FFmpeg  4.0
dct.c
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1 /*
2  * (c) 2001 Fabrice Bellard
3  * 2007 Marc Hoffman <marc.hoffman@analog.com>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * DCT test (c) 2001 Fabrice Bellard
25  * Started from sample code by Juan J. Sierralta P.
26  */
27 
28 #include "config.h"
29 #include <stdlib.h>
30 #include <stdio.h>
31 #include <string.h>
32 #if HAVE_UNISTD_H
33 #include <unistd.h>
34 #endif
35 #include <math.h>
36 
37 #include "libavutil/cpu.h"
38 #include "libavutil/common.h"
39 #include "libavutil/internal.h"
40 #include "libavutil/lfg.h"
41 #include "libavutil/time.h"
42 
43 #include "libavcodec/dct.h"
44 #include "libavcodec/idctdsp.h"
45 #include "libavcodec/simple_idct.h"
46 #include "libavcodec/xvididct.h"
47 #include "libavcodec/aandcttab.h"
48 #include "libavcodec/faandct.h"
49 #include "libavcodec/faanidct.h"
50 #include "libavcodec/dctref.h"
51 
52 struct algo {
53  const char *name;
54  void (*func)(int16_t *block);
56  int cpu_flag;
57  int nonspec;
58 };
59 
60 static const struct algo fdct_tab[] = {
61  { "REF-DBL", ff_ref_fdct, FF_IDCT_PERM_NONE },
62  { "IJG-AAN-INT", ff_fdct_ifast, FF_IDCT_PERM_NONE },
63  { "IJG-LLM-INT", ff_jpeg_fdct_islow_8, FF_IDCT_PERM_NONE },
64 #if CONFIG_FAANDCT
65  { "FAAN", ff_faandct, FF_IDCT_PERM_NONE },
66 #endif /* CONFIG_FAANDCT */
67 };
68 
69 static void ff_prores_idct_wrap(int16_t *dst){
70  LOCAL_ALIGNED(16, int16_t, qmat, [64]);
71  int i;
72 
73  for(i=0; i<64; i++){
74  qmat[i]=4;
75  }
76  ff_prores_idct(dst, qmat);
77  for(i=0; i<64; i++) {
78  dst[i] -= 512;
79  }
80 }
81 
82 static const struct algo idct_tab[] = {
83  { "REF-DBL", ff_ref_idct, FF_IDCT_PERM_NONE },
85  { "SIMPLE-C", ff_simple_idct_int16_8bit, FF_IDCT_PERM_NONE },
86  { "SIMPLE-C10", ff_simple_idct_int16_10bit, FF_IDCT_PERM_NONE },
87  { "SIMPLE-C12", ff_simple_idct_int16_12bit, FF_IDCT_PERM_NONE, 0, 1 },
88  { "PR-C", ff_prores_idct_wrap, FF_IDCT_PERM_NONE, 0, 1 },
89 #if CONFIG_FAANIDCT
90  { "FAANI", ff_faanidct, FF_IDCT_PERM_NONE },
91 #endif /* CONFIG_FAANIDCT */
92 #if CONFIG_MPEG4_DECODER
93  { "XVID", ff_xvid_idct, FF_IDCT_PERM_NONE, 0, 1 },
94 #endif /* CONFIG_MPEG4_DECODER */
95 };
96 
97 #if ARCH_AARCH64
98 #include "aarch64/dct.c"
99 #elif ARCH_ARM
100 #include "arm/dct.c"
101 #elif ARCH_PPC
102 #include "ppc/dct.c"
103 #elif ARCH_X86
104 #include "x86/dct.c"
105 #else
106 static const struct algo fdct_tab_arch[] = { { 0 } };
107 static const struct algo idct_tab_arch[] = { { 0 } };
108 #endif
109 
110 #define AANSCALE_BITS 12
111 
112 #define NB_ITS 20000
113 #define NB_ITS_SPEED 50000
114 
115 DECLARE_ALIGNED(16, static int16_t, block)[64];
116 DECLARE_ALIGNED(8, static int16_t, block1)[64];
117 
118 static void init_block(int16_t block[64], int test, int is_idct, AVLFG *prng, int vals)
119 {
120  int i, j;
121 
