+++ /dev/null
-/*
-libimago - a multi-format image file input/output library.
-Copyright (C) 2010 John Tsiombikas <nuclear@member.fsf.org>
-
-This program 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 3 of the License, or
-(at your option) any later version.
-
-This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
-*/
-
-/* -- JPEG module -- */
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#ifdef WIN32
-#include <windows.h>
-#define HAVE_BOOLEAN
-#endif
-
-#include <jpeglib.h>
-#include "imago2.h"
-#include "ftype_module.h"
-
-#define INPUT_BUF_SIZE 512
-#define OUTPUT_BUF_SIZE 512
-
-/* data source manager: adapted from jdatasrc.c */
-struct src_mgr {
- struct jpeg_source_mgr pub;
-
- struct img_io *io;
- unsigned char buffer[INPUT_BUF_SIZE];
- int start_of_file;
-};
-
-/* data destination manager: adapted from jdatadst.c */
-struct dst_mgr {
- struct jpeg_destination_mgr pub;
-
- struct img_io *io;
- unsigned char buffer[OUTPUT_BUF_SIZE];
-};
-
-static int check(struct img_io *io);
-static int read(struct img_pixmap *img, struct img_io *io);
-static int write(struct img_pixmap *img, struct img_io *io);
-
-/* read source functions */
-static void init_source(j_decompress_ptr jd);
-static boolean fill_input_buffer(j_decompress_ptr jd);
-static void skip_input_data(j_decompress_ptr jd, long num_bytes);
-static void term_source(j_decompress_ptr jd);
-
-/* write destination functions */
-static void init_destination(j_compress_ptr jc);
-static boolean empty_output_buffer(j_compress_ptr jc);
-static void term_destination(j_compress_ptr jc);
-
-int img_register_jpeg(void)
-{
- static struct ftype_module mod = {".jpg", check, read, write};
- return img_register_module(&mod);
-}
-
-
-static int check(struct img_io *io)
-{
- unsigned char sig[10];
-
- long pos = io->seek(0, SEEK_CUR, io->uptr);
-
- if(io->read(sig, 10, io->uptr) < 10) {
- io->seek(pos, SEEK_SET, io->uptr);
- return -1;
- }
-
- if(memcmp(sig, "\xff\xd8\xff\xe0", 4) != 0 && memcmp(sig, "\xff\xd8\xff\xe1", 4) != 0
- && memcmp(sig, "\xff\xd8\xff\xdb", 4) != 0 && memcmp(sig + 6, "JFIF", 4) != 0) {
- io->seek(pos, SEEK_SET, io->uptr);
- return -1;
- }
- io->seek(pos, SEEK_SET, io->uptr);
- return 0;
-}
-
-static int read(struct img_pixmap *img, struct img_io *io)
-{
- int i, nlines = 0;
- struct jpeg_decompress_struct cinfo;
- struct jpeg_error_mgr jerr;
- struct src_mgr src;
- unsigned char **scanlines;
-
- io->seek(0, SEEK_CUR, io->uptr);
-
- cinfo.err = jpeg_std_error(&jerr); /* XXX change... */
- jpeg_create_decompress(&cinfo);
-
- src.pub.init_source = init_source;
- src.pub.fill_input_buffer = fill_input_buffer;
- src.pub.skip_input_data = skip_input_data;
- src.pub.resync_to_restart = jpeg_resync_to_restart;
- src.pub.term_source = term_source;
- src.pub.next_input_byte = 0;
- src.pub.bytes_in_buffer = 0;
- src.io = io;
- cinfo.src = (struct jpeg_source_mgr*)&src;
-
- jpeg_read_header(&cinfo, 1);
- cinfo.out_color_space = JCS_RGB;
-
- if(img_set_pixels(img, cinfo.image_width, cinfo.image_height, IMG_FMT_RGB24, 0) == -1) {
- jpeg_destroy_decompress(&cinfo);
- return -1;
- }
-
- if(!(scanlines = malloc(img->height * sizeof *scanlines))) {
- jpeg_destroy_decompress(&cinfo);
- return -1;
- }
- scanlines[0] = img->pixels;
- for(i=1; i<img->height; i++) {
- scanlines[i] = scanlines[i - 1] + img->width * img->pixelsz;
- }
-
- jpeg_start_decompress(&cinfo);
- while(nlines < img->height) {
- int res = jpeg_read_scanlines(&cinfo, scanlines + nlines, img->height - nlines);
- nlines += res;
- }
- jpeg_finish_decompress(&cinfo);
- jpeg_destroy_decompress(&cinfo);
-
- free(scanlines);
- return 0;
-}
-
