FFmpeg
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videogen.c
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1 /*
2  * Generate a synthetic YUV video sequence suitable for codec testing.
3  * NOTE: No floats are used to guarantee bitexact output.
4  *
5  * Copyright (c) 2002 Fabrice Bellard
6  *
7  * This file is part of FFmpeg.
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 
24 #include <stdlib.h>
25 #include <stdint.h>
26 #include <stdio.h>
27 
28 #include "utils.c"
29 
30 static unsigned int myrnd(unsigned int *seed_ptr, int n)
31 {
32  unsigned int seed, val;
33 
34  seed = *seed_ptr;
35  seed = (seed * 314159) + 1;
36  if (n == 256) {
37  val = seed >> 24;
38  } else {
39  val = seed % n;
40  }
41  *seed_ptr = seed;
42  return val;
43 }
44 
45 #define NOISE_X 10
46 #define NOISE_Y 30
47 #define NOISE_W 26
48 
49 #define FRAC_BITS 8
50 #define FRAC_ONE (1 << FRAC_BITS)
51 
52 /* cosine approximate with 1-x^2 */
53 static int int_cos(int a)
54 {
55  int v, neg;
56  a = a & (FRAC_ONE - 1);
57  if (a >= (FRAC_ONE / 2))
58  a = FRAC_ONE - a;
59  neg = 0;
60  if (a > (FRAC_ONE / 4)) {
61  neg = -1;
62  a = (FRAC_ONE / 2) - a;
63  }
64  v = FRAC_ONE - ((a * a) >> 4);
65  v = (v ^ neg) - neg;
66  return v;
67 }
68 
69 #define NB_OBJS 10
70 
71 typedef struct VObj {
72  int x, y, w, h;
73  int r, g, b;
74 } VObj;
75 
76 static VObj objs[NB_OBJS];
77 
78 static unsigned int seed = 1;
79 
80 static void gen_image(int num, int w, int h)
81 {
82  int r, g, b, x, y, i, dx, dy, x1, y1;
83  unsigned int seed1;
84 
85  if (num == 0) {
86  for (i = 0; i < NB_OBJS; i++) {
87  objs[i].x = myrnd(&seed, w);
88  objs[i].y = myrnd(&seed, h);
89  objs[i].w = myrnd(&seed, w / 4) + 10;
90  objs[i].h = myrnd(&seed, h / 4) + 10;
91  objs[i].r = myrnd(&seed, 256);
92  objs[i].g = myrnd(&seed, 256);
93  objs[i].b = myrnd(&seed, 256);
94  }
95  }
96 
97  /* first a moving background with gradients */
98  /* test motion estimation */
99  dx = int_cos(num * FRAC_ONE / 50) * 35;
100  dy = int_cos(num * FRAC_ONE / 50 + FRAC_ONE / 10) * 30;
101  for (y = 0; y < h; y++) {
102  for (x = 0; x < w; x++) {
103  x1 = (x << FRAC_BITS) + dx;
104  y1 = (y << FRAC_BITS) + dy;
105  r = ((y1 * 7) >> FRAC_BITS) & 0xff;
106  g = (((x1 + y1) * 9) >> FRAC_BITS) & 0xff;
107  b = ((x1 * 5) >> FRAC_BITS) & 0xff;
108  put_pixel(x, y, r, g, b);
109  }
110  }
111 
112  /* then some noise with very high intensity to test saturation */
113  seed1 = num;
114  for (y = 0; y < NOISE_W; y++) {
115  for (x = 0; x < NOISE_W; x++) {
116  r = myrnd(&seed1, 256);
117  g = myrnd(&seed1, 256);
118  b = myrnd(&seed1, 256);
119  put_pixel(x + NOISE_X, y + NOISE_Y, r, g, b);
120  }
121  }
122 
123  /* then moving objects */
124  for (i = 0; i < NB_OBJS; i++) {
125  VObj *p = &objs[i];
126  seed1 = i;
127  for (y = 0; y < p->h; y++) {
128  for (x = 0; x < p->w; x++) {
129  r = p->r;
130  g = p->g;
131  b = p->b;
132  /* add a per object noise */
133  r += myrnd(&seed1, 50);
134  g += myrnd(&seed1, 50);
135  b += myrnd(&seed1, 50);
136  put_pixel(x + p->x, y + p->y, r, g, b);
137  }
138  }
139  p->x += myrnd(&seed, 21) - 10;
140  p->y += myrnd(&seed, 21) - 10;
141  }
142 }
143 
144 int main(int argc, char **argv)
145 {
146  int w, h, i;
147  char buf[1024];
148  int isdir = 0;
149 
150  if (argc != 2) {
151  printf("usage: %s file|dir\n"
152  "generate a test video stream\n", argv[0]);
153  exit(1);
154  }
155 
156  if (!freopen(argv[1], "wb", stdout))
157  isdir = 1;
158 
159  w = DEFAULT_WIDTH;
160  h = DEFAULT_HEIGHT;
161 
162  rgb_tab = malloc(w * h * 3);
163  wrap = w * 3;
164  width = w;
165  height = h;
166 
167  for (i = 0; i < DEFAULT_NB_PICT; i++) {
168  gen_image(i, w, h);
169  if (isdir) {
170  snprintf(buf, sizeof(buf), "%s%02d.pgm", argv[1], i);
171  pgmyuv_save(buf, w, h, rgb_tab);
172  } else {
173  pgmyuv_save(NULL, w, h, rgb_tab);
174  }
175  }
176 
177  free(rgb_tab);
178  return 0;
179 }