1 /* FFT and MDCT tests */
11 #define MUL16(a,b) ((a) * (b))
13 #define CMAC(pre, pim, are, aim, bre, bim) \
15 pre += (MUL16(are, bre) - MUL16(aim, bim));\
16 pim += (MUL16(are, bim) + MUL16(bre, aim));\
21 void fft_ref_init(int nbits, int inverse)
27 exptab = av_malloc((n / 2) * sizeof(FFTComplex));
29 for(i=0;i<(n/2);i++) {
30 alpha = 2 * M_PI * (float)i / (float)n;
40 void fft_ref(FFTComplex *tabr, FFTComplex *tab, int nbits)
43 float tmp_re, tmp_im, s, c;
53 k = (i * j) & (n - 1);
55 c = -exptab[k - n2].re;
56 s = -exptab[k - n2].im;
61 CMAC(tmp_re, tmp_im, c, s, q->re, q->im);
69 void imdct_ref(float *out, float *in, int n)
77 a = (2 * i + 1 + (n / 2)) * (2 * k + 1);
78 f = cos(M_PI * a / (double)(2 * n));
85 /* NOTE: no normalisation by 1 / N is done */
86 void mdct_ref(float *output, float *input, int n)
95 a = (2*M_PI*(2*i+1+n/2)*(2*k+1) / (4 * n));
96 s += input[i] * cos(a);
105 return (float)((random() & 0xffff) - 32768) / 32768.0;
108 int64_t gettime(void)
111 gettimeofday(&tv,NULL);
112 return (int64_t)tv.tv_sec * 1000000 + tv.tv_usec;
115 void check_diff(float *tab1, float *tab2, int n)
120 if (fabsf(tab1[i] - tab2[i]) >= 1e-3) {
121 printf("ERROR %d: %f %f\n",
122 i, tab1[i], tab2[i]);
130 printf("usage: fft-test [-h] [-s] [-i] [-n b]\n"
131 "-h print this help\n"
134 "-i inverse transform test\n"
135 "-n b set the transform size to 2^b\n"
142 int main(int argc, char **argv)
144 FFTComplex *tab, *tab1, *tab_ref;
145 FFTSample *tabtmp, *tab2;
150 FFTContext s1, *s = &s1;
151 MDCTContext m1, *m = &m1;
152 int fft_nbits, fft_size;
157 c = getopt(argc, argv, "hsimn:");
174 fft_nbits = atoi(optarg);
179 fft_size = 1 << fft_nbits;
180 tab = av_malloc(fft_size * sizeof(FFTComplex));
181 tab1 = av_malloc(fft_size * sizeof(FFTComplex));
182 tab_ref = av_malloc(fft_size * sizeof(FFTComplex));
183 tabtmp = av_malloc(fft_size / 2 * sizeof(FFTSample));
184 tab2 = av_malloc(fft_size * sizeof(FFTSample));
191 ff_mdct_init(m, fft_nbits, do_inverse);
197 fft_init(s, fft_nbits, do_inverse);
198 fft_ref_init(fft_nbits, do_inverse);
200 printf(" %d test\n", fft_size);
202 /* generate random data */
204 for(i=0;i<fft_size;i++) {
205 tab1[i].re = frandom();
206 tab1[i].im = frandom();
209 /* checking result */
210 printf("Checking...\n");
214 imdct_ref((float *)tab_ref, (float *)tab1, fft_size);
215 ff_imdct_calc(m, tab2, (float *)tab1, tabtmp);
216 check_diff((float *)tab_ref, tab2, fft_size);
218 mdct_ref((float *)tab_ref, (float *)tab1, fft_size);
220 ff_mdct_calc(m, tab2, (float *)tab1, tabtmp);
222 check_diff((float *)tab_ref, tab2, fft_size / 2);
225 memcpy(tab, tab1, fft_size * sizeof(FFTComplex));
229 fft_ref(tab_ref, tab1, fft_nbits);
230 check_diff((float *)tab_ref, (float *)tab, fft_size * 2);
233 /* do a speed test */
236 int64_t time_start, duration;
239 printf("Speed test...\n");
240 /* we measure during about 1 seconds */
243 time_start = gettime();
244 for(it=0;it<nb_its;it++) {
247 ff_imdct_calc(m, (float *)tab, (float *)tab1, tabtmp);
249 ff_mdct_calc(m, (float *)tab, (float *)tab1, tabtmp);
252 memcpy(tab, tab1, fft_size * sizeof(FFTComplex));
256 duration = gettime() - time_start;
257 if (duration >= 1000000)
261 printf("time: %0.1f us/transform [total time=%0.2f s its=%d]\n",
262 (double)duration / nb_its,
263 (double)duration / 1000000.0,