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comparison Core/ImageFormats/PngReader.cpp @ 799:777b6b694da6

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rename folder
author Sebastien Jodogne <s.jodogne@gmail.com>
date Tue, 06 May 2014 12:55:41 +0200
parents Core/FileFormats/PngReader.cpp@e1d27ee2114a
children ecedd89055db
comparison
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798:e1d27ee2114a 799:777b6b694da6
1 /**
2 * Orthanc - A Lightweight, RESTful DICOM Store
3 * Copyright (C) 2012-2014 Medical Physics Department, CHU of Liege,
4 * Belgium
5 *
6 * This program is free software: you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation, either version 3 of the
9 * License, or (at your option) any later version.
10 *
11 * In addition, as a special exception, the copyright holders of this
12 * program give permission to link the code of its release with the
13 * OpenSSL project's "OpenSSL" library (or with modified versions of it
14 * that use the same license as the "OpenSSL" library), and distribute
15 * the linked executables. You must obey the GNU General Public License
16 * in all respects for all of the code used other than "OpenSSL". If you
17 * modify file(s) with this exception, you may extend this exception to
18 * your version of the file(s), but you are not obligated to do so. If
19 * you do not wish to do so, delete this exception statement from your
20 * version. If you delete this exception statement from all source files
21 * in the program, then also delete it here.
22 *
23 * This program is distributed in the hope that it will be useful, but
24 * WITHOUT ANY WARRANTY; without even the implied warranty of
25 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
26 * General Public License for more details.
27 *
28 * You should have received a copy of the GNU General Public License
29 * along with this program. If not, see <http://www.gnu.org/licenses/>.
30 **/
31
32
33 #include "PngReader.h"
34
35 #include "../OrthancException.h"
36 #include "../Toolbox.h"
37
38 #include <png.h>
39 #include <string.h> // For memcpy()
40
41 namespace Orthanc
42 {
43 namespace
44 {
45 struct FileRabi
46 {
47 FILE* fp_;
48
49 FileRabi(const char* filename)
50 {
51 fp_ = fopen(filename, "rb");
52 if (!fp_)
53 {
54 throw OrthancException(ErrorCode_InexistentFile);
55 }
56 }
57
58 ~FileRabi()
59 {
60 if (fp_)
61 fclose(fp_);
62 }
63 };
64 }
65
66
67 struct PngReader::PngRabi
68 {
69 png_structp png_;
70 png_infop info_;
71 png_infop endInfo_;
72
73 void Destruct()
74 {
75 if (png_)
76 {
77 png_destroy_read_struct(&png_, &info_, &endInfo_);
78
79 png_ = NULL;
80 info_ = NULL;
81 endInfo_ = NULL;
82 }
83 }
84
85 PngRabi()
86 {
87 png_ = NULL;
88 info_ = NULL;
89 endInfo_ = NULL;
90
91 png_ = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
92 if (!png_)
93 {
94 throw OrthancException(ErrorCode_NotEnoughMemory);
95 }
96
97 info_ = png_create_info_struct(png_);
98 if (!info_)
99 {
100 png_destroy_read_struct(&png_, NULL, NULL);
101 throw OrthancException(ErrorCode_NotEnoughMemory);
102 }
103
104 endInfo_ = png_create_info_struct(png_);
105 if (!info_)
106 {
107 png_destroy_read_struct(&png_, &info_, NULL);
108 throw OrthancException(ErrorCode_NotEnoughMemory);
109 }
110 }
111
112 ~PngRabi()
113 {
114 Destruct();
115 }
116
117 static void MemoryCallback(png_structp png_ptr,
118 png_bytep data,
119 png_size_t size);
120 };
121
122
123 void PngReader::CheckHeader(const void* header)
124 {
125 int is_png = !png_sig_cmp((png_bytep) header, 0, 8);
126 if (!is_png)
127 {
128 throw OrthancException(ErrorCode_BadFileFormat);
129 }
130 }
131
