jpg2ff.c (1925B)
1 /* See LICENSE file for copyright and license details. */ 2 #include <arpa/inet.h> 3 4 #include <errno.h> 5 #include <stdint.h> 6 #include <stdio.h> 7 #include <stdlib.h> 8 #include <string.h> 9 10 #include <jpeglib.h> 11 12 #include "util.h" 13 14 static void 15 jpeg_error(j_common_ptr js) 16 { 17 fprintf(stderr, "%s: libjpeg: ", argv0); 18 (*js->err->output_message)(js); 19 exit(1); 20 } 21 22 static void 23 jpeg_setup_reader(struct jpeg_decompress_struct *s, struct jpeg_error_mgr *e, 24 uint32_t *w, uint32_t *h) 25 { 26 jpeg_create_decompress(s); 27 e->error_exit = jpeg_error; 28 s->err = jpeg_std_error(e); 29 30 jpeg_stdio_src(s, stdin); 31 jpeg_read_header(s, 1); 32 *w = s->image_width; 33 *h = s->image_height; 34 s->output_components = 3; /* color components per pixel */ 35 s->out_color_space = JCS_RGB; /* input color space */ 36 37 jpeg_start_decompress(s); 38 } 39 40 static void 41 usage(void) 42 { 43 die("usage: %s", argv0); 44 } 45 46 int 47 main(int argc, char *argv[]) 48 { 49 struct jpeg_decompress_struct js; 50 struct jpeg_error_mgr jerr; 51 uint32_t width, height; 52 uint16_t *row; 53 uint8_t *rowin; 54 size_t rowlen, i; 55 56 /* arguments */ 57 argv0 = argv[0], argc--, argv++; 58 59 if (argc) { 60 usage(); 61 } 62 63 /* prepare */ 64 jpeg_setup_reader(&js, &jerr, &width, &height); 65 row = ereallocarray(NULL, width, (sizeof("RGBA") - 1) * sizeof(uint16_t)); 66 rowlen = width * (sizeof("RGBA") - 1); 67 rowin = ereallocarray(NULL, width, (sizeof("RGB") - 1) * sizeof(uint8_t)); 68 69 /* write data */ 70 ff_write_header(width, height); 71 72 while (js.output_scanline < js.output_height) { 73 jpeg_read_scanlines(&js, &rowin, 1); 74 75 for (i = 0; i < width; ++i) { 76 row[4 * i + 0] = htons(rowin[3 * i + 0] * 257); 77 row[4 * i + 1] = htons(rowin[3 * i + 1] * 257); 78 row[4 * i + 2] = htons(rowin[3 * i + 2] * 257); 79 row[4 * i + 3] = htons(65535); 80 } 81 82 efwrite(row, sizeof(uint16_t), rowlen, stdout); 83 } 84 85 /* clean up */ 86 jpeg_finish_decompress(&js); 87 jpeg_destroy_decompress(&js); 88 89 return fshut(stdout, "<stdout>"); 90 }