Mercurial > hg > forks > geeqie

comparison src/image_load_jpeg.c @ 1901:d21859e612de

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
added custom jpeg loader
author Vladimir Nadvornik <nadvornik@suse.cz>
date Sat, 26 Mar 2011 22:03:30 +0100
parents
children 5ae882c45657
comparison
equal deleted inserted replaced
1900:6e146fa6ec29 1901:d21859e612de
1
2 #include "main.h"
3 #include "image-load.h"
4 #include "image_load_jpeg.h"
5
6 #include <setjmp.h>
7 #include <jpeglib.h>
8 #include <jerror.h>
9
10 typedef struct _ImageLoaderJpeg ImageLoaderJpeg;
11 struct _ImageLoaderJpeg {
12 ImageLoaderBackendCbAreaUpdated area_updated_cb;
13 ImageLoaderBackendCbSize size_cb;
14 ImageLoaderBackendCbAreaPrepared area_prepared_cb;
15
16 gpointer data;
17
18 GdkPixbuf *pixbuf;
19 guint requested_width;
20 guint requested_height;
21
22 gboolean abort;
23
24 };
25
26 /* error handler data */
27 struct error_handler_data {
28 struct jpeg_error_mgr pub;
29 sigjmp_buf setjmp_buffer;
30 GError **error;
31 };
32
33 /* explode gray image data from jpeg library into rgb components in pixbuf */
34 static void
35 explode_gray_into_buf (struct jpeg_decompress_struct *cinfo,
36 guchar **lines)
37 {
38 gint i, j;
39 guint w;
40
41 g_return_if_fail (cinfo != NULL);
42 g_return_if_fail (cinfo->output_components == 1);
43 g_return_if_fail (cinfo->out_color_space == JCS_GRAYSCALE);
44
45 /* Expand grey->colour. Expand from the end of the
46 * memory down, so we can use the same buffer.
47 */
48 w = cinfo->output_width;
49 for (i = cinfo->rec_outbuf_height - 1; i >= 0; i--) {
50 guchar *from, *to;
51
52 from = lines[i] + w - 1;
53 to = lines[i] + (w - 1) * 3;
54 for (j = w - 1; j >= 0; j--) {
55 to[0] = from[0];
56 to[1] = from[0];
57 to[2] = from[0];
58 to -= 3;
59 from--;
60 }
61 }
62 }
63
64
65 static void
66 convert_cmyk_to_rgb (struct jpeg_decompress_struct *cinfo,
67 guchar **lines)
68 {
69 gint i, j;
70
71 g_return_if_fail (cinfo != NULL);
72 g_return_if_fail (cinfo->output_components == 4);
73 g_return_if_fail (cinfo->out_color_space == JCS_CMYK);
74
75 for (i = cinfo->rec_outbuf_height - 1; i >= 0; i--) {
76 guchar *p;
77
78 p = lines[i];
79 for (j = 0; j < cinfo->output_width; j++) {
80 int c, m, y, k;
81 c = p[0];
82 m = p[1];
83 y = p[2];
84 k = p[3];
85 if (cinfo->saw_Adobe_marker) {
86 p[0] = k*c / 255;
87 p[1] = k*m / 255;
88 p[2] = k*y / 255;
89 }
90 else {
91 p[0] = (255 - k)*(255 - c) / 255;
92 p[1] = (255 - k)*(255 - m) / 255;
93 p[2] = (255 - k)*(255 - y) / 255;
94 }
95 p[3] = 255;
96 p += 4;
97 }
98 }
99 }
100
101
102 static gpointer image_loader_jpeg_new(ImageLoaderBackendCbAreaUpdated area_updated_cb, ImageLoaderBackendCbSize size_cb, ImageLoaderBackendCbAreaPrepared area_prepared_cb, gpointer data)
103 {
104 ImageLoaderJpeg *loader = g_new0(ImageLoaderJpeg, 1);
105
106 loader->area_updated_cb = area_updated_cb;
107 loader->size_cb = size_cb;
108 loader->area_prepared_cb = area_prepared_cb;
109 loader->data = data;
110 return (gpointer) loader;
111 }
112
113 static void
114 fatal_error_handler (j_common_ptr cinfo)
115 {
116 struct error_handler_data *errmgr;
117 char buffer[JMSG_LENGTH_MAX];
118
119 errmgr = (struct error_handler_data *) cinfo->err;
120
121 /* Create the message */
122 (* cinfo->err->format_message) (cinfo, buffer);
123
124 /* broken check for *error == NULL for robustness against
125 * crappy JPEG library
126 */
127 if (errmgr->error && *errmgr->error == NULL) {
128 g_set_error (errmgr->error,
129 GDK_PIXBUF_ERROR,
130 cinfo->err->msg_code == JERR_OUT_OF_MEMORY
131 ? GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY
132 : GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
133 _("Error interpreting JPEG image file (%s)"),
134 buffer);
135 }
136
137 siglongjmp (errmgr->setjmp_buffer, 1);
138
139 g_assert_not_reached ();
140 }
141
142 static void
143 output_message_handler (j_common_ptr cinfo)
144 {
145 /* This method keeps libjpeg from dumping crap to stderr */
146
147 /* do nothing */
148 }
149
150 static gboolean image_loader_jpeg_load (gpointer loader, const guchar *buf, gsize count, GError **error)
151 {
152 ImageLoaderJpeg *lj = (ImageLoaderJpeg *) loader;
153 struct jpeg_decompress_struct cinfo;
154 guchar *dptr;
155 guint rowstride;
156
157 struct error_handler_data jerr;
158 // stdio_src_ptr src;
159
160 /* setup error handler */
161 cinfo.err = jpeg_std_error (&jerr.pub);
162 jerr.pub.error_exit = fatal_error_handler;
163 jerr.pub.output_message = output_message_handler;
164
165 jerr.error = error;
166
167
168 if (setjmp(jerr.setjmp_buffer))
169 {
170 /* If we get here, the JPEG code has signaled an error.
