FFmpeg
yuvcmp.c
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1 /*
2  * originally by Andreas Ă–man (andoma)
3  * some changes by Alexander Strange
4  */
5 
6 #include <string.h>
7 #include <stdlib.h>
8 #include <inttypes.h>
9 #include <stdio.h>
10 #include <sys/stat.h>
11 #include <fcntl.h>
12 
13 #if HAVE_UNISTD_H
14 #include <unistd.h>
15 #endif
16 
17 int
18 main(int argc, char **argv)
19 {
20  int fd[2];
21  int print_pixels = 0;
22  int dump_blocks = 0;
23 
24  int width;
25  int height;
26  int to_skip = 0;
27 
28  if (argc < 6) {
29  fprintf(stderr, "%s [YUV file 1] [YUV file 2] width height pixelcmp|blockdump (# to skip)\n", argv[0]);
30  return 1;
31  }
32 
33  width = atoi(argv[3]);
34  height = atoi(argv[4]);
35  if (argc > 6)
36  to_skip = atoi(argv[6]);
37 
38  uint8_t *Y[2], *C[2][2];
39  int i, v, c, p;
40  int lsiz = width * height;
41  int csiz = width * height / 4;
42  int x, y;
43  int cwidth = width / 2;
44  int fr = to_skip;
45  int mb;
46  char *mberrors;
47  int mb_x, mb_y;
48  uint8_t *a;
49  uint8_t *b;
50  int die = 0;
51 
52  print_pixels = strstr(argv[5], "pixelcmp") ? 1 : 0;
53  dump_blocks = strstr(argv[5], "blockdump") ? 1 : 0;
54 
55  for(i = 0; i < 2; i++) {
56  Y[i] = malloc(lsiz);
57  C[0][i] = malloc(csiz);
58  C[1][i] = malloc(csiz);
59 
60  fd[i] = open(argv[1 + i], O_RDONLY);
61  if(fd[i] == -1) {
62  perror("open");
63  exit(1);
64  }
65  fcntl(fd[i], F_NOCACHE, 1);
66 
67  if (to_skip)
68  lseek(fd[i], to_skip * (lsiz + 2*csiz), SEEK_SET);
69  }
70 
71  mb_x = width / 16;
72  mb_y = height / 16;
73 
74  mberrors = malloc(mb_x * mb_y);
75 
76  while(!die) {
77  memset(mberrors, 0, mb_x * mb_y);
78 
79  printf("Loading frame %d\n", ++fr);
80 
81  for(i = 0; i < 2; i++) {
82  v = read(fd[i], Y[i], lsiz);
83  if(v != lsiz) {
84  fprintf(stderr, "Unable to read Y from file %d, exiting\n", i + 1);
85  return 1;
86  }
87  }
88 
89 
90  for(c = 0; c < lsiz; c++) {
91  if(Y[0][c] != Y[1][c]) {
92  x = c % width;
93  y = c / width;
94 
95  mb = x / 16 + (y / 16) * mb_x;
96 
97  if(print_pixels)
98  printf("Luma diff 0x%02x != 0x%02x at pixel (%4d,%-4d) mb(%d,%d) #%d\n",
99  Y[0][c],
100  Y[1][c],
101  x, y,
102  x / 16,
103  y / 16,
104  mb);
105 
106  mberrors[mb] |= 1;
107  }
108  }
109 
110  /* Chroma planes */
111 
112  for(p = 0; p < 2; p++) {
113 
114  for(i = 0; i < 2; i++) {
115  v = read(fd[i], C[p][i], csiz);
116  if(v != csiz) {
117  fprintf(stderr, "Unable to read %c from file %d, exiting\n",
118  "UV"[p], i + 1);
119  return 1;
120  }
121  }
122 
123  for(c = 0; c < csiz; c++) {
124  if(C[p][0][c] != C[p][1][c]) {
125  x = c % cwidth;
126  y = c / cwidth;
127 
128  mb = x / 8 + (y / 8) * mb_x;
129 
130  mberrors[mb] |= 2 << p;
131 
132  if(print_pixels)
133 
134  printf("c%c diff 0x%02x != 0x%02x at pixel (%4d,%-4d) "
135  "mb(%3d,%-3d) #%d\n",
136  p ? 'r' : 'b',
137  C[p][0][c],
138  C[p][1][c],
139 
140  x, y,
141  x / 8,
142  y / 8,
143  x / 8 + y / 8 * cwidth / 8);
144  }
145  }
146  }
147 
148  for(i = 0; i < mb_x * mb_y; i++) {
149  x = i % mb_x;
150  y = i / mb_x;
151 
152  if(mberrors[i]) {
153  die = 1;
154 
155  printf("MB (%3d,%-3d) %4d %d %c%c%c damaged\n",
156  x, y, i, mberrors[i],
157  mberrors[i] & 1 ? 'Y' : ' ',
158  mberrors[i] & 2 ? 'U' : ' ',
159  mberrors[i] & 4 ? 'V' : ' ');
160 
161  if(dump_blocks) {
162  a = Y[0] + x * 16 + y * 16 * width;
163  b = Y[1] + x * 16 + y * 16 * width;
164 
165  for(y = 0; y < 16; y++) {
166  printf("%c ", "TB"[y&1]);
167  for(x = 0; x < 16; x++)
168  printf("%02x%c", a[x + y * width],
169  a[x + y * width] != b[x + y * width] ? '<' : ' ');
170 
171  printf("| ");
172  for(x = 0; x < 16; x++)
173  printf("%02x%c", b[x + y * width],
174  a[x + y * width] != b[x + y * width] ? '<' : ' ');
175 
176  printf("\n");
177  }
178  }
179  }
180  }
181  }
182 
183  return 0;
184 }
b
#define b
Definition: input.c:41
C
s EdgeDetect Foobar g libavfilter vf_edgedetect c libavfilter vf_foobar c edit libavfilter and add an entry for foobar following the pattern of the other filters edit libavfilter allfilters and add an entry for foobar following the pattern of the other filters configure make j< whatever > ffmpeg ffmpeg i you should get a foobar png with Lena edge detected That s your new playground is ready Some little details about what s going which in turn will define variables for the build system and the C
Definition: writing_filters.txt:58
width
#define width
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
printf
printf("static const uint8_t my_array[100] = {\n")
main
int main(int argc, char **argv)
Definition: yuvcmp.c:18
height
#define height
a
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:41
mb
#define mb
Definition: vf_colormatrix.c:99
Y
#define Y
Definition: boxblur.h:37
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
read
static uint32_t BS_FUNC() read(BSCTX *bc, unsigned int n)
Return n bits from the buffer, n has to be in the 0-32 range.
Definition: bitstream_template.h:231