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00023 #include <stdlib.h>
00024 #include <stdio.h>
00025 #include <inttypes.h>
00026
00027 #define FIXP (1<<16)
00028 #define MY_PI 205887 //(M_PI*FIX)
00029
00030 static int64_t int_pow(int64_t a, int p){
00031 int64_t v= FIXP;
00032
00033 for(; p; p--){
00034 v*= a;
00035 v/= FIXP;
00036 }
00037
00038 return v;
00039 }
00040
00041 static int64_t int_sin(int64_t a){
00042 if(a<0) a= MY_PI-a;
00043 a %= 2*MY_PI;
00044
00045 if(a>=MY_PI*3/2) a -= 2*MY_PI;
00046 if(a>=MY_PI/2 ) a = MY_PI - a;
00047
00048 return a - int_pow(a, 3)/6 + int_pow(a, 5)/120 - int_pow(a, 7)/5040;
00049 }
00050
00051 #define SCALEBITS 8
00052 #define ONE_HALF (1 << (SCALEBITS - 1))
00053 #define FIX(x) ((int) ((x) * (1L<<SCALEBITS) + 0.5))
00054 typedef unsigned char UINT8;
00055
00056 static void rgb24_to_yuv420p(UINT8 *lum, UINT8 *cb, UINT8 *cr,
00057 UINT8 *src, int width, int height)
00058 {
00059 int wrap, wrap3, x, y;
00060 int r, g, b, r1, g1, b1;
00061 UINT8 *p;
00062
00063 wrap = width;
00064 wrap3 = width * 3;
00065 p = src;
00066 for(y=0;y<height;y+=2) {
00067 for(x=0;x<width;x+=2) {
00068 r = p[0];
00069 g = p[1];
00070 b = p[2];
00071 r1 = r;
00072 g1 = g;
00073 b1 = b;
00074 lum[0] = (FIX(0.29900) * r + FIX(0.58700) * g +
00075 FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
00076 r = p[3];
00077 g = p[4];
00078 b = p[5];
00079 r1 += r;
00080 g1 += g;
00081 b1 += b;
00082 lum[1] = (FIX(0.29900) * r + FIX(0.58700) * g +
00083 FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
00084 p += wrap3;
00085 lum += wrap;
00086
00087 r = p[0];
00088 g = p[1];
00089 b = p[2];
00090 r1 += r;
00091 g1 += g;
00092 b1 += b;
00093 lum[0] = (FIX(0.29900) * r + FIX(0.58700) * g +
00094 FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
00095 r = p[3];
00096 g = p[4];
00097 b = p[5];
00098 r1 += r;
00099 g1 += g;
00100 b1 += b;
00101 lum[1] = (FIX(0.29900) * r + FIX(0.58700) * g +
00102 FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
00103
00104 cb[0] = ((- FIX(0.16874) * r1 - FIX(0.33126) * g1 +
00105 FIX(0.50000) * b1 + 4 * ONE_HALF - 1) >> (SCALEBITS + 2)) + 128;
00106 cr[0] = ((FIX(0.50000) * r1 - FIX(0.41869) * g1 -
00107 FIX(0.08131) * b1 + 4 * ONE_HALF - 1) >> (SCALEBITS + 2)) + 128;
00108
00109 cb++;
00110 cr++;
00111 p += -wrap3 + 2 * 3;
00112 lum += -wrap + 2;
00113 }
00114 p += wrap3;
00115 lum += wrap;
00116 }
00117 }
00118
00119
00120 #define DEFAULT_WIDTH 352
00121 #define DEFAULT_HEIGHT 288
00122 #define DEFAULT_NB_PICT 50
00123
00124 static void pgmyuv_save(const char *filename, int w, int h,
00125 unsigned char *rgb_tab)
00126 {
00127 FILE *f;
00128 int i, h2, w2;
00129 unsigned char *cb, *cr;
00130 unsigned char *lum_tab, *cb_tab, *cr_tab;
00131
00132 lum_tab = malloc(w * h);
00133 cb_tab = malloc((w * h) / 4);
00134 cr_tab = malloc((w * h) / 4);
00135
00136 rgb24_to_yuv420p(lum_tab, cb_tab, cr_tab, rgb_tab, w, h);
00137
00138 f = fopen(filename,"wb");
00139 fprintf(f, "P5\n%d %d\n%d\n", w, (h * 3) / 2, 255);
00140 fwrite(lum_tab, 1, w * h, f);
00141 h2 = h / 2;
00142 w2 = w / 2;
00143 cb = cb_tab;
00144 cr = cr_tab;
00145 for(i=0;i<h2;i++) {
00146 fwrite(cb, 1, w2, f);
00147 fwrite(cr, 1, w2, f);
00148 cb += w2;
00149 cr += w2;
00150 }
00151 fclose(f);
00152
00153 free(lum_tab);
00154 free(cb_tab);
00155 free(cr_tab);
00156 }
00157
00158 unsigned char *rgb_tab;
00159 int width, height, wrap;
