vrshoot

annotate libs/imago/file_jpeg.c @ 1:e7ca128b8713

looks nice :)
author John Tsiombikas <nuclear@member.fsf.org>
date Sun, 02 Feb 2014 00:35:22 +0200
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nuclear@0 1 /*
nuclear@0 2 libimago - a multi-format image file input/output library.
nuclear@0 3 Copyright (C) 2010 John Tsiombikas <nuclear@member.fsf.org>
nuclear@0 4
nuclear@0 5 This program is free software: you can redistribute it and/or modify
nuclear@0 6 it under the terms of the GNU Lesser General Public License as published
nuclear@0 7 by the Free Software Foundation, either version 3 of the License, or
nuclear@0 8 (at your option) any later version.
nuclear@0 9
nuclear@0 10 This program is distributed in the hope that it will be useful,
nuclear@0 11 but WITHOUT ANY WARRANTY; without even the implied warranty of
nuclear@0 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
nuclear@0 13 GNU Lesser General Public License for more details.
nuclear@0 14
nuclear@0 15 You should have received a copy of the GNU Lesser General Public License
nuclear@0 16 along with this program. If not, see <http://www.gnu.org/licenses/>.
nuclear@0 17 */
nuclear@0 18
nuclear@0 19 /* -- JPEG module -- */
nuclear@0 20
nuclear@0 21 #include <stdio.h>
nuclear@0 22 #include <stdlib.h>
nuclear@0 23 #include <string.h>
nuclear@0 24
nuclear@0 25 #ifdef WIN32
nuclear@0 26 #include <windows.h>
nuclear@0 27 #define HAVE_BOOLEAN
nuclear@0 28 #endif
nuclear@0 29
nuclear@0 30 #include <jpeglib.h>
nuclear@0 31 #include "imago2.h"
nuclear@0 32 #include "ftype_module.h"
nuclear@0 33
nuclear@0 34 #define INPUT_BUF_SIZE 512
nuclear@0 35 #define OUTPUT_BUF_SIZE 512
nuclear@0 36
nuclear@0 37 /* data source manager: adapted from jdatasrc.c */
nuclear@0 38 struct src_mgr {
nuclear@0 39 struct jpeg_source_mgr pub;
nuclear@0 40
nuclear@0 41 struct img_io *io;
nuclear@0 42 unsigned char buffer[INPUT_BUF_SIZE];
nuclear@0 43 int start_of_file;
nuclear@0 44 };
nuclear@0 45
nuclear@0 46 /* data destination manager: adapted from jdatadst.c */
nuclear@0 47 struct dst_mgr {
nuclear@0 48 struct jpeg_destination_mgr pub;
nuclear@0 49
nuclear@0 50 struct img_io *io;
nuclear@0 51 unsigned char buffer[OUTPUT_BUF_SIZE];
nuclear@0 52 };
nuclear@0 53
nuclear@0 54 static int check(struct img_io *io);
nuclear@0 55 static int read(struct img_pixmap *img, struct img_io *io);
nuclear@0 56 static int write(struct img_pixmap *img, struct img_io *io);
nuclear@0 57
nuclear@0 58 /* read source functions */
nuclear@0 59 static void init_source(j_decompress_ptr jd);
nuclear@0 60 static boolean fill_input_buffer(j_decompress_ptr jd);
nuclear@0 61 static void skip_input_data(j_decompress_ptr jd, long num_bytes);
nuclear@0 62 static void term_source(j_decompress_ptr jd);
nuclear@0 63
nuclear@0 64 /* write destination functions */