132 PngReader::PngReader()
133 {
134 }
135
136 void PngReader::Read(PngRabi& rabi)
137 {
138 png_set_sig_bytes(rabi.png_, 8);
139
140 png_read_info(rabi.png_, rabi.info_);
141
142 png_uint_32 width, height;
143 int bit_depth, color_type, interlace_type;
144 int compression_type, filter_method;
145 // get size and bit-depth of the PNG-image
146 png_get_IHDR(rabi.png_, rabi.info_,
147 &width, &height,
148 &bit_depth, &color_type, &interlace_type,
149 &compression_type, &filter_method);
150
151 PixelFormat format;
152 unsigned int pitch;
153
154 if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth == 8)
155 {
156 format = PixelFormat_Grayscale8;
157 pitch = width;
158 }
159 else if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth == 16)
160 {
161 format = PixelFormat_Grayscale16;
162 pitch = 2 * width;
163
164 if (Toolbox::DetectEndianness() == Endianness_Little)
165 {
166 png_set_swap(rabi.png_);
167 }
168 }
169 else if (color_type == PNG_COLOR_TYPE_RGB && bit_depth == 8)
170 {
171 format = PixelFormat_RGB24;
172 pitch = 3 * width;
173 }
174 else
175 {
176 throw OrthancException(ErrorCode_NotImplemented);
177 }
178
179 data_.resize(height * pitch);
180
181 if (height == 0 || width == 0)
182 {
183 // Empty image, we are done
184 AssignEmpty(format);
185 return;
186 }
187
188 png_read_update_info(rabi.png_, rabi.info_);
189
190 std::vector<png_bytep> rows(height);
191 for (size_t i = 0; i < height; i++)
192 {
193 rows[i] = &data_[0] + i * pitch;
194 }
195
196 png_read_image(rabi.png_, &rows[0]);
197
198 AssignReadOnly(format, width, height, pitch, &data_[0]);
199 }
200
201 void PngReader::ReadFromFile(const char* filename)
202 {
203 FileRabi f(filename);
204
205 char header[8];
206 if (fread(header, 1, 8, f.fp_) != 8)
207 {
208 throw OrthancException(ErrorCode_BadFileFormat);
209 }
210
211 CheckHeader(header);
212
213 PngRabi rabi;
214
215 if (setjmp(png_jmpbuf(rabi.png_)))
216 {
217 rabi.Destruct();
218 throw OrthancException(ErrorCode_BadFileFormat);
219 }
220
221 png_init_io(rabi.png_, f.fp_);
222
223 Read(rabi);
224 }
225
226
227 namespace
228 {
229 struct MemoryBuffer
230 {
231 const uint8_t* buffer_;
232 size_t size_;
233 size_t pos_;
234 bool ok_;
235 };
236 }
237
238
239 void PngReader::PngRabi::MemoryCallback(png_structp png_ptr,
240 png_bytep outBytes,
241 png_size_t byteCountToRead)
242 {
243 MemoryBuffer* from = reinterpret_cast<MemoryBuffer*>(png_get_io_ptr(png_ptr));
244
245 if (!from->ok_)
246 {
247 return;
248 }
249
250 if (from->pos_ + byteCountToRead > from->size_)
251 {
252 from->ok_ = false;
253 return;
254 }
255
256 memcpy(outBytes, from->buffer_ + from->pos_, byteCountToRead);
257
258 from->pos_ += byteCountToRead;
259 }
260
261
262 void PngReader::ReadFromMemory(const void* buffer,
263 size_t size)
264 {
265 if (size < 8)
266 {
267 throw OrthancException(ErrorCode_BadFileFormat);
268 }
269
270 CheckHeader(buffer);
271
272 PngRabi rabi;
273
274 if (setjmp(png_jmpbuf(rabi.png_)))
275 {
276 rabi.Destruct();
277 throw OrthancException(ErrorCode_BadFileFormat);
278 }
279
280 MemoryBuffer tmp;
281 tmp.buffer_ = reinterpret_cast<const uint8_t*>(buffer) + 8; // We skip the header
282 tmp.size_ = size - 8;
283 tmp.pos_ = 0;
284 tmp.ok_ = true;
285
286 png_set_read_fn(rabi.png_, &tmp, PngRabi::MemoryCallback);
287
288 Read(rabi);
289
290 if (!tmp.ok_)
291 {
292 throw OrthancException(ErrorCode_BadFileFormat);
293 }
294 }
295
296 void PngReader::ReadFromMemory(const std::string& buffer)
297 {
298 if (buffer.size() != 0)
299 {
300 ReadFromMemory(&buffer[0], buffer.size());
301 }
302 else
303 {
304 ReadFromMemory(NULL, 0);
305 }
306 }
307 }