1 /* DCT test. (c) 2001 Gerard Lantau.
2 Started from sample code by Juan J. Sierralta P.
15 /* reference fdct/idct */
16 extern void fdct(DCTELEM *block);
17 extern void idct(DCTELEM *block);
18 extern void init_fdct();
20 extern void j_rev_dct(DCTELEM *data);
21 extern void ff_mmx_idct(DCTELEM *data);
22 extern void ff_mmxext_idct(DCTELEM *data);
24 #define AANSCALE_BITS 12
25 static const unsigned short aanscales[64] = {
26 /* precomputed values scaled up by 14 bits */
27 16384, 22725, 21407, 19266, 16384, 12873, 8867, 4520,
28 22725, 31521, 29692, 26722, 22725, 17855, 12299, 6270,
29 21407, 29692, 27969, 25172, 21407, 16819, 11585, 5906,
30 19266, 26722, 25172, 22654, 19266, 15137, 10426, 5315,
31 16384, 22725, 21407, 19266, 16384, 12873, 8867, 4520,
32 12873, 17855, 16819, 15137, 12873, 10114, 6967, 3552,
33 8867, 12299, 11585, 10426, 8867, 6967, 4799, 2446,
34 4520, 6270, 5906, 5315, 4520, 3552, 2446, 1247
40 gettimeofday(&tv,NULL);
41 return (INT64)tv.tv_sec * 1000000 + tv.tv_usec;
45 #define NB_ITS_SPEED 50000
47 static short idct_mmx_perm[64];
49 void idct_mmx_init(void)
53 /* the mmx/mmxext idct uses a reordered input, so we patch scan tables */
54 for (i = 0; i < 64; i++) {
55 idct_mmx_perm[i] = (i & 0x38) | ((i & 6) >> 1) | ((i & 1) << 2);
59 static DCTELEM block[64] __attribute__ ((aligned (8)));
60 static DCTELEM block1[64] __attribute__ ((aligned (8)));
62 void dct_error(const char *name, int is_idct,
63 void (*fdct_func)(DCTELEM *block),
64 void (*fdct_ref)(DCTELEM *block))
68 INT64 err2, ti, ti1, it1;
74 for(it=0;it<NB_ITS;it++) {
76 block1[i] = random() % 256;
78 /* for idct test, generate inverse idct data */
82 if (fdct_func == ff_mmx_idct ||
83 fdct_func == j_rev_dct) {
85 block[idct_mmx_perm[i]] = block1[i];
87 memcpy(block, block1, sizeof(DCTELEM) * 64);
91 emms(); /* for ff_mmx_idct */
93 if (fdct_func == jpeg_fdct_ifast) {
95 scale = (1 << (AANSCALE_BITS + 11)) / aanscales[i];
96 block[i] = (block[i] * scale) >> AANSCALE_BITS;
103 v = abs(block[i] - block1[i]);
109 printf("%s %s: err_inf=%d err2=%0.2f\n",
110 is_idct ? "IDCT" : "DCT",
111 name, err_inf, (double)err2 / NB_ITS / 64.0);
115 block1[i] = 255 - 63 + i;
117 /* for idct test, generate inverse idct data */
120 if (fdct_func == ff_mmx_idct ||
121 fdct_func == j_rev_dct) {
123 block[idct_mmx_perm[i]] = block1[i];
129 for(it=0;it<NB_ITS_SPEED;it++) {
130 memcpy(block, block1, sizeof(DCTELEM) * 64);
134 ti1 = gettime() - ti;
135 } while (ti1 < 1000000);
138 printf("%s %s: %0.1f kdct/s\n",
139 is_idct ? "IDCT" : "DCT",
140 name, (double)it1 * 1000.0 / (double)ti1);
145 printf("dct-test [-i]\n"
146 "test DCT implementations\n");
150 int main(int argc, char **argv)
159 c = getopt(argc, argv, "ih");
172 printf("ffmpeg DCT/IDCT test\n");
175 dct_error("REF", 0, fdct, fdct); /* only to verify code ! */
176 dct_error("AAN", 0, jpeg_fdct_ifast, fdct);
177 dct_error("MMX", 0, fdct_mmx, fdct);
179 dct_error("REF", 1, idct, idct);
180 dct_error("INT", 1, j_rev_dct, idct);
181 dct_error("MMX", 1, ff_mmx_idct, idct);
182 // dct_error("MMX", 1, ff_mmxext_idct, idct);