nuclear@0 65 static void init_destination(j_compress_ptr jc);
nuclear@0 66 static boolean empty_output_buffer(j_compress_ptr jc);
nuclear@0 67 static void term_destination(j_compress_ptr jc);
nuclear@0 68
nuclear@0 69 int img_register_jpeg(void)
nuclear@0 70 {
nuclear@0 71 static struct ftype_module mod = {".jpg", check, read, write};
nuclear@0 72 return img_register_module(&mod);
nuclear@0 73 }
nuclear@0 74
nuclear@0 75
nuclear@0 76 static int check(struct img_io *io)
nuclear@0 77 {
nuclear@0 78 unsigned char sig[10];
nuclear@0 79
nuclear@0 80 long pos = io->seek(0, SEEK_CUR, io->uptr);
nuclear@0 81
nuclear@0 82 if(io->read(sig, 10, io->uptr) < 10) {
nuclear@0 83 io->seek(pos, SEEK_SET, io->uptr);
nuclear@0 84 return -1;
nuclear@0 85 }
nuclear@0 86
nuclear@0 87 if(memcmp(sig, "\xff\xd8\xff\xe0", 4) != 0 && memcmp(sig, "\xff\xd8\xff\xe1", 4) != 0
nuclear@0 88 && memcmp(sig + 6, "JFIF", 4) != 0) {
nuclear@0 89 io->seek(pos, SEEK_SET, io->uptr);
nuclear@0 90 return -1;
nuclear@0 91 }
nuclear@0 92 io->seek(pos, SEEK_SET, io->uptr);
nuclear@0 93 return 0;
nuclear@0 94 }
nuclear@0 95
nuclear@0 96 static int read(struct img_pixmap *img, struct img_io *io)
nuclear@0 97 {
nuclear@0 98 int i, nlines = 0;
nuclear@0 99 struct jpeg_decompress_struct cinfo;
nuclear@0 100 struct jpeg_error_mgr jerr;
nuclear@0 101 struct src_mgr src;
nuclear@0 102 unsigned char **scanlines;
nuclear@0 103
nuclear@0 104 io->seek(0, SEEK_CUR, io->uptr);
nuclear@0 105
nuclear@0 106 cinfo.err = jpeg_std_error(&jerr); /* XXX change... */
nuclear@0 107 jpeg_create_decompress(&cinfo);
nuclear@0 108
nuclear@0 109 src.pub.init_source = init_source;
nuclear@0 110 src.pub.fill_input_buffer = fill_input_buffer;
nuclear@0 111 src.pub.skip_input_data = skip_input_data;
nuclear@0 112 src.pub.resync_to_restart = jpeg_resync_to_restart;
nuclear@0 113 src.pub.term_source = term_source;
nuclear@0 114 src.pub.next_input_byte = 0;
nuclear@0 115 src.pub.bytes_in_buffer = 0;
nuclear@0 116 src.io = io;
nuclear@0 117 cinfo.src = (struct jpeg_source_mgr*)&src;
nuclear@0 118
nuclear@0 119 jpeg_read_header(&cinfo, 1);
nuclear@0 120 cinfo.out_color_space = JCS_RGB;
nuclear@0 121
nuclear@0 122 if(img_set_pixels(img, cinfo.image_width, cinfo.image_height, IMG_FMT_RGB24, 0) == -1) {
nuclear@0 123 jpeg_destroy_decompress(&cinfo);
nuclear@0 124 return -1;
nuclear@0 125 }
nuclear@0 126
nuclear@0 127 if(!(scanlines = malloc(img->height * sizeof *scanlines))) {
nuclear@0 128 jpeg_destroy_decompress(&cinfo);
nuclear@0 129 return -1;
nuclear@0 130 }
nuclear@0 131 scanlines[0] = img->pixels;
nuclear@0 132 for(i=1; i<img->height; i++) {
nuclear@0 133 scanlines[i] = scanlines[i - 1] + img->width * img->pixelsz;
nuclear@0 134 }
nuclear@0 135
nuclear@0 136 jpeg_start_decompress(&cinfo);
nuclear@0 137 while(nlines < img->height) {
nuclear@0 138 int res = jpeg_read_scanlines(&cinfo, scanlines + nlines, img->height - nlines);
