1 /* cairo - a vector graphics library with display and print output
2 *
3 * Copyright © 2008 Adrian Johnson
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it either under the terms of the GNU Lesser General Public
7 * License version 2.1 as published by the Free Software Foundation
8 * (the "LGPL") or, at your option, under the terms of the Mozilla
9 * Public License Version 1.1 (the "MPL"). If you do not alter this
10 * notice, a recipient may use your version of this file under either
11 * the MPL or the LGPL.
12 *
13 * You should have received a copy of the LGPL along with this library
14 * in the file COPYING-LGPL-2.1; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
16 * You should have received a copy of the MPL along with this library
17 * in the file COPYING-MPL-1.1
18 *
19 * The contents of this file are subject to the Mozilla Public License
20 * Version 1.1 (the "License"); you may not use this file except in
21 * compliance with the License. You may obtain a copy of the License at
22 * http://www.mozilla.org/MPL/
23 *
24 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
25 * OF ANY KIND, either express or implied. See the LGPL or the MPL for
26 * the specific language governing rights and limitations.
27 *
28 * The Original Code is the cairo graphics library.
29 *
30 * The Initial Developer of the Original Code is Adrian Johnson.
31 *
32 * Contributor(s):
33 * Adrian Johnson <ajohnson@redneon.com>
34 */
35
36 #include "cairoint.h"
37 #include "cairo-image-info-private.h"
38
39 static uint32_t
_get_be32(const unsigned char * p)40 _get_be32 (const unsigned char *p)
41 {
42 return p[0] << 24 | p[1] << 16 | p[2] << 8 | p[3];
43 }
44
45 /* JPEG (image/jpeg)
46 *
47 * http://www.w3.org/Graphics/JPEG/itu-t81.pdf
48 */
49
50 /* Markers with no parameters. All other markers are followed by a two
51 * byte length of the parameters. */
52 #define TEM 0x01
53 #define RST_begin 0xd0
54 #define RST_end 0xd7
55 #define SOI 0xd8
56 #define EOI 0xd9
57
58 /* Start of frame markers. */
59 #define SOF0 0xc0
60 #define SOF1 0xc1
61 #define SOF2 0xc2
62 #define SOF3 0xc3
63 #define SOF5 0xc5
64 #define SOF6 0xc6
65 #define SOF7 0xc7
66 #define SOF9 0xc9
67 #define SOF10 0xca
68 #define SOF11 0xcb
69 #define SOF13 0xcd
70 #define SOF14 0xce
71 #define SOF15 0xcf
72
73 static const unsigned char *
_jpeg_skip_segment(const unsigned char * p)74 _jpeg_skip_segment (const unsigned char *p)
75 {
76 int len;
77
78 p++;
79 len = (p[0] << 8) | p[1];
80
81 return p + len;
82 }
83
84 static void
_jpeg_extract_info(cairo_image_info_t * info,const unsigned char * p)85 _jpeg_extract_info (cairo_image_info_t *info, const unsigned char *p)
86 {
87 info->width = (p[6] << 8) + p[7];
88 info->height = (p[4] << 8) + p[5];
89 info->num_components = p[8];
90 info->bits_per_component = p[3];
91 }
92
93 cairo_int_status_t
_cairo_image_info_get_jpeg_info(cairo_image_info_t * info,const unsigned char * data,long length)94 _cairo_image_info_get_jpeg_info (cairo_image_info_t *info,
95 const unsigned char *data,
96 long length)
97 {
98 const unsigned char *p = data;
99
100 while (p + 1 < data + length) {
101 if (*p != 0xff)
102 return CAIRO_INT_STATUS_UNSUPPORTED;
103 p++;
104
105 switch (*p) {
106 /* skip fill bytes */
107 case 0xff:
108 p++;
109 break;
110
111 case TEM:
112 case SOI:
113 case EOI:
114 p++;
115 break;
116
117 case SOF0:
118 case SOF1:
119 case SOF2:
120 case SOF3:
121 case SOF5:
122 case SOF6:
123 case SOF7:
124 case SOF9:
125 case SOF10:
126 case SOF11:
127 case SOF13:
128 case SOF14:
129 case SOF15:
130 /* Start of frame found. Extract the image parameters. */
131 if (p + 8 > data + length)
132 return CAIRO_INT_STATUS_UNSUPPORTED;
133
134 _jpeg_extract_info (info, p);
135 return CAIRO_STATUS_SUCCESS;
136
137 default:
138 if (*p >= RST_begin && *p <= RST_end) {
139 p++;
140 break;
141 }
142
143 if (p + 2 > data + length)
144 return CAIRO_INT_STATUS_UNSUPPORTED;
145
146 p = _jpeg_skip_segment (p);
147 break;
148 }
149 }
150
151 return CAIRO_STATUS_SUCCESS;
152 }
153
154 /* JPEG 2000 (image/jp2)
