/* * (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 "config.h" #ifndef AVFFT #define AVFFT 0 #endif #include <math.h> #if HAVE_UNISTD_H #include <unistd.h> #endif #include <stdio.h> #include <stdlib.h> #include <string.h> #include "libavutil/cpu.h" #include "libavutil/lfg.h" #include "libavutil/log.h" #include "libavutil/mathematics.h" #include "libavutil/time.h" #if AVFFT #include "libavcodec/avfft.h" #else #include "libavcodec/fft.h" #endif #if FFT_FLOAT #include "libavcodec/dct.h" #include "libavcodec/rdft.h" #endif /* 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 FFT_FLOAT || AVFFT #define RANGE 1.0 #define REF_SCALE(x, bits) (x) #define FMT "%10.6f" #elif FFT_FIXED_32 #define RANGE 8388608 #define REF_SCALE(x, bits) (x) #define FMT "%6d" #else #define RANGE 16384 #define REF_SCALE(x, bits) ((x) / (1 << (bits))) #define FMT "%6d" #endif static struct { float re, im; } *exptab; static int fft_ref_init(int nbits, int inverse) { int i, n = 1 << nbits; exptab = av_malloc_array((n / 2), sizeof(*exptab)); if (!exptab) return AVERROR(ENOMEM); for (i = 0; i < (n / 2); i++) { double alpha = 2 * M_PI * (float) i / (float) n; double c1 = cos(alpha), s1 = sin(alpha); if (!inverse) s1 = -s1; exptab[i].re = c1; exptab[i].im = s1; } return 0; } static void fft_ref(FFTComplex *tabr, FFTComplex *tab, int nbits) { int i, j; int n = 1 << nbits; int n2 = n >> 1; for (i = 0; i < n; i++) { double tmp_re = 0, tmp_im = 0; FFTComplex *q = tab; for (j = 0; j < n; j++) { double s, c; int 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); } } #if CONFIG_MDCT static void imdct_ref(FFTSample *out, FFTSample *in, int nbits) { int i, k, n = 1 << nbits; for (i = 0; i < n; i++) { double sum = 0; for (k = 0; k < n / 2; k++) { int a = (2 * i + 1 + (n / 2)) * (2 * k + 1); double 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 i, k, n = 1 << nbits; /* do it by hand */ for (k = 0; k < n / 2; k++) { double s = 0; for (i = 0; i < n; i++) { double 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); } } #endif /* CONFIG_MDCT */ #if FFT_FLOAT #if CONFIG_DCT static void idct_ref(FFTSample *output, FFTSample *input, int nbits) { int i, k, n = 1 << nbits; /* do it by hand */ for (i = 0; i < n; i++) { double s = 0.5 * input[0]; for (k = 1; k < n; k++) { double 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 i, k, n = 1 << nbits; /* do it by hand */ for (k = 0; k < n; k++) { double s = 0; for (i = 0; i < n; i++) { double a = M_PI * k * (i + 0.5) / n; s += input[i] * cos(a); } output[k] = s; } } #endif /* CONFIG_DCT */ #endif /* FFT_FLOAT */ 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, err = 0; double error = 0, max = 0; for (i = 0; i < n; i++) { double e = fabs(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 inline void fft_init(FFTContext **s, int nbits, int inverse) { #if AVFFT *s = av_fft_init(nbits, inverse); #else ff_fft_init(*s, nbits, inverse); #endif } static inline void mdct_init(FFTContext **s, int nbits, int inverse, double scale) { #if AVFFT *s = av_mdct_init(nbits, inverse, scale); #else ff_mdct_init(*s, nbits, inverse, scale); #endif } static inline