122  memset(block, 0, 64 * sizeof(*block));
123 
124  switch (test) {
125  case 0:
126  for (i = 0; i < 64; i++)
127  block[i] = (av_lfg_get(prng) % (2*vals)) -vals;
128  if (is_idct) {
129  ff_ref_fdct(block);
130  for (i = 0; i < 64; i++)
131  block[i] >>= 3;
132  }
133  break;
134  case 1:
135  j = av_lfg_get(prng) % 10 + 1;
136  for (i = 0; i < j; i++) {
137  int idx = av_lfg_get(prng) % 64;
138  block[idx] = av_lfg_get(prng) % (2*vals) -vals;
139  }
140  break;
141  case 2:
142  block[ 0] = av_lfg_get(prng) % (16*vals) - (8*vals);
143  block[63] = (block[0] & 1) ^ 1;
144  break;
145  }
146 }
147 
148 static void permute(int16_t dst[64], const int16_t src[64],
150 {
151  int i;
152 
153 #if ARCH_X86
154  if (permute_x86(dst, src, perm_type))
155  return;
156 #endif
157 
158  switch (perm_type) {
160  for (i = 0; i < 64; i++)
161  dst[(i & 0x38) | ((i & 6) >> 1) | ((i & 1) << 2)] = src[i];
162  break;
164  for (i = 0; i < 64; i++)
165  dst[(i & 0x24) | ((i & 3) << 3) | ((i >> 3) & 3)] = src[i];
166  break;
168  for (i = 0; i < 64; i++)
169  dst[(i>>3) | ((i<<3)&0x38)] = src[i];
170  break;
171  default:
172  for (i = 0; i < 64; i++)
173  dst[i] = src[i];
174  break;
175  }
176 }
177 
178 static int dct_error(const struct algo *dct, int test, int is_idct, int speed, const int bits)
179 {
180  void (*ref)(int16_t *block) = is_idct ? ff_ref_idct : ff_ref_fdct;
181  int it, i, scale;
182  int err_inf, v;
183  int64_t err2, ti, ti1, it1, err_sum = 0;
184  int64_t sysErr[64], sysErrMax = 0;
185  int64_t err2_matrix[64], err2_max = 0;
186  int maxout = 0;
187  int blockSumErrMax = 0, blockSumErr;
188  AVLFG prng;
189  const int vals=1<<bits;
190  double omse, ome;
191  int spec_err;
192 
193  av_lfg_init(&prng, 1);
194 
195  err_inf = 0;
196  err2 = 0;
197  for (i = 0; i < 64; i++)
198  err2_matrix[i] = sysErr[i] = 0;
199  for (it = 0; it < NB_ITS; it++) {
200  init_block(block1, test, is_idct, &prng, vals);
201  permute(block, block1, dct->perm_type);
202 
203  dct->func(block);
204  emms_c();
205 
206  if (!strcmp(dct->name, "IJG-AAN-INT")) {
207  for (i = 0; i < 64; i++) {
208  scale = 8 * (1 << (AANSCALE_BITS + 11)) / ff_aanscales[i];
209  block[i] = (block[i] * scale) >> AANSCALE_BITS;
210  }
211  }
212 
213  ref(block1);
214  if (!strcmp(dct->name, "PR-SSE2"))
215  for (i = 0; i < 64; i++)
216  block1[i] = av_clip(block1[i], 4-512, 1019-512);
217 
218  blockSumErr = 0;
219  for (i = 0; i < 64; i++) {
220  int err = block[i] - block1[i];
221  err_sum += err;
222  v = abs(err);
223  if (v > err_inf)
224  err_inf = v;
225  err2_matrix[i] += v * v;
226  err2 += v * v;
227  sysErr[i] += block[i] - block1[i];
228  blockSumErr += v;
229  if (abs(block[i]) > maxout)
230  maxout = abs(block[i]);
231  }
232  if (blockSumErrMax < blockSumErr)
233  blockSumErrMax = blockSumErr;
234  }
235  for (i = 0; i < 64; i++) {
236  sysErrMax = FFMAX(sysErrMax, FFABS(sysErr[i]));