155 *
156 * http://www.jpeg.org/public/15444-1annexi.pdf
157 */
158
159 #define JPX_FILETYPE 0x66747970
160 #define JPX_JP2_HEADER 0x6A703268
161 #define JPX_IMAGE_HEADER 0x69686472
162
163 static const unsigned char _jpx_signature[] = {
164 0x00, 0x00, 0x00, 0x0c, 0x6a, 0x50, 0x20, 0x20, 0x0d, 0x0a, 0x87, 0x0a
165 };
166
167 static const unsigned char *
_jpx_next_box(const unsigned char * p)168 _jpx_next_box (const unsigned char *p)
169 {
170 return p + _get_be32 (p);
171 }
172
173 static const unsigned char *
_jpx_get_box_contents(const unsigned char * p)174 _jpx_get_box_contents (const unsigned char *p)
175 {
176 return p + 8;
177 }
178
179 static cairo_bool_t
_jpx_match_box(const unsigned char * p,const unsigned char * end,uint32_t type)180 _jpx_match_box (const unsigned char *p, const unsigned char *end, uint32_t type)
181 {
182 uint32_t length;
183
184 if (p + 8 < end) {
185 length = _get_be32 (p);
186 if (_get_be32 (p + 4) == type && p + length < end)
187 return TRUE;
188 }
189
190 return FALSE;
191 }
192
193 static const unsigned char *
_jpx_find_box(const unsigned char * p,const unsigned char * end,uint32_t type)194 _jpx_find_box (const unsigned char *p, const unsigned char *end, uint32_t type)
195 {
196 while (p < end) {
197 if (_jpx_match_box (p, end, type))
198 return p;
199 p = _jpx_next_box (p);
200 }
201
202 return NULL;
203 }
204
205 static void
_jpx_extract_info(const unsigned char * p,cairo_image_info_t * info)206 _jpx_extract_info (const unsigned char *p, cairo_image_info_t *info)
207 {
208 info->height = _get_be32 (p);
209 info->width = _get_be32 (p + 4);
210 info->num_components = (p[8] << 8) + p[9];
211 info->bits_per_component = p[10];
212 }
213
214 cairo_int_status_t
_cairo_image_info_get_jpx_info(cairo_image_info_t * info,const unsigned char * data,unsigned long length)215 _cairo_image_info_get_jpx_info (cairo_image_info_t *info,
216 const unsigned char *data,
217 unsigned long length)
218 {
219 const unsigned char *p = data;
220 const unsigned char *end = data + length;
221
222 /* First 12 bytes must be the JPEG 2000 signature box. */
223 if (length < ARRAY_LENGTH(_jpx_signature) ||
224 memcmp(p, _jpx_signature, ARRAY_LENGTH(_jpx_signature)) != 0)
225 return CAIRO_INT_STATUS_UNSUPPORTED;
226
227 p += ARRAY_LENGTH(_jpx_signature);
228
229 /* Next box must be a File Type Box */
230 if (! _jpx_match_box (p, end, JPX_FILETYPE))
231 return CAIRO_INT_STATUS_UNSUPPORTED;
232
233 p = _jpx_next_box (p);
234
235 /* Locate the JP2 header box. */
236 p = _jpx_find_box (p, end, JPX_JP2_HEADER);
237 if (!p)
238 return CAIRO_INT_STATUS_UNSUPPORTED;
239
240 /* Step into the JP2 header box. First box must be the Image
241 * Header */
242 p = _jpx_get_box_contents (p);
243 if (! _jpx_match_box (p, end, JPX_IMAGE_HEADER))
244 return CAIRO_INT_STATUS_UNSUPPORTED;
245
246 /* Get the image info */
247 p = _jpx_get_box_contents (p);
248 _jpx_extract_info (p, info);
249
250 return CAIRO_STATUS_SUCCESS;
251 }
252
253 /* PNG (image/png)
254 *
255 * http://www.w3.org/TR/2003/REC-PNG-20031110/
256 */
257
258 #define PNG_IHDR 0x49484452
259
260 static const unsigned char _png_magic[8] = { 137, 80, 78, 71, 13, 10, 26, 10 };
261
262 cairo_int_status_t
_cairo_image_info_get_png_info(cairo_image_info_t * info,const unsigned char * data,unsigned long length)263 _cairo_image_info_get_png_info (cairo_image_info_t *info,
264 const unsigned char *data,
265 unsigned long length)
266 {
267 const unsigned char *p = data;
268 const unsigned char *end = data + length;
269
270 if (length < 8 || memcmp (data, _png_magic, 8) != 0)
271 return CAIRO_INT_STATUS_UNSUPPORTED;
272
273 p += 8;
274
275 /* The first chunk must be IDHR. IDHR has 13 bytes of data plus
276 * the 12 bytes of overhead for the chunk. */
277 if (p + 13 + 12 > end)
278 return CAIRO_INT_STATUS_UNSUPPORTED;
279
280 p += 4;
281 if (_get_be32 (p) != PNG_IHDR)
282 return CAIRO_INT_STATUS_UNSUPPORTED;
283
284 p += 4;
285 info->width = _get_be32 (p);
286 p += 4;
287 info->height = _get_be32 (p);
288
289 return CAIRO_STATUS_SUCCESS;
290 }
291
