab[i].re = c1;
exptab[i].im = s1;
}
}
static void fft_ref(FFTComplex *tabr, FFTComplex *tab, int nbits)
{
int n, i, j, k, n2;
double tmp_re, tmp_im, s, c;
FFTComplex *q;
n = 1 << nbits;
n2 = n >> 1;
for (i = 0; i < n; i++) {
tmp_re = 0;
tmp_im = 0;
q = tab;
for (j = 0; j < n; j++) {
k = (i * j) & (n - 1);
if (k >= n2) {
c = -exptab[k - n2].re;
s = -exptab[k - n2].im;
} else {
c = exptab[k].re;
s = exptab[k].im;
}
CMAC(tmp_re, tmp_im, c, s, q->re, q->im);
q++;
}
tabr[i].re = REF_SCALE(tmp_re, nbits);
tabr[i].im = REF_SCALE(tmp_im, nbits);
}
}
static void imdct_ref(FFTSample *out, FFTSample *in, int nbits)
{
int n = 1<<nbits;
int k, i, a;
double sum, f;
for (i = 0; i < n; i++) {
sum = 0;
for (k = 0; k < n/2; k++) {
a = (2 * i + 1 + (n / 2)) * (2 * k + 1);
f = cos(M_PI * a / (double)(2 * n));
sum += f * in[k];
}
out[i] = REF_SCALE(-sum, nbits - 2);
}
}
/* NOTE: no normalisation by 1 / N is done */
static void mdct_ref(FFTSample *output, FFTSample *input, int nbits)
{
int n = 1<<nbits;
int k, i;
double a, s;
/* do it by hand */
for (k = 0; k < n/2; k++) {
s = 0;
for (i = 0; i < n; i++) {
a = (2*M_PI*(2*i+1+n/2)*(2*k+1) / (4 * n));
s += input[i] * cos(a);
}
output[k] = REF_SCALE(s, nbits - 1);
}
}
#if CONFIG_FFT_FLOAT
static void idct_ref(FFTSample *output, FFTSample *input, int nbits)
{
int n = 1<<nbits;
int k, i;
double a, s;
/* do it by hand */
for (i = 0; i < n; i++) {
s = 0.5 * input[0];
for (k = 1; k < n; k++) {
a = M_PI*k*(i+0.5) / n;
s += input[k] * cos(a);
}
output[i] = 2 * s / n;
}
}
static void dct_ref(FFTSample *output, FFTSample *input, int nbits)
{
int n = 1<<nbits;
int k, i;
double a, s;
/* do it by hand */
for (k = 0; k < n; k++) {
s = 0;
for (i = 0; i < n; i++) {
a = M_PI*k*(i+0.5) / n;
s += input[i] * cos(a);
}
output[k] = s;
}
}
#endif
static FFTSample frandom(AVLFG *prng)
{
return (int16_t)av_lfg_get(prng) / 32768.0 * RANGE;
}
static int check_diff(FFTSample *tab1, FFTSample *tab2, int n, double scale)
{
int i;
double max= 0;
double error= 0;
int err = 0;
for (i = 0; i < n; i++) {
double e = fabsf(tab1[i] - (tab2[i] / scale)) / RANGE;
if (e >= 1e-3) {
av_log(NULL, AV_LOG_ERROR, "ERROR %5d: "FMT" "FMT"\n",
i, tab1[i], tab2[i]);
err = 1;
}
error+= e*e;
if(e>max) max= e;
}
av_log(NULL, AV_LOG_INFO, "max:%f e:%g\n", max, sqrt(error)/n);
return err;
}
static void help(void)
{
av_log(NULL, AV_LOG_INFO,"usage: fft-test [-h] [-s] [-i] [-n b]\n"
"-h print this help\n"
"-s speed test\n"
"-m (I)MDCT test\n"
"-d (I)DCT test\n"
"-r (I)RDFT test\n"
"-i inverse transform test\n"
"-n b set the transform size to 2^b\n"
"-f x set scale factor for output data of (I)MDCT to x\n"
);
}
enum tf_transform {
TRANSFORM_FFT,
TRANSFORM_MDCT,
TRANSFORM_RDFT,
TRANSFORM_DCT,
};
#if !HAVE_GETOPT
#include "compat/getopt.c"
#endif
