rotozoom.c
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1 /*
2  * Generate a synthetic YUV video sequence suitable for codec testing.
3  *
4  * copyright (c) Sebastien Bechet <s.bechet@av7.net>
5  *
6  * This file is part of Libav.
7  *
8  * Libav is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * Libav is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include <stdlib.h>
24 #include <stdio.h>
25 #include <inttypes.h>
26 
27 #define FIXP (1 << 16)
28 #define MY_PI 205887 // (M_PI * FIX)
29 
30 static int64_t int_pow(int64_t a, int p)
31 {
32  int64_t v = FIXP;
33 
34  for (; p; p--) {
35  v *= a;
36  v /= FIXP;
37  }
38 
39  return v;
40 }
41 
42 static int64_t int_sin(int64_t a)
43 {
44  if (a < 0)
45  a = MY_PI - a; // 0..inf
46  a %= 2 * MY_PI; // 0..2PI
47 
48  if (a >= MY_PI * 3 / 2)
49  a -= 2 * MY_PI; // -PI / 2 .. 3PI / 2
50  if (a >= MY_PI / 2)
51  a = MY_PI - a; // -PI / 2 .. PI / 2
52 
53  return a - int_pow(a, 3) / 6 + int_pow(a, 5) / 120 - int_pow(a, 7) / 5040;
54 }
55 
56 #define SCALEBITS 8
57 #define ONE_HALF (1 << (SCALEBITS - 1))
58 #define FIX(x) ((int) ((x) * (1L << SCALEBITS) + 0.5))
59 
60 static void rgb24_to_yuv420p(unsigned char *lum, unsigned char *cb,
61  unsigned char *cr, unsigned char *src,
62  int width, int height)
63 {
64  int wrap, wrap3, x, y;
65  int r, g, b, r1, g1, b1;
66  unsigned char *p;
67 
68  wrap = width;
69  wrap3 = width * 3;
70  p = src;
71  for (y = 0; y < height; y += 2) {
72  for (x = 0; x < width; x += 2) {
73  r = p[0];
74  g = p[1];
75  b = p[2];
76  r1 = r;
77  g1 = g;
78  b1 = b;
79  lum[0] = (FIX(0.29900) * r + FIX(0.58700) * g +
80  FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
81  r = p[3];
82  g = p[4];
83  b = p[5];
84  r1 += r;
85  g1 += g;
86  b1 += b;
87  lum[1] = (FIX(0.29900) * r + FIX(0.58700) * g +
88  FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
89  p += wrap3;
90  lum += wrap;
91 
92  r = p[0];
93  g = p[1];
94  b = p[2];
95  r1 += r;
96  g1 += g;
97  b1 += b;
98  lum[0] = (FIX(0.29900) * r + FIX(0.58700) * g +
99  FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
100  r = p[3];
101  g = p[4];
102  b = p[5];
103  r1 += r;
104  g1 += g;
105  b1 += b;
106  lum[1] = (FIX(0.29900) * r + FIX(0.58700) * g +
107  FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
108 
109  cb[0] = ((- FIX(0.16874) * r1 - FIX(0.33126) * g1 +
110  FIX(0.50000) * b1 + 4 * ONE_HALF - 1) >> (SCALEBITS + 2)) + 128;
111  cr[0] = ((FIX(0.50000) * r1 - FIX(0.41869) * g1 -
112  FIX(0.08131) * b1 + 4 * ONE_HALF - 1) >> (SCALEBITS + 2)) + 128;
113 
114  cb++;
115  cr++;
116  p += -wrap3 + 2 * 3;
117  lum += -wrap + 2;
118  }
119  p += wrap3;
120  lum += wrap;
121  }
122 }
123 
124 /* cif format */
125 #define DEFAULT_WIDTH 352
126 #define DEFAULT_HEIGHT 288
127 #define DEFAULT_NB_PICT 50
128 
129 static void pgmyuv_save(const char *filename, int w, int h,
130  unsigned char *rgb_tab)
131 {
132  FILE *f;
133  int i, h2, w2;
134  unsigned char *cb, *cr;
135  unsigned char *lum_tab, *cb_tab, *cr_tab;
136 
137  lum_tab = malloc(w * h);
138  cb_tab = malloc(w * h / 4);
139  cr_tab = malloc(w * h / 4);
140 
141  rgb24_to_yuv420p(lum_tab, cb_tab, cr_tab, rgb_tab, w, h);
142 
143  f = fopen(filename, "wb");
144  fprintf(f, "P5\n%d %d\n%d\n", w, h * 3 / 2, 255);
145  fwrite(lum_tab, 1, w * h, f);
146  h2 = h / 2;
147  w2 = w / 2;
148  cb = cb_tab;
149  cr = cr_tab;
150  for (i = 0; i < h2; i++) {
151  fwrite(cb, 1, w2, f);
152  fwrite(cr, 1, w2, f);