00160
00161 static void put_pixel(int x, int y, int r, int g, int b)
00162 {
00163 unsigned char *p;
00164
00165 if (x < 0 || x >= width ||
00166 y < 0 || y >= height)
00167 return;
00168
00169 p = rgb_tab + y * wrap + x * 3;
00170 p[0] = r;
00171 p[1] = g;
00172 p[2] = b;
00173 }
00174
00175 unsigned char tab_r[256*256];
00176 unsigned char tab_g[256*256];
00177 unsigned char tab_b[256*256];
00178
00179 int teta = 0;
00180 int h_cos [360];
00181 int h_sin [360];
00182
00183 static int ipol(uint8_t *src, int x, int y){
00184 int int_x= x>>16;
00185 int int_y= y>>16;
00186 int frac_x= x&0xFFFF;
00187 int frac_y= y&0xFFFF;
00188 int s00= src[ ( int_x &255) + 256*( int_y &255) ];
00189 int s01= src[ ((int_x+1)&255) + 256*( int_y &255) ];
00190 int s10= src[ ( int_x &255) + 256*((int_y+1)&255) ];
00191 int s11= src[ ((int_x+1)&255) + 256*((int_y+1)&255) ];
00192 int s0= (((1<<16) - frac_x)*s00 + frac_x*s01)>>8;
00193 int s1= (((1<<16) - frac_x)*s10 + frac_x*s11)>>8;
00194
00195 return (((1<<16) - frac_y)*s0 + frac_y*s1)>>24;
00196 }
00197
00198 static void gen_image(int num, int w, int h)
00199 {
00200 const int c = h_cos [teta];
00201 const int s = h_sin [teta];
00202
00203 const int xi = -(w/2) * c;
00204 const int yi = (w/2) * s;
00205
00206 const int xj = -(h/2) * s;
00207 const int yj = -(h/2) * c;
00208 int i,j;
00209
00210 int x,y;
00211 int xprime = xj;
00212 int yprime = yj;
00213
00214
00215 for (j=0;j<h;j++) {
00216
00217 x = xprime + xi + FIXP*w/2;
00218 xprime += s;
00219
00220 y = yprime + yi + FIXP*h/2;
00221 yprime += c;
00222
00223 for ( i=0 ; i<w ; i++ ) {
00224 x += c;
00225 y -= s;
00226 #if 1
00227 put_pixel(i, j, ipol(tab_r, x, y), ipol(tab_g, x, y), ipol(tab_b, x, y));
00228 #else
00229 {
00230 unsigned dep;
00231 dep = ((x>>16)&255) + (((y>>16)&255)<<8);
00232 put_pixel(i, j, tab_r[dep], tab_g[dep], tab_b[dep]);
00233 }
00234 #endif
00235 }
00236 }
00237 teta = (teta+1) % 360;
00238 }
00239
00240 #define W 256
00241 #define H 256
00242
00243 static void init_demo(const char *filename) {
00244 int i,j;
00245 int h;
00246 int radian;
00247 char line[3 * W];
00248
00249 FILE *fichier;
00250
00251 fichier = fopen(filename,"rb");
00252 if (!fichier) {
00253 perror(filename);
00254 exit(1);
00255 }
00256
00257 fread(line, 1, 15, fichier);
00258 for (i=0;i<H;i++) {
00259 fread(line,1,3*W,fichier);
00260 for (j=0;j<W;j++) {
00261 tab_r[W*i+j] = line[3*j ];
00262 tab_g[W*i+j] = line[3*j + 1];
00263 tab_b[W*i+j] = line[3*j + 2];
00264 }
00265 }
00266 fclose(fichier);
00267
00268
00269 for (i=0;i<360;i++) {
00270 radian = 2*i*MY_PI/360;
00271 h = 2*FIXP + int_sin (radian);
00272 h_cos[i] = ( h * int_sin (radian + MY_PI/2) )/2/FIXP;
00273 h_sin[i] = ( h * int_sin (radian ) )/2/FIXP;
00274 }
00275 }
00276
00277 int main(int argc, char **argv)
00278 {
00279 int w, h, i;
00280 char buf[1024];
00281
00282 if (argc != 3) {
00283 printf("usage: %s directory/ image.pnm\n"
00284 "generate a test video stream\n", argv[0]);
00285 exit(1);
00286 }
00287
00288 w = DEFAULT_WIDTH;
00289 h = DEFAULT_HEIGHT;
00290
00291 rgb_tab = malloc(w * h * 3);
00292 wrap = w * 3;
00293 width = w;
00294 height = h;
00295
00296 init_demo(argv[2]);
00297
00298 for(i=0;i<DEFAULT_NB_PICT;i++) {
00299 snprintf(buf, sizeof(buf), "%s%02d.pgm", argv[1], i);
00300 gen_image(i, w, h);
00301 pgmyuv_save(buf, w, h, rgb_tab);
00302 }
00303
00304 free(rgb_tab);
00305 return 0;
00306 }