int main(int argc, char **argv)
{
FFTComplex *tab, *tab1, *tab_ref;
FFTSample *tab2;
int it, i, c;
int cpuflags;
int do_speed = 0;
int err = 1;
enum tf_transform transform = TRANSFORM_FFT;
int do_inverse = 0;
FFTContext s1, *s = &s1;
FFTContext m1, *m = &m1;
#if CONFIG_FFT_FLOAT
RDFTContext r1, *r = &r1;
DCTContext d1, *d = &d1;
int fft_size_2;
#endif
int fft_nbits, fft_size;
double scale = 1.0;
AVLFG prng;
av_lfg_init(&prng, 1);
fft_nbits = 9;
for(;;) {
c = getopt(argc, argv, "hsimrdn:f:c:");
if (c == -1)
break;
switch(c) {
case 'h':
help();
return 1;
case 's':
do_speed = 1;
break;
case 'i':
do_inverse = 1;
break;
case 'm':
transform = TRANSFORM_MDCT;
break;
case 'r':
transform = TRANSFORM_RDFT;
break;
case 'd':
transform = TRANSFORM_DCT;
break;
case 'n':
fft_nbits = atoi(optarg);
break;
case 'f':
scale = atof(optarg);
break;
case 'c':
cpuflags = av_get_cpu_flags();
if (av_parse_cpu_caps(&cpuflags, optarg) < 0)
return 1;
av_force_cpu_flags(cpuflags);
break;
}
}
fft_size = 1 << fft_nbits;
tab = av_malloc(fft_size * sizeof(FFTComplex));
tab1 = av_malloc(fft_size * sizeof(FFTComplex));
tab_ref = av_malloc(fft_size * sizeof(FFTComplex));
tab2 = av_malloc(fft_size * sizeof(FFTSample));
switch (transform) {
case TRANSFORM_MDCT:
av_log(NULL, AV_LOG_INFO,"Scale factor is set to %f\n", scale);
if (do_inverse)
av_log(NULL, AV_LOG_INFO,"IMDCT");
else
av_log(NULL, AV_LOG_INFO,"MDCT");
ff_mdct_init(m, fft_nbits, do_inverse, scale);
break;
case TRANSFORM_FFT:
if (do_inverse)
av_log(NULL, AV_LOG_INFO,"IFFT");
else
av_log(NULL, AV_LOG_INFO,"FFT");
ff_fft_init(s, fft_nbits, do_inverse);
fft_ref_init(fft_nbits, do_inverse);
break;
#if CONFIG_FFT_FLOAT
case TRANSFORM_RDFT:
if (do_inverse)
av_log(NULL, AV_LOG_INFO,"IDFT_C2R");
else
av_log(NULL, AV_LOG_INFO,"DFT_R2C");
ff_rdft_init(r, fft_nbits, do_inverse ? IDFT_C2R : DFT_R2C);
fft_ref_init(fft_nbits, do_inverse);
break;
case TRANSFORM_DCT:
if (do_inverse)
av_log(NULL, AV_LOG_INFO,"DCT_III");
else
av_log(NULL, AV_LOG_INFO,"DCT_II");
ff_dct_init(d, fft_nbits, do_inverse ? DCT_III : DCT_II);
break;
#endif
default:
av_log(NULL, AV_LOG_ERROR, "Requested transform not supported\n");
return 1;
}
av_log(NULL, AV_LOG_INFO," %d test\n", fft_size);
/* generate random data */
for (i = 0; i < fft_size; i++) {
tab1[i].re = frandom(&prng);
tab1[i].im = frandom(&prng);
}
/* checking result */
av_log(NULL, AV_LOG_INFO,"Checking...\n");
switch (transform) {
case TRANSFORM_MDCT:
if (do_inverse) {
imdct_ref((FFTSample *)tab_ref, (FFTSample *)tab1, fft_nbits);
m->imdct_calc(m, tab2, (FFTSample *)tab1);
err = check_diff((FFTSample *)tab_ref, tab2, fft_size, scale);
} else {
mdct_ref((FFTSample *)tab_ref, (FFTSample *)tab1, fft_nbits);
m->mdct_calc(m, tab2, (FFTSample *)tab1);
err = check_diff((FFTSample *)tab_ref, tab2, fft_size / 2, scale);
