FFmpeg
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 FFmpeg.
7  *
8  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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 #include "utils.c"
28 
29 #define FIXP (1 << 16)
30 #define MY_PI 205887 // (M_PI * FIX)
31 
32 static int64_t int_pow(int64_t a, int p)
33 {
34  int64_t v = FIXP;
35 
36  for (; p; p--) {
37  v *= a;
38  v /= FIXP;
39  }
40 
41  return v;
42 }
43 
44 static int64_t int_sin(int64_t a)
45 {
46  if (a < 0)
47  a = MY_PI - a; // 0..inf
48  a %= 2 * MY_PI; // 0..2PI
49 
50  if (a >= MY_PI * 3 / 2)
51  a -= 2 * MY_PI; // -PI / 2 .. 3PI / 2
52  if (a >= MY_PI / 2)
53  a = MY_PI - a; // -PI / 2 .. PI / 2
54 
55  return a - int_pow(a, 3) / 6 + int_pow(a, 5) / 120 - int_pow(a, 7) / 5040;
56 }
57 
58 static unsigned char tab_r[256 * 256];
59 static unsigned char tab_g[256 * 256];
60 static unsigned char tab_b[256 * 256];
61 
62 static int h_cos[360];
63 static int h_sin[360];
64 
65 static int ipol(uint8_t *src, int x, int y)
66 {
67  int int_x = x >> 16;
68  int int_y = y >> 16;
69  int frac_x = x & 0xFFFF;
70  int frac_y = y & 0xFFFF;
71  int s00 = src[( int_x & 255) + 256 * ( int_y & 255)];
72  int s01 = src[((int_x + 1) & 255) + 256 * ( int_y & 255)];
73  int s10 = src[( int_x & 255) + 256 * ((int_y + 1) & 255)];
74  int s11 = src[((int_x + 1) & 255) + 256 * ((int_y + 1) & 255)];
75  int s0 = (((1 << 16) - frac_x) * s00 + frac_x * s01) >> 8;
76  int s1 = (((1 << 16) - frac_x) * s10 + frac_x * s11) >> 8;
77 
78  return (((1 << 16) - frac_y) * s0 + frac_y * s1) >> 24;
79 }
80 
81 static void gen_image(int num, int w, int h)
82 {
83  const int c = h_cos[num % 360];
84  const int s = h_sin[num % 360];
85 
86  const int xi = -(w / 2) * c;
87  const int yi = (w / 2) * s;
88 
89  const int xj = -(h / 2) * s;
90  const int yj = -(h / 2) * c;
91  int i, j;
92 
93  int x, y;
94  int xprime = xj;
95  int yprime = yj;
96 
97  for (j = 0; j < h; j++) {
98  x = xprime + xi + FIXP * w / 2;
99  xprime += s;
100 
101  y = yprime + yi + FIXP * h / 2;
102  yprime += c;
103 
104  for (i = 0; i < w; i++) {
105  x += c;
106  y -= s;
107  put_pixel(i, j,
108  ipol(tab_r, x, y),
109  ipol(tab_g, x, y),
110  ipol(tab_b, x, y));
111  }
112  }
113 }
114 
115 #define W 256
116 #define H 256
117 
118 static int init_demo(const char *filename)
119 {
120  int i, j;
121  int h;
122  int radian;
123  char line[3 * W];
124 
125  FILE *input_file;
126 
127  input_file = fopen(filename, "rb");
128  if (!input_file) {
129  perror(filename);
130  return 1;
131  }
132 
133  if (fread(line, 1, 15, input_file) != 15)
134  return 1;
135  for (i = 0; i < H; i++) {
136  if (fread(line, 1, 3 * W, input_file) != 3 * W)
137  return 1;
138  for (j = 0; j < W; j++) {
139  tab_r[W * i + j] = line[3 * j ];
140  tab_g[W * i + j] = line[3 * j + 1];
141  tab_b[W * i + j] = line[3 * j + 2];
142  }
143  }
144  fclose(input_file);
145 
146  /* tables sin/cos */
147  for (i = 0; i < 360; i++) {
148  radian = 2 * i * MY_PI / 360;
149  h = 2 * FIXP + int_sin(radian);