237  err2_max = FFMAX(err2_max , FFABS(err2_matrix[i]));
238  }
239 
240  for (i = 0; i < 64; i++) {
241  if (i % 8 == 0)
242  printf("\n");
243  printf("%7d ", (int) sysErr[i]);
244  }
245  printf("\n");
246 
247  omse = (double) err2 / NB_ITS / 64;
248  ome = (double) err_sum / NB_ITS / 64;
249 
250  spec_err = is_idct && (err_inf > 1 || omse > 0.02 || fabs(ome) > 0.0015);
251  if (test < 2)
252  spec_err = is_idct && ((double) err2_max / NB_ITS > 0.06 || (double) sysErrMax / NB_ITS > 0.015);
253 
254  printf("%s %s: max_err=%d omse=%0.8f ome=%0.8f syserr=%0.8f maxout=%d blockSumErr=%d\n",
255  is_idct ? "IDCT" : "DCT", dct->name, err_inf,
256  omse, ome, (double) sysErrMax / NB_ITS,
257  maxout, blockSumErrMax);
258 
259  if (spec_err && !dct->nonspec) {
260  printf("Failed!\n");
261  return 1;
262  }
263 
264  if (!speed)
265  return 0;
266 
267  /* speed test */
268 
269  init_block(block, test, is_idct, &prng, vals);
270  permute(block1, block, dct->perm_type);
271 
272  ti = av_gettime_relative();
273  it1 = 0;
274  do {
275  for (it = 0; it < NB_ITS_SPEED; it++) {
276  memcpy(block, block1, sizeof(block));
277  dct->func(block);
278  }
279  emms_c();
280  it1 += NB_ITS_SPEED;
281  ti1 = av_gettime_relative() - ti;
282  } while (ti1 < 1000000);
283 
284  printf("%s %s: %0.1f kdct/s\n", is_idct ? "IDCT" : "DCT", dct->name,
285  (double) it1 * 1000.0 / (double) ti1);
286 
287  return 0;
288 }
289 
292 
293 static void idct248_ref(uint8_t *dest, ptrdiff_t linesize, int16_t *block)
294 {
295  static int init;
296  static double c8[8][8];
297  static double c4[4][4];
298  double block1[64], block2[64], block3[64];
299  double s, sum, v;
300  int i, j, k;
301 
302  if (!init) {
303  init = 1;
304 
305  for (i = 0; i < 8; i++) {
306  sum = 0;
307  for (j = 0; j < 8; j++) {
308  s = (i == 0) ? sqrt(1.0 / 8.0) : sqrt(1.0 / 4.0);
309  c8[i][j] = s * cos(M_PI * i * (j + 0.5) / 8.0);
310  sum += c8[i][j] * c8[i][j];
311  }
312  }
313 
314  for (i = 0; i < 4; i++) {
315  sum = 0;
316  for (j = 0; j < 4; j++) {
317  s = (i == 0) ? sqrt(1.0 / 4.0) : sqrt(1.0 / 2.0);
318  c4[i][j] = s * cos(M_PI * i * (j + 0.5) / 4.0);
319  sum += c4[i][j] * c4[i][j];
320  }
321  }
322  }
323 
324  /* butterfly */
325  s = 0.5 * sqrt(2.0);
326  for (i = 0; i < 4; i++) {
327  for (j = 0; j < 8; j++) {
328  block1[8 * (2 * i) + j] =
329  (block[8 * (2 * i) + j] + block[8 * (2 * i + 1) + j]) * s;
330  block1[8 * (2 * i + 1) + j] =
331  (block[8 * (2 * i) + j] - block[8 * (2 * i + 1) + j]) * s;
332  }
333  }
334 
335  /* idct8 on lines */
336  for (i = 0; i < 8; i++) {
337  for (j = 0; j < 8; j++) {
338  sum = 0;
339  for (k = 0; k < 8; k++)
340  sum += c8[k][j] * block1[8 * i + k];
341  block2[8 * i + j] = sum;
342  }
343  }
344 
345  /* idct4 */
346  for (i = 0; i < 8; i++) {
347  for (j = 0; j < 4; j++) {
348  /* top */
