/* * This file is part of Libav. * * Libav is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * Libav is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include <errno.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #define SCALEBITS 8 #define ONE_HALF (1 << (SCALEBITS - 1)) #define FIX(x) ((int) ((x) * (1L << SCALEBITS) + 0.5)) #define err_if(expr) do { \ if (expr) { \ fprintf(stderr, "%s\n", strerror(errno)); \ exit(1); \ } \ } while (0) static void rgb24_to_yuv420p(unsigned char *lum, unsigned char *cb, unsigned char *cr, unsigned char *src, int width, int height) { int wrap, wrap3, x, y; int r, g, b, r1, g1, b1; unsigned char *p; wrap = width; wrap3 = width * 3; p = src; for (y = 0; y < height; y += 2) { for (x = 0; x < width; x += 2) { r = p[0]; g = p[1]; b = p[2]; r1 = r; g1 = g; b1 = b; lum[0] = (FIX(0.29900) * r + FIX(0.58700) * g + FIX(0.11400) * b + ONE_HALF) >> SCALEBITS; r = p[3]; g = p[4]; b = p[5]; r1 += r; g1 += g; b1 += b; lum[1] = (FIX(0.29900) * r + FIX(0.58700) * g + FIX(0.11400) * b + ONE_HALF) >> SCALEBITS; p += wrap3; lum += wrap; r = p[0]; g = p[1]; b = p[2]; r1 += r; g1 += g; b1 += b; lum[0] = (FIX(0.29900) * r + FIX(0.58700) * g + FIX(0.11400) * b + ONE_HALF) >> SCALEBITS; r = p[3]; g = p[4]; b = p[5]; r1 += r; g1 += g; b1 += b; lum[1] = (FIX(0.29900) * r + FIX(0.58700) * g + FIX(0.11400) * b + ONE_HALF) >> SCALEBITS; cb[0] = ((- FIX(0.16874) * r1 - FIX(0.33126) * g1 + FIX(0.50000) * b1 + 4 * ONE_HALF - 1) >> (SCALEBITS + 2)) + 128; cr[0] = ((FIX(0.50000) * r1 - FIX(0.41869) * g1 - FIX(0.08131) * b1 + 4 * ONE_HALF - 1) >> (SCALEBITS + 2)) + 128; cb++; cr++; p += -wrap3 + 2 * 3; lum += -wrap + 2; } p += wrap3; lum += wrap; } } /* cif format */ #define DEFAULT_WIDTH 352 #define DEFAULT_HEIGHT 288 #define DEFAULT_NB_PICT 50 static void pgmyuv_save(const char *filename, int w, int h, unsigned char *rgb_tab) { FILE *f; int i, h2, w2; unsigned char *cb, *cr; unsigned char *lum_tab, *cb_tab, *cr_tab; lum_tab = malloc(w * h); cb_tab = malloc(w * h / 4); cr_tab = malloc(w * h / 4); rgb24_to_yuv420p(lum_tab, cb_tab, cr_tab, rgb_tab, w, h); if (filename) { f = fopen(filename, "wb"); fprintf(f, "P5\n%d %d\n%d\n", w, h * 3 / 2, 255); } else { f = stdout; } err_if(fwrite(lum_tab, 1, w * h, f) != w * h); h2 = h / 2; w2 = w / 2; cb = cb_tab; cr = cr_tab; if (filename) { for (i = 0; i < h2; i++) { err_if(fwrite(cb, 1, w2, f) != w2); err_if(fwrite(cr, 1, w2, f) != w2); cb += w2; cr += w2; } fclose(f); } else { for (i = 0; i < h2; i++) { err_if(fwrite(cb, 1, w2, f) != w2); cb += w2; } for (i = 0; i < h2; i++) { err_if(fwrite(cr, 1, w2, f) != w2); cr += w2; } } free(lum_tab); free(cb_tab); free(cr_tab); } static unsigned char *rgb_tab; static int width, height, wrap; static void put_pixel(int x, int y, int r, int g, int b) { unsigned char *p; if (x < 0 || x >= width || y < 0 || y >= height) return; p = rgb_tab + y * wrap + x * 3; p[0] = r; p[1] = g; p[2] = b; }