-static int write(struct img_pixmap *img, struct img_io *io)
-{
- int i, nlines = 0;
- struct jpeg_compress_struct cinfo;
- struct jpeg_error_mgr jerr;
- struct dst_mgr dest;
- struct img_pixmap tmpimg;
- unsigned char **scanlines;
-
- img_init(&tmpimg);
-
- if(img->fmt != IMG_FMT_RGB24) {
- if(img_copy(&tmpimg, img) == -1) {
- return -1;
- }
- if(img_convert(&tmpimg, IMG_FMT_RGB24) == -1) {
- img_destroy(&tmpimg);
- return -1;
- }
- img = &tmpimg;
- }
-
- if(!(scanlines = malloc(img->height * sizeof *scanlines))) {
- img_destroy(&tmpimg);
- return -1;
- }
- scanlines[0] = img->pixels;
- for(i=1; i<img->height; i++) {
- scanlines[i] = scanlines[i - 1] + img->width * img->pixelsz;
- }
-
- cinfo.err = jpeg_std_error(&jerr); /* XXX */
- jpeg_create_compress(&cinfo);
-
- dest.pub.init_destination = init_destination;
- dest.pub.empty_output_buffer = empty_output_buffer;
- dest.pub.term_destination = term_destination;
- dest.io = io;
- cinfo.dest = (struct jpeg_destination_mgr*)&dest;
-
- cinfo.image_width = img->width;
- cinfo.image_height = img->height;
- cinfo.input_components = 3;
- cinfo.in_color_space = JCS_RGB;
-
- jpeg_set_defaults(&cinfo);
-
- jpeg_start_compress(&cinfo, 1);
- while(nlines < img->height) {
- int res = jpeg_write_scanlines(&cinfo, scanlines + nlines, img->height - nlines);
- nlines += res;
- }
- jpeg_finish_compress(&cinfo);
- jpeg_destroy_compress(&cinfo);
-
- free(scanlines);
- img_destroy(&tmpimg);
- return 0;
-}
-
-/* -- read source functions --
- * the following functions are adapted from jdatasrc.c in jpeglib
- */
-static void init_source(j_decompress_ptr jd)
-{
- struct src_mgr *src = (struct src_mgr*)jd->src;
- src->start_of_file = 1;
-}
-
-static boolean fill_input_buffer(j_decompress_ptr jd)
-{
- struct src_mgr *src = (struct src_mgr*)jd->src;
- size_t nbytes;
-
- nbytes = src->io->read(src->buffer, INPUT_BUF_SIZE, src->io->uptr);
-
- if(nbytes <= 0) {
- if(src->start_of_file) {
- return 0;
- }
- /* insert a fake EOI marker */
- src->buffer[0] = 0xff;
- src->buffer[1] = JPEG_EOI;
- nbytes = 2;
- }
-
- src->pub.next_input_byte = src->buffer;
- src->pub.bytes_in_buffer = nbytes;
- src->start_of_file = 0;
- return 1;
-}
-
-static void skip_input_data(j_decompress_ptr jd, long num_bytes)
-{
- struct src_mgr *src = (struct src_mgr*)jd->src;
-
- if(num_bytes > 0) {
- while(num_bytes > (long)src->pub.bytes_in_buffer) {
- num_bytes -= (long)src->pub.bytes_in_buffer;
- fill_input_buffer(jd);
- }
- src->pub.next_input_byte += (size_t)num_bytes;
- src->pub.bytes_in_buffer -= (size_t)num_bytes;
- }
-}
-
-static void term_source(j_decompress_ptr jd)
-{
- /* nothing to see here, move along */
-}
-
-
-/* -- write destination functions --
- * the following functions are adapted from jdatadst.c in jpeglib
- */
-static void init_destination(j_compress_ptr jc)
-{
- struct dst_mgr *dest = (struct dst_mgr*)jc->dest;
-
- dest->pub.next_output_byte = dest->buffer;
- dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
-}
-
-static boolean empty_output_buffer(j_compress_ptr jc)
-{
- struct dst_mgr *dest = (struct dst_mgr*)jc->dest;
-
- if(dest->io->write(dest->buffer, OUTPUT_BUF_SIZE, dest->io->uptr) != OUTPUT_BUF_SIZE) {
- return 0;
- }
-
- dest->pub.next_output_byte = dest->buffer;
- dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
- return 1;
-}
-
-static void term_destination(j_compress_ptr jc)
-{
- struct dst_mgr *dest = (struct dst_mgr*)jc->dest;
- size_t datacount = OUTPUT_BUF_SIZE - dest->pub.free_in_buffer;
-
- /* write any remaining data in the buffer */
- if(datacount > 0) {
- dest->io->write(dest->buffer, datacount, dest->io->uptr);
- }
- /* XXX flush? ... */
-}
projects / dosdemo / blobdiff