349  sum = 0;
350  for (k = 0; k < 4; k++)
351  sum += c4[k][j] * block2[8 * (2 * k) + i];
352  block3[8 * (2 * j) + i] = sum;
353 
354  /* bottom */
355  sum = 0;
356  for (k = 0; k < 4; k++)
357  sum += c4[k][j] * block2[8 * (2 * k + 1) + i];
358  block3[8 * (2 * j + 1) + i] = sum;
359  }
360  }
361 
362  /* clamp and store the result */
363  for (i = 0; i < 8; i++) {
364  for (j = 0; j < 8; j++) {
365  v = block3[8 * i + j];
366  if (v < 0) v = 0;
367  else if (v > 255) v = 255;
368  dest[i * linesize + j] = (int) rint(v);
369  }
370  }
371 }
372 
373 static void idct248_error(const char *name,
374  void (*idct248_put)(uint8_t *dest,
375  ptrdiff_t line_size,
376  int16_t *block),
377  int speed)
378 {
379  int it, i, it1, ti, ti1, err_max, v;
380  AVLFG prng;
381 
382  av_lfg_init(&prng, 1);
383 
384  /* just one test to see if code is correct (precision is less
385  important here) */
386  err_max = 0;
387  for (it = 0; it < NB_ITS; it++) {
388  /* XXX: use forward transform to generate values */
389  for (i = 0; i < 64; i++)
390  block1[i] = av_lfg_get(&prng) % 256 - 128;
391  block1[0] += 1024;
392 
393  for (i = 0; i < 64; i++)
394  block[i] = block1[i];
395  idct248_ref(img_dest1, 8, block);
396 
397  for (i = 0; i < 64; i++)
398  block[i] = block1[i];
399  idct248_put(img_dest, 8, block);
400 
401  for (i = 0; i < 64; i++) {
402  v = abs((int) img_dest[i] - (int) img_dest1[i]);
403  if (v == 255)
404  printf("%d %d\n", img_dest[i], img_dest1[i]);
405  if (v > err_max)
406  err_max = v;
407  }
408 #if 0
409  printf("ref=\n");
410  for(i=0;i<8;i++) {
411  int j;
412  for(j=0;j<8;j++) {
413  printf(" %3d", img_dest1[i*8+j]);
414  }
415  printf("\n");
416  }
417 
418  printf("out=\n");
419  for(i=0;i<8;i++) {
420  int j;
421  for(j=0;j<8;j++) {
422  printf(" %3d", img_dest[i*8+j]);
423  }
424  printf("\n");
425  }
426 #endif
427  }
428  printf("%s %s: err_inf=%d\n", 1 ? "IDCT248" : "DCT248", name, err_max);
429 
430  if (!speed)
431  return;
432 
433  ti = av_gettime_relative();
434  it1 = 0;
435  do {
436  for (it = 0; it < NB_ITS_SPEED; it++) {
437  for (i = 0; i < 64; i++)
438  block[i] = block1[i];
439  idct248_put(img_dest, 8, block);
440  }
441  emms_c();
442  it1 += NB_ITS_SPEED;
443  ti1 = av_gettime_relative() - ti;
444  } while (ti1 < 1000000);
445 
446  printf("%s %s: %0.1f kdct/s\n", 1 ? "IDCT248" : "DCT248", name,
447  (double) it1 * 1000.0 / (double) ti1);
448 }
449 
450 static void help(void)
451 {
452  printf("dct-test [-i] [<test-number>] [<bits>]\n"
453  "test-number 0 -> test with random matrixes\n"
454  " 1 -> test with random sparse matrixes\n"
455  " 2 -> do 3. test from MPEG-4 std\n"
456  "bits Number of time domain bits to use, 8 is default\n"
457  "-i test IDCT implementations\n"
458  "-4 test IDCT248 implementations\n"
459  "-t speed test\n");
460 }
461 
462 #if !HAVE_GETOPT
463 #include "compat/getopt.c"