171 * We need to clean up the JPEG object, close the input file, and return.
172 */
173 jpeg_destroy_decompress(&cinfo);
174 return FALSE;
175 }
176
177 jpeg_create_decompress(&cinfo);
178
179 jpeg_mem_src(&cinfo, (unsigned char *)buf, count);
180
181
182 jpeg_read_header(&cinfo, TRUE);
183
184 lj->requested_width = cinfo.image_width;
185 lj->requested_height = cinfo.image_height;
186 lj->size_cb(loader, cinfo.image_width, cinfo.image_height, lj->data);
187
188 cinfo.scale_num = 1;
189 for (cinfo.scale_denom = 2; cinfo.scale_denom <= 8; cinfo.scale_denom *= 2) {
190 jpeg_calc_output_dimensions(&cinfo);
191 if (cinfo.output_width < lj->requested_width || cinfo.output_height < lj->requested_height) {
192 cinfo.scale_denom /= 2;
193 break;
194 }
195 }
196 jpeg_calc_output_dimensions(&cinfo);
197
198 jpeg_start_decompress(&cinfo);
199
200 lj->pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB,
201 cinfo.out_color_components == 4 ? TRUE : FALSE,
202 8, cinfo.output_width, cinfo.output_height);
203
204 lj->area_prepared_cb(loader, lj->data);
205 rowstride = gdk_pixbuf_get_rowstride(lj->pixbuf);
206 dptr = gdk_pixbuf_get_pixels(lj->pixbuf);
207
208 if (!lj->pixbuf)
209 {
210 jpeg_destroy_decompress (&cinfo);
211 return 0;
212 }
213
214 while (cinfo.output_scanline < cinfo.output_height && !lj->abort)
215 {
216 guchar *lines[4];
217 guchar **lptr;
218 gint i;
219 guint scanline = cinfo.output_scanline;
220
221 lptr = lines;
222 for (i = 0; i < cinfo.rec_outbuf_height; i++)
223 {
224 *lptr++ = dptr;
225 dptr += rowstride;
226 }
227
228 jpeg_read_scanlines (&cinfo, lines, cinfo.rec_outbuf_height);
229
230 switch (cinfo.out_color_space)
231 {
232 case JCS_GRAYSCALE:
233 explode_gray_into_buf (&cinfo, lines);
234 break;
235 case JCS_RGB:
236 /* do nothing */
237 break;
238 case JCS_CMYK:
239 convert_cmyk_to_rgb (&cinfo, lines);
240 break;
241 default:
242 break;
243 }
244 lj->area_updated_cb(loader, 0, scanline, cinfo.output_width, cinfo.rec_outbuf_height, lj->data);
245 }
246
247 jpeg_finish_decompress(&cinfo);
248 jpeg_destroy_decompress(&cinfo);
249 return TRUE;
250 }
251
252 static void image_loader_jpeg_set_size(gpointer loader, int width, int height)
253 {
254 ImageLoaderJpeg *lj = (ImageLoaderJpeg *) loader;
255 lj->requested_width = width;
256 lj->requested_height = height;
257 }
258
259 static GdkPixbuf* image_loader_jpeg_get_pixbuf(gpointer loader)
260 {
261 ImageLoaderJpeg *lj = (ImageLoaderJpeg *) loader;
262 return lj->pixbuf;
263 }
264
265 static gchar* image_loader_jpeg_get_format_name(gpointer loader)
266 {
267 return g_strdup("jpeg");
268 }
269 static gchar** image_loader_jpeg_get_format_mime_types(gpointer loader)
270 {
271 static gchar *mime[] = {"image/jpeg", NULL};
272 return g_strdupv(mime);
273 }
274
275 static gboolean image_loader_jpeg_close(gpointer loader, GError **error)
276 {
277 return TRUE;
278 }
279
280 static void image_loader_jpeg_abort(gpointer loader)
281 {
282 ImageLoaderJpeg *lj = (ImageLoaderJpeg *) loader;
283 lj->abort = TRUE;
284 }
285
286 static void image_loader_jpeg_free(gpointer loader)
287 {
288 ImageLoaderJpeg *lj = (ImageLoaderJpeg *) loader;
289 if (lj->pixbuf) g_object_unref(lj->pixbuf);
290 g_free(lj);
291 }
292
293
294 void image_loader_backend_set_jpeg(ImageLoaderBackend *funcs)
295 {
296 funcs->loader_new = image_loader_jpeg_new;
297 funcs->set_size = image_loader_jpeg_set_size;
298 funcs->load = image_loader_jpeg_load;
299 funcs->write = NULL;
300 funcs->get_pixbuf = image_loader_jpeg_get_pixbuf;
301 funcs->close = image_loader_jpeg_close;
302 funcs->abort = image_loader_jpeg_abort;
303 funcs->free = image_loader_jpeg_free;
304
305 funcs->get_format_name = image_loader_jpeg_get_format_name;
306 funcs->get_format_mime_types = image_loader_jpeg_get_format_mime_types;
307 }
308
309
310