150  h_cos[i] = h * int_sin(radian + MY_PI / 2) / 2 / FIXP;
151  h_sin[i] = h * int_sin(radian) / 2 / FIXP;
152  }
153 
154  return 0;
155 }
156 
157 int main(int argc, char **argv)
158 {
159  int w, h, i;
160  char buf[1024];
161  int isdir = 0;
162 
163  if (argc != 3) {
164  printf("usage: %s image.pnm file|dir\n"
165  "generate a test video stream\n", argv[0]);
166  return 1;
167  }
168 
169  if (!freopen(argv[2], "wb", stdout))
170  isdir = 1;
171 
172  w = DEFAULT_WIDTH;
173  h = DEFAULT_HEIGHT;
174 
175  rgb_tab = malloc(w * h * 3);
176  wrap = w * 3;
177  width = w;
178  height = h;
179 
180  if (init_demo(argv[1]))
181  return 1;
182 
183  for (i = 0; i < DEFAULT_NB_PICT; i++) {
184  gen_image(i, w, h);
185  if (isdir) {
186  snprintf(buf, sizeof(buf), "%s%02d.pgm", argv[2], i);
187  pgmyuv_save(buf, w, h, rgb_tab);
188  } else {
189  pgmyuv_save(NULL, w, h, rgb_tab);
190  }
191  }
192 
193  free(rgb_tab);
194  return 0;
195 }
#define NULL
Definition: coverity.c:32
static unsigned char tab_g[256 *256]
Definition: rotozoom.c:59
#define MY_PI
Definition: rotozoom.c:30
static void put_pixel(uint16_t *dst, ptrdiff_t linesize, const int16_t *in, int bits_per_raw_sample)
Add bias value, clamp and output pixels of a slice.
Definition: proresdsp.c:41
#define FIXP
Definition: rotozoom.c:29
static int64_t int_pow(int64_t a, int p)
Definition: rotozoom.c:32
static void pgmyuv_save(const char *filename, int w, int h, const unsigned char *rgb_tab)
Definition: utils.c:106
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:36
#define src
Definition: vp8dsp.c:254
static unsigned char tab_b[256 *256]
Definition: rotozoom.c:60
#define H
Definition: rotozoom.c:116
static int64_t int_sin(int64_t a)
Definition: rotozoom.c:44
static int h_sin[360]
Definition: rotozoom.c:63
static unsigned char * rgb_tab
Definition: utils.c:157
uint8_t
#define DEFAULT_NB_PICT
Definition: utils.c:104
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
#define height
#define DEFAULT_WIDTH
Definition: utils.c:102
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define s0
Definition: regdef.h:37
#define wrap(func)
Definition: neontest.h:65
Definition: graph2dot.c:48
static unsigned char tab_r[256 *256]
Definition: rotozoom.c:58
#define xi(width, name, var, range_min, range_max, subs,...)
Definition: cbs_h2645.c:386
#define width
uint8_t w
Definition: llviddspenc.c:38
#define s(width, name)
Definition: cbs_vp9.c:257
#define W
Definition: rotozoom.c:115
int main(int argc, char **argv)
Definition: rotozoom.c:157
void * buf
Definition: avisynth_c.h:766
#define DEFAULT_HEIGHT
Definition: utils.c:103
#define s1
Definition: regdef.h:38
#define snprintf
Definition: snprintf.h:34
static int h_cos[360]
Definition: rotozoom.c:62
static void gen_image(int num, int w, int h)
Definition: rotozoom.c:81
printf("static const uint8_t my_array[100] = {\n")
static int init_demo(const char *filename)
Definition: rotozoom.c:118
static int ipol(uint8_t *src, int x, int y)
Definition: rotozoom.c:65