nuclear@0 139 nlines += res;
nuclear@0 140 }
nuclear@0 141 jpeg_finish_decompress(&cinfo);
nuclear@0 142 jpeg_destroy_decompress(&cinfo);
nuclear@0 143
nuclear@0 144 free(scanlines);
nuclear@0 145 return 0;
nuclear@0 146 }
nuclear@0 147
nuclear@0 148 static int write(struct img_pixmap *img, struct img_io *io)
nuclear@0 149 {
nuclear@0 150 int i, nlines = 0;
nuclear@0 151 struct jpeg_compress_struct cinfo;
nuclear@0 152 struct jpeg_error_mgr jerr;
nuclear@0 153 struct dst_mgr dest;
nuclear@0 154 struct img_pixmap tmpimg;
nuclear@0 155 unsigned char **scanlines;
nuclear@0 156
nuclear@0 157 img_init(&tmpimg);
nuclear@0 158
nuclear@0 159 if(img->fmt != IMG_FMT_RGB24) {
nuclear@0 160 if(img_copy(&tmpimg, img) == -1) {
nuclear@0 161 return -1;
nuclear@0 162 }
nuclear@0 163 if(img_convert(&tmpimg, IMG_FMT_RGB24) == -1) {
nuclear@0 164 img_destroy(&tmpimg);
nuclear@0 165 return -1;
nuclear@0 166 }
nuclear@0 167 img = &tmpimg;
nuclear@0 168 }
nuclear@0 169
nuclear@0 170 if(!(scanlines = malloc(img->height * sizeof *scanlines))) {
nuclear@0 171 img_destroy(&tmpimg);
nuclear@0 172 return -1;
nuclear@0 173 }
nuclear@0 174 scanlines[0] = img->pixels;
nuclear@0 175 for(i=1; i<img->height; i++) {
nuclear@0 176 scanlines[i] = scanlines[i - 1] + img->width * img->pixelsz;
nuclear@0 177 }
nuclear@0 178
nuclear@0 179 cinfo.err = jpeg_std_error(&jerr); /* XXX */
nuclear@0 180 jpeg_create_compress(&cinfo);
nuclear@0 181
nuclear@0 182 dest.pub.init_destination = init_destination;
nuclear@0 183 dest.pub.empty_output_buffer = empty_output_buffer;
nuclear@0 184 dest.pub.term_destination = term_destination;
nuclear@0 185 dest.io = io;
nuclear@0 186 cinfo.dest = (struct jpeg_destination_mgr*)&dest;
nuclear@0 187
nuclear@0 188 cinfo.image_width = img->width;
nuclear@0 189 cinfo.image_height = img->height;
nuclear@0 190 cinfo.input_components = 3;
nuclear@0 191 cinfo.in_color_space = JCS_RGB;
nuclear@0 192
nuclear@0 193 jpeg_set_defaults(&cinfo);
nuclear@0 194
nuclear@0 195 jpeg_start_compress(&cinfo, 1);
nuclear@0 196 while(nlines < img->height) {
nuclear@0 197 int res = jpeg_write_scanlines(&cinfo, scanlines + nlines, img->height - nlines);
nuclear@0 198 nlines += res;
nuclear@0 199 }
nuclear@0 200 jpeg_finish_compress(&cinfo);
nuclear@0 201 jpeg_destroy_compress(&cinfo);
nuclear@0 202
nuclear@0 203 free(scanlines);
nuclear@0 204 img_destroy(&tmpimg);
nuclear@0 205 return 0;
nuclear@0 206 }
nuclear@0 207
nuclear@0 208 /* -- read source functions --
nuclear@0 209 * the following functions are adapted from jdatasrc.c in jpeglib
nuclear@0 210 */
nuclear@0 211 static void init_source(j_decompress_ptr jd)
nuclear@0 212 {
nuclear@0 213 struct src_mgr *src = (struct src_mgr*)jd->src;
nuclear@0 214 src->start_of_file = 1;
nuclear@0 215 }
nuclear@0 216
nuclear@0 217 static boolean fill_input_buffer(j_decompress_ptr jd)