153  cb += w2;
154  cr += w2;
155  }
156  fclose(f);
157 
158  free(lum_tab);
159  free(cb_tab);
160  free(cr_tab);
161 }
162 
163 unsigned char *rgb_tab;
165 
166 static void put_pixel(int x, int y, int r, int g, int b)
167 {
168  unsigned char *p;
169 
170  if (x < 0 || x >= width ||
171  y < 0 || y >= height)
172  return;
173 
174  p = rgb_tab + y * wrap + x * 3;
175  p[0] = r;
176  p[1] = g;
177  p[2] = b;
178 }
179 
180 unsigned char tab_r[256 * 256];
181 unsigned char tab_g[256 * 256];
182 unsigned char tab_b[256 * 256];
183 
184 int h_cos[360];
185 int h_sin[360];
186 
187 static int ipol(uint8_t *src, int x, int y)
188 {
189  int int_x = x >> 16;
190  int int_y = y >> 16;
191  int frac_x = x & 0xFFFF;
192  int frac_y = y & 0xFFFF;
193  int s00 = src[( int_x & 255) + 256 * ( int_y & 255)];
194  int s01 = src[((int_x + 1) & 255) + 256 * ( int_y & 255)];
195  int s10 = src[( int_x & 255) + 256 * ((int_y + 1) & 255)];
196  int s11 = src[((int_x + 1) & 255) + 256 * ((int_y + 1) & 255)];
197  int s0 = (((1 << 16) - frac_x) * s00 + frac_x * s01) >> 8;
198  int s1 = (((1 << 16) - frac_x) * s10 + frac_x * s11) >> 8;
199 
200  return (((1 << 16) - frac_y) * s0 + frac_y * s1) >> 24;
201 }
202 
203 static void gen_image(int num, int w, int h)
204 {
205  const int c = h_cos[num % 360];
206  const int s = h_sin[num % 360];
207 
208  const int xi = -(w / 2) * c;
209  const int yi = (w / 2) * s;
210 
211  const int xj = -(h / 2) * s;
212  const int yj = -(h / 2) * c;
213  int i, j;
214 
215  int x, y;
216  int xprime = xj;
217  int yprime = yj;
218 
219  for (j = 0; j < h; j++) {
220  x = xprime + xi + FIXP * w / 2;
221  xprime += s;
222 
223  y = yprime + yi + FIXP * h / 2;
224  yprime += c;
225 
226  for (i = 0; i < w; i++) {
227  x += c;
228  y -= s;
229  put_pixel(i, j,
230  ipol(tab_r, x, y),
231  ipol(tab_g, x, y),
232  ipol(tab_b, x, y));
233  }
234  }
235 }
236 
237 #define W 256
238 #define H 256
239 
240 static int init_demo(const char *filename)
241 {
242  int i, j;
243  int h;
244  int radian;
245  char line[3 * W];
246 
247  FILE *input_file;
248 
249  input_file = fopen(filename, "rb");
250  if (!input_file) {
251  perror(filename);
252  return 1;
253  }
254 
255  if (fread(line, 1, 15, input_file) != 15)
256  return 1;
257  for (i = 0; i < H; i++) {
258  if (fread(line, 1, 3 * W, input_file) != 3 * W)
259  return 1;
260  for (j = 0; j < W; j++) {
261  tab_r[W * i + j] = line[3 * j ];
262  tab_g[W * i + j] = line[3 * j + 1];
263  tab_b[W * i + j] = line[3 * j + 2];
264  }
265  }
266  fclose(input_file);
267 
268  /* tables sin/cos */
269  for (i = 0; i < 360; i++) {
270  radian = 2 * i * MY_PI / 360;
271  h = 2 * FIXP + int_sin(radian);
272  h_cos[i] = h * int_sin(radian + MY_PI / 2) / 2 / FIXP;
273  h_sin[i] = h * int_sin(radian) / 2 / FIXP;
274  }
275 
276  return 0;
277 }
278 
279 int main(int argc, char **argv)
280 {
281  int w, h, i;
282  char buf[1024];
283 
284  if (argc != 3) {
285  printf("usage: %s directory/ image.pnm\n"
286  "generate a test video stream\n", argv[0]);
287  return 1;
288  }
289 
290  w = DEFAULT_WIDTH;
291  h = DEFAULT_HEIGHT;
292 
293  rgb_tab = malloc(w * h * 3);
294  wrap = w * 3;
295  width = w;
296  height = h;
297 
298  if (init_demo(argv[2]))
299  return 1;
300 
301  for (i = 0; i < DEFAULT_NB_PICT; i++) {
302  snprintf(buf, sizeof(buf), "%s%02d.pgm", argv[1], i);
303  gen_image(i, w, h);
304  pgmyuv_save(buf, w, h, rgb_tab);
305  }
306 
307  free(rgb_tab);
308  return 0;
309 }