void mdct_calc(FFTContext *s, FFTSample *output, const FFTSample *input) { #if AVFFT av_mdct_calc(s, output, input); #else s->mdct_calc(s, output, input); #endif } static inline void imdct_calc(struct FFTContext *s, FFTSample *output, const FFTSample *input) { #if AVFFT av_imdct_calc(s, output, input); #else s->imdct_calc(s, output, input); #endif } static inline void fft_permute(FFTContext *s, FFTComplex *z) { #if AVFFT av_fft_permute(s, z); #else s->fft_permute(s, z); #endif } static inline void fft_calc(FFTContext *s, FFTComplex *z) { #if AVFFT av_fft_calc(s, z); #else s->fft_calc(s, z); #endif } static inline void mdct_end(FFTContext *s) { #if AVFFT av_mdct_end(s); #else ff_mdct_end(s); #endif } static inline void fft_end(FFTContext *s) { #if AVFFT av_fft_end(s); #else ff_fft_end(s); #endif } #if FFT_FLOAT static inline void rdft_init(RDFTContext **r, int nbits, enum RDFTransformType trans) { #if AVFFT *r = av_rdft_init(nbits, trans); #else ff_rdft_init(*r, nbits, trans); #endif } static inline void dct_init(DCTContext **d, int nbits, enum DCTTransformType trans) { #if AVFFT *d = av_dct_init(nbits, trans); #else ff_dct_init(*d, nbits, trans); #endif } static inline void rdft_calc(RDFTContext *r, FFTSample *tab) { #if AVFFT av_rdft_calc(r, tab); #else r->rdft_calc(r, tab); #endif } static inline void dct_calc(DCTContext *d, FFTSample *data) { #if AVFFT av_dct_calc(d, data); #else d->dct_calc(d, data); #endif } static inline void rdft_end(RDFTContext *r) { #if AVFFT av_rdft_end(r); #else ff_rdft_end(r); #endif } static inline void dct_end(DCTContext *d) { #if AVFFT av_dct_end(d); #else ff_dct_end(d); #endif } #endif /* FFT_FLOAT */ 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; enum tf_transform transform = TRANSFORM_FFT; FFTContext *m, *s; #if FFT_FLOAT RDFTContext *r; DCTContext *d; #endif /* FFT_FLOAT */ int it, i, err = 1; int do_speed = 0, do_inverse = 0; int fft_nbits = 9, fft_size; double scale = 1.0; AVLFG prng; #if !AVFFT s = av_mallocz(sizeof(*s)); m = av_mallocz(sizeof(*m)); #endif #if !AVFFT && FFT_FLOAT r = av_mallocz(sizeof(*r)); d = av_mallocz(sizeof(*d)); #endif av_lfg_init(&prng, 1); for (;;) { int 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': { unsigned 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_array(fft_size, sizeof(FFTComplex)); tab1 = av_malloc_array(fft_size, sizeof(FFTComplex)); tab_ref = av_malloc_array(fft_size, sizeof(FFTComplex)); tab2 = av_malloc_array(fft_size, sizeof(FFTSample)); if (!(tab && tab1 && tab_ref && tab2)) goto cleanup; switch (transform) { #if CONFIG_MDCT 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"); mdct_init(&m, fft_nbits, do_inverse, scale); break; #endif /* CONFIG_MDCT */ case TRANSFORM_FFT: if (do_inverse) av_log(NULL, AV_LOG_INFO, "IFFT"); else av_log(NULL, AV_LOG_INFO, "FFT"); fft_init(&s, fft_nbits, do_inverse); if ((err = fft_ref_init(fft_nbits, do_inverse)) < 0) goto cleanup; break; #if FFT_FLOAT # if CONFIG_RDFT case TRANSFORM_RDFT: if (do_inverse) av_log(NULL, AV_LOG_INFO, "IDFT_C2R"); else av_log(NULL, AV_LOG_INFO, "DFT_R2C"); rdft_init(&r, fft_nbits, do_inverse ? IDFT_C2R : DFT_R2C); if ((err = fft_ref_init(fft_nbits, do_inverse)) < 0) goto cleanup; break; # endif /* CONFIG_RDFT */ # if CONFIG_DCT case TRANSFORM_DCT: if (do_inverse) av_log(NULL, AV_LOG_INFO, "DCT_III"); else av_log(NULL, AV_LOG_INFO, "DCT_II"); dct_init(&d, fft_nbits, do_inverse ? DCT_III : DCT_II); break; # endif /* CONFIG_DCT */ #endif /* FFT_FLOAT */ default: av_log(NULL, AV_LOG_ERROR, "Requested transform not supported\n"); goto cleanup; } 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) { #if CONFIG_MDCT case TRANSFORM_MDCT: if (do_inverse) { imdct_ref(&tab_ref->re, &tab1->re, fft_nbits); imdct_calc(m, tab2, &tab1->re); err = check_diff(&tab_ref->re, tab2, fft_size, scale); } else { mdct_ref(&tab_ref->re, &tab1->re, fft_nbits); mdct_calc(m, tab2, &tab1->re); err = check_diff(&tab_ref->re, tab2, fft_size / 2, scale); } break; #endif /* CONFIG_MDCT */ case TRANSFORM_FFT: memcpy(tab, tab1, fft_size * sizeof(FFTComplex)); fft_permute(s, tab); fft_calc(s, tab); fft_ref(tab_ref, tab1, fft_nbits); err = check_diff(&tab_ref->re, &tab->re, fft_size * 2, 1.0); break; #if FFT_FLOAT #if CONFIG_RDFT case TRANSFORM_RDFT: { int 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; 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(&tab_ref->re, &tab->re, fft_size * 2, 0.5); } else { for (i = 0; i < fft_size; i++) { tab2[i] = tab1[i].re; tab1[i].im = 0; } rdft_calc(r, tab2); fft_ref(tab_ref, tab1, fft_nbits); tab_ref[0].im = tab_ref[fft_size_2].re; err = check_diff(&tab_ref->re, tab2, fft_size, 1.0); } break; } #endif /* CONFIG_RDFT */ #if CONFIG_DCT case TRANSFORM_DCT: memcpy(tab, tab1, fft_size * sizeof(FFTComplex)); dct_calc(d, &tab->re); if (do_inverse) idct_ref(&tab_ref->re, &tab1->re, fft_nbits); else dct_ref(&tab_ref->re, &tab1->re, fft_nbits); err = check_diff(&tab_ref->re, &tab->re, fft_size, 1.0); break; #endif /* CONFIG_DCT */ #endif /* FFT_FLOAT */ } /* 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_relative(); for (it = 0; it < nb_its; it++) { switch (transform) { case TRANSFORM_MDCT: if (do_inverse) imdct_calc(m, &tab->re, &tab1->re); else mdct_calc(m, &tab->re, &tab1->re); break; case TRANSFORM_FFT: memcpy(tab, tab1, fft_size * sizeof(FFTComplex)); fft_calc(s, tab); break; #if FFT_FLOAT case TRANSFORM_RDFT: memcpy(tab2, tab1, fft_size * sizeof(FFTSample)); rdft_calc(r, tab2); break; case TRANSFORM_DCT: memcpy(tab2, tab1, fft_size * sizeof(FFTSample)); dct_calc(d, tab2); break; #endif /* FFT_FLOAT */ } } duration = av_gettime_relative() - 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) { #if CONFIG_MDCT case TRANSFORM_MDCT: mdct_end(m); break; #endif /* CONFIG_MDCT */ case TRANSFORM_FFT: fft_end(s); break; #if FFT_FLOAT # if CONFIG_RDFT case TRANSFORM_RDFT: rdft_end(r); break; # endif /* CONFIG_RDFT */ # if CONFIG_DCT case TRANSFORM_DCT: dct_end(d); break; # endif /* CONFIG_DCT */ #endif /* FFT_FLOAT */ } cleanup: av_free(tab); av_free(tab1); av_free(tab2); av_free(tab_ref); av_free(exptab); #if !AVFFT av_free(s); av_free(m); #endif #if !AVFFT && FFT_FLOAT av_free(r); av_free(d); #endif if (err) printf("Error: %d.\n", err); return !!err; }