nuclear@0 218 {
nuclear@0 219 struct src_mgr *src = (struct src_mgr*)jd->src;
nuclear@0 220 size_t nbytes;
nuclear@0 221
nuclear@0 222 nbytes = src->io->read(src->buffer, INPUT_BUF_SIZE, src->io->uptr);
nuclear@0 223
nuclear@0 224 if(nbytes <= 0) {
nuclear@0 225 if(src->start_of_file) {
nuclear@0 226 return 0;
nuclear@0 227 }
nuclear@0 228 /* insert a fake EOI marker */
nuclear@0 229 src->buffer[0] = 0xff;
nuclear@0 230 src->buffer[1] = JPEG_EOI;
nuclear@0 231 nbytes = 2;
nuclear@0 232 }
nuclear@0 233
nuclear@0 234 src->pub.next_input_byte = src->buffer;
nuclear@0 235 src->pub.bytes_in_buffer = nbytes;
nuclear@0 236 src->start_of_file = 0;
nuclear@0 237 return 1;
nuclear@0 238 }
nuclear@0 239
nuclear@0 240 static void skip_input_data(j_decompress_ptr jd, long num_bytes)
nuclear@0 241 {
nuclear@0 242 struct src_mgr *src = (struct src_mgr*)jd->src;
nuclear@0 243
nuclear@0 244 if(num_bytes > 0) {
nuclear@0 245 while(num_bytes > (long)src->pub.bytes_in_buffer) {
nuclear@0 246 num_bytes -= (long)src->pub.bytes_in_buffer;
nuclear@0 247 fill_input_buffer(jd);
nuclear@0 248 }
nuclear@0 249 src->pub.next_input_byte += (size_t)num_bytes;
nuclear@0 250 src->pub.bytes_in_buffer -= (size_t)num_bytes;
nuclear@0 251 }
nuclear@0 252 }
nuclear@0 253
nuclear@0 254 static void term_source(j_decompress_ptr jd)
nuclear@0 255 {
nuclear@0 256 /* nothing to see here, move along */
nuclear@0 257 }
nuclear@0 258
nuclear@0 259
nuclear@0 260 /* -- write destination functions --
nuclear@0 261 * the following functions are adapted from jdatadst.c in jpeglib
nuclear@0 262 */
nuclear@0 263 static void init_destination(j_compress_ptr jc)
nuclear@0 264 {
nuclear@0 265 struct dst_mgr *dest = (struct dst_mgr*)jc->dest;
nuclear@0 266
nuclear@0 267 dest->pub.next_output_byte = dest->buffer;
nuclear@0 268 dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
nuclear@0 269 }
nuclear@0 270
nuclear@0 271 static boolean empty_output_buffer(j_compress_ptr jc)
nuclear@0 272 {
nuclear@0 273 struct dst_mgr *dest = (struct dst_mgr*)jc->dest;
nuclear@0 274
nuclear@0 275 if(dest->io->write(dest->buffer, OUTPUT_BUF_SIZE, dest->io->uptr) != OUTPUT_BUF_SIZE) {
nuclear@0 276 return 0;
nuclear@0 277 }
nuclear@0 278
nuclear@0 279 dest->pub.next_output_byte = dest->buffer;
nuclear@0 280 dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
nuclear@0 281 return 1;
nuclear@0 282 }
nuclear@0 283
nuclear@0 284 static void term_destination(j_compress_ptr jc)
nuclear@0 285 {
nuclear@0 286 struct dst_mgr *dest = (struct dst_mgr*)jc->dest;
nuclear@0 287 size_t datacount = OUTPUT_BUF_SIZE - dest->pub.free_in_buffer;
nuclear@0 288
nuclear@0 289 /* write any remaining data in the buffer */
nuclear@0 290 if(datacount > 0) {
nuclear@0 291 dest->io->write(dest->buffer, datacount, dest->io->uptr);
nuclear@0 292 }
nuclear@0 293 /* XXX flush? ... */
nuclear@0 294 }