464 #endif
465 
466 int main(int argc, char **argv)
467 {
468  int test_idct = 0, test_248_dct = 0;
469  int c, i;
470  int test = 1;
471  int speed = 0;
472  int err = 0;
473  int bits=8;
474 
475  ff_ref_dct_init();
476 
477  for (;;) {
478  c = getopt(argc, argv, "ih4t");
479  if (c == -1)
480  break;
481  switch (c) {
482  case 'i':
483  test_idct = 1;
484  break;
485  case '4':
486  test_248_dct = 1;
487  break;
488  case 't':
489  speed = 1;
490  break;
491  default:
492  case 'h':
493  help();
494  return 0;
495  }
496  }
497 
498  if (optind < argc)
499  test = atoi(argv[optind]);
500  if(optind+1 < argc) bits= atoi(argv[optind+1]);
501 
502  printf("ffmpeg DCT/IDCT test\n");
503 
504  if (test_248_dct) {
505  idct248_error("SIMPLE-C", ff_simple_idct248_put, speed);
506  } else {
507  const int cpu_flags = av_get_cpu_flags();
508  if (test_idct) {
509  for (i = 0; i < FF_ARRAY_ELEMS(idct_tab); i++)
510  err |= dct_error(&idct_tab[i], test, test_idct, speed, bits);
511 
512  for (i = 0; idct_tab_arch[i].name; i++)
513  if (!(~cpu_flags & idct_tab_arch[i].cpu_flag))
514  err |= dct_error(&idct_tab_arch[i], test, test_idct, speed, bits);
515  }
516 #if CONFIG_FDCTDSP
517  else {
518  for (i = 0; i < FF_ARRAY_ELEMS(fdct_tab); i++)
519  err |= dct_error(&fdct_tab[i], test, test_idct, speed, bits);
520 
521  for (i = 0; fdct_tab_arch[i].name; i++)
522  if (!(~cpu_flags & fdct_tab_arch[i].cpu_flag))
523  err |= dct_error(&fdct_tab_arch[i], test, test_idct, speed, bits);
524  }
525 #endif /* CONFIG_FDCTDSP */
526  }
527 
528  if (err)
529  printf("Error: %d.\n", err);
530 
531  return !!err;
532 }
static const struct algo idct_tab_arch[]
Definition: dct.c:107
Definition: lfg.h:27
idct_permutation_type
Definition: idctdsp.h:37
const char * s
Definition: avisynth_c.h:768
#define AANSCALE_BITS
Definition: dct.c:110
void ff_fdct_ifast(int16_t *data)
Definition: jfdctfst.c:208
static int optind
Definition: getopt.c:37
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
const char * name
Definition: dct.c:53
void ff_simple_idct_int16_8bit(int16_t *block)
static void ff_prores_idct_wrap(int16_t *dst)
Definition: dct.c:69
static atomic_int cpu_flags
Definition: cpu.c:50
#define src
Definition: vp8dsp.c:254
av_cold void ff_ref_dct_init(void)
Initialize the double precision discrete cosine transform functions fdct & idct.
Definition: dctref.c:41
static int16_t block[64]
Definition: dct.c:115
int nonspec
Definition: dct.c:57
uint8_t
void ff_faanidct(int16_t block[64])
Definition: faanidct.c:127
static int permute_x86(int16_t dst[64], const int16_t src[64], enum idct_permutation_type perm_type)
Definition: dct.c:118
#define emms_c()
Definition: internal.h:55
int cpu_flag
Definition: dct.c:56
void ff_simple_idct_int16_12bit(int16_t *block)
#define DECLARE_ALIGNED(n, t, v)
Declare a variable that is aligned in memory.