}
break;
case TRANSFORM_FFT:
memcpy(tab, tab1, fft_size * sizeof(FFTComplex));
s->fft_permute(s, tab);
s->fft_calc(s, tab);
fft_ref(tab_ref, tab1, fft_nbits);
err = check_diff((FFTSample *)tab_ref, (FFTSample *)tab, fft_size * 2, 1.0);
break;
#if CONFIG_FFT_FLOAT
case TRANSFORM_RDFT:
fft_size_2 = fft_size >> 1;
if (do_inverse) {
tab1[ 0].im = 0;
tab1[fft_size_2].im = 0;
for (i = 1; i < fft_size_2; i++) {
tab1[fft_size_2+i].re = tab1[fft_size_2-i].re;
tab1[fft_size_2+i].im = -tab1[fft_size_2-i].im;
}
memcpy(tab2, tab1, fft_size * sizeof(FFTSample));
tab2[1] = tab1[fft_size_2].re;
r->rdft_calc(r, tab2);
fft_ref(tab_ref, tab1, fft_nbits);
for (i = 0; i < fft_size; i++) {
tab[i].re = tab2[i];
tab[i].im = 0;
}
err = check_diff((float *)tab_ref, (float *)tab, fft_size * 2, 0.5);
} else {
for (i = 0; i < fft_size; i++) {
tab2[i] = tab1[i].re;
tab1[i].im = 0;
}
r->rdft_calc(r, tab2);
fft_ref(tab_ref, tab1, fft_nbits);
tab_ref[0].im = tab_ref[fft_size_2].re;
err = check_diff((float *)tab_ref, (float *)tab2, fft_size, 1.0);
}
break;
case TRANSFORM_DCT:
memcpy(tab, tab1, fft_size * sizeof(FFTComplex));
d->dct_calc(d, (FFTSample *)tab);
if (do_inverse) {
idct_ref((FFTSample*)tab_ref, (FFTSample *)tab1, fft_nbits);
} else {
dct_ref((FFTSample*)tab_ref, (FFTSample *)tab1, fft_nbits);
}
err = check_diff((float *)tab_ref, (float *)tab, fft_size, 1.0);
break;
#endif
}
/* do a speed test */
if (do_speed) {
int64_t time_start, duration;
int nb_its;
av_log(NULL, AV_LOG_INFO,"Speed test...\n");
/* we measure during about 1 seconds */
nb_its = 1;
for(;;) {
time_start = av_gettime();
for (it = 0; it < nb_its; it++) {
switch (transform) {
case TRANSFORM_MDCT:
if (do_inverse) {
m->imdct_calc(m, (FFTSample *)tab, (FFTSample *)tab1);
} else {
m->mdct_calc(m, (FFTSample *)tab, (FFTSample *)tab1);
}
break;
case TRANSFORM_FFT:
memcpy(tab, tab1, fft_size * sizeof(FFTComplex));
s->fft_calc(s, tab);
break;
#if CONFIG_FFT_FLOAT
case TRANSFORM_RDFT:
memcpy(tab2, tab1, fft_size * sizeof(FFTSample));
r->rdft_calc(r, tab2);
break;
case TRANSFORM_DCT:
memcpy(tab2, tab1, fft_size * sizeof(FFTSample));
d->dct_calc(d, tab2);
break;
#endif
}
}
duration = av_gettime() - time_start;
if (duration >= 1000000)
break;
nb_its *= 2;
}
av_log(NULL, AV_LOG_INFO,"time: %0.1f us/transform [total time=%0.2f s its=%d]\n",
(double)duration / nb_its,
(double)duration / 1000000.0,
nb_its);
}
switch (transform) {
case TRANSFORM_MDCT:
ff_mdct_end(m);
break;
case TRANSFORM_FFT:
ff_fft_end(s);
break;
#if CONFIG_FFT_FLOAT
case TRANSFORM_RDFT:
ff_rdft_end(r);
break;
case TRANSFORM_DCT:
ff_dct_end(d);
break;
#endif
}
av_free(tab);
av_free(tab1);
av_free(tab2);
av_free(tab_ref);
av_free(exptab);
return err;
}
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