Definition: mem.h:112
const uint16_t ff_aanscales[64]
Definition: aandcttab.c:26
void ff_prores_idct(int16_t *block, const int16_t *qmat)
Special version of ff_simple_idct_int16_10bit() which does dequantization and scales by a factor of 2...
Definition: simple_idct.c:239
static void idct248_error(const char *name, void(*idct248_put)(uint8_t *dest, ptrdiff_t line_size, int16_t *block), int speed)
Definition: dct.c:373
static void help(void)
Definition: dct.c:450
static uint8_t img_dest1[64]
Definition: dct.c:291
#define FFMAX(a, b)
Definition: common.h:94
void(* func)(int16_t *block)
Definition: dct.c:54
common internal API header
Definition: dct.c:52
int main(int argc, char **argv)
Definition: dct.c:466
static void permute(int16_t dst[64], const int16_t src[64], enum idct_permutation_type perm_type)
Definition: dct.c:148
static void init_block(int16_t block[64], int test, int is_idct, AVLFG *prng, int vals)
Definition: dct.c:118
static const struct algo idct_tab[]
Definition: dct.c:82
#define FFABS(a)
Absolute value, Note, INT_MIN / INT64_MIN result in undefined behavior as they are not representable ...
Definition: common.h:72
static int dct_error(const struct algo *dct, int test, int is_idct, int speed, const int bits)
Definition: dct.c:178
#define FF_ARRAY_ELEMS(a)
#define rint
Definition: tablegen.h:41
void ff_jpeg_fdct_islow_8(int16_t *data)
void ff_j_rev_dct(int16_t *data)
void ff_faandct(int16_t *data)
Definition: faandct.c:114
typedef void(RENAME(mix_any_func_type))
static void test(const char *pattern, const char *host)
Definition: noproxy.c:23
static int getopt(int argc, char *argv[], char *opts)
Definition: getopt.c:41
static unsigned int av_lfg_get(AVLFG *c)
Get the next random unsigned 32-bit number using an ALFG.
Definition: lfg.h:47
static const struct algo fdct_tab_arch[]
Definition: dct.c:106
void ff_ref_fdct(short *block)
Transform 8x8 block of data with a double precision forward DCT This is a reference implementation...
Definition: dctref.c:59
av_cold void av_lfg_init(AVLFG *c, unsigned int seed)
Definition: lfg.c:32
int av_get_cpu_flags(void)
Return the flags which specify extensions supported by the CPU.
Definition: cpu.c:93
void ff_xvid_idct(int16_t *const in)
Definition: xvididct.c:291
void ff_simple_idct_int16_10bit(int16_t *block)
int64_t av_gettime_relative(void)
Get the current time in microseconds since some unspecified starting point.
Definition: time.c:56
static uint8_t img_dest[64]
Definition: dct.c:290
AAN (Arai, Agui and Nakajima) (I)DCT tables.
static void idct248_ref(uint8_t *dest, ptrdiff_t linesize, int16_t *block)
Definition: dct.c:293
int
common internal and external API header
static int ref[MAX_W *MAX_W]
Definition: jpeg2000dwt.c:107
#define LOCAL_ALIGNED(a, t, v,...)
Definition: internal.h:114
void ff_simple_idct248_put(uint8_t *dest, ptrdiff_t line_size, int16_t *block)
Definition: simple_idct.c:106
static double c[64]
#define NB_ITS_SPEED
Definition: dct.c:113
enum idct_permutation_type perm_type
Definition: dct.c:55
void ff_ref_idct(short *block)
Transform 8x8 block of data with a double precision inverse DCT This is a reference implementation...
Definition: dctref.c:95
simple idct header.
static int16_t block1[64]
Definition: dct.c:116
#define M_PI
Definition: mathematics.h:52
Floating point AAN DCT
static const struct algo fdct_tab[]
Definition: dct.c:60
#define NB_ITS
Definition: dct.c:112