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comparison e2gallerypro/e2upload/Backend/Assets/getid3/module.graphic.png.php @ 3:3f6b44aa6b35 judyates

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[svn r4] added ability to buy stuff, from a Prints page, but it doesn't work well with the css, and it also has not been fitted into the perl make system.
author rlm
date Mon, 22 Feb 2010 08:02:39 -0500
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2:670229c4eb4b 3:3f6b44aa6b35
1 <?php
2 // +----------------------------------------------------------------------+
3 // | PHP version 5 |
4 // +----------------------------------------------------------------------+
5 // | Copyright (c) 2002-2006 James Heinrich, Allan Hansen |
6 // +----------------------------------------------------------------------+
7 // | This source file is subject to version 2 of the GPL license, |
8 // | that is bundled with this package in the file license.txt and is |
9 // | available through the world-wide-web at the following url: |
10 // | http://www.gnu.org/copyleft/gpl.html |
11 // +----------------------------------------------------------------------+
12 // | getID3() - http://getid3.sourceforge.net or http://www.getid3.org |
13 // +----------------------------------------------------------------------+
14 // | Authors: James Heinrich <infoØgetid3*org> |
15 // | Allan Hansen <ahØartemis*dk> |
16 // +----------------------------------------------------------------------+
17 // | module.graphic.png.php |
18 // | Module for analyzing PNG graphic files. |
19 // | dependencies: zlib support in PHP (optional) |
20 // +----------------------------------------------------------------------+
21 //
22 // $Id: module.graphic.png.php,v 1.4 2006/11/02 10:48:02 ah Exp $
23
24
25
26 class getid3_png extends getid3_handler
27 {
28
29 public function Analyze() {
30
31 $getid3 = $this->getid3;
32
33 $getid3->info['png'] = array ();
34 $info_png = &$getid3->info['png'];
35
36 $getid3->info['fileformat'] = 'png';
37 $getid3->info['video']['dataformat'] = 'png';
38 $getid3->info['video']['lossless'] = false;
39
40 fseek($getid3->fp, $getid3->info['avdataoffset'], SEEK_SET);
41 $png_filedata = fread($getid3->fp, getid3::FREAD_BUFFER_SIZE);
42
43 // Magic bytes "\x89\x50\x4E\x47\x0D\x0A\x1A\x0A"
44
45 $offset = 8;
46
47 while (((ftell($getid3->fp) - (strlen($png_filedata) - $offset)) < $getid3->info['filesize'])) {
48
49 $chunk['data_length'] = getid3_lib::BigEndian2Int(substr($png_filedata, $offset, 4));
50 $offset += 4;
51 while (((strlen($png_filedata) - $offset) < ($chunk['data_length'] + 4)) && (ftell($getid3->fp) < $getid3->info['filesize'])) {
52 $png_filedata .= fread($getid3->fp, getid3::FREAD_BUFFER_SIZE);
53 }
54
55 $chunk['type_text'] = substr($png_filedata, $offset, 4);
56 $chunk['type_raw'] = getid3_lib::BigEndian2Int($chunk['type_text']);
57 $offset += 4;
58
59 $chunk['data'] = substr($png_filedata, $offset, $chunk['data_length']);
60 $offset += $chunk['data_length'];
61
62 $chunk['crc'] = getid3_lib::BigEndian2Int(substr($png_filedata, $offset, 4));
63 $offset += 4;
64
65 $chunk['flags']['ancilliary'] = (bool)($chunk['type_raw'] & 0x20000000);
66 $chunk['flags']['private'] = (bool)($chunk['type_raw'] & 0x00200000);
67 $chunk['flags']['reserved'] = (bool)($chunk['type_raw'] & 0x00002000);
68 $chunk['flags']['safe_to_copy'] = (bool)($chunk['type_raw'] & 0x00000020);
69
70 // shortcut
71 $info_png[$chunk['type_text']] = array ();
72 $info_png_chunk_type_text = &$info_png[$chunk['type_text']];
73
74 switch ($chunk['type_text']) {
75
76 case 'IHDR': // Image Header
77 $info_png_chunk_type_text['header'] = $chunk;
78 $info_png_chunk_type_text['width'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 4));
79 $info_png_chunk_type_text['height'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 4, 4));
80
81 getid3_lib::ReadSequence('BigEndian2Int', $info_png_chunk_type_text['raw'], $chunk['data'], 8,
82 array (
83 'bit_depth' => 1,
84 'color_type' => 1,
85 'compression_method' => 1,
86 'filter_method' => 1,
87 'interlace_method' => 1
88 )
89 );
90
91 $info_png_chunk_type_text['compression_method_text'] = getid3_png::PNGcompressionMethodLookup($info_png_chunk_type_text['raw']['compression_method']);
92 $info_png_chunk_type_text['color_type']['palette'] = (bool)($info_png_chunk_type_text['raw']['color_type'] & 0x01);
93 $info_png_chunk_type_text['color_type']['true_color'] = (bool)($info_png_chunk_type_text['raw']['color_type'] & 0x02);
94 $info_png_chunk_type_text['color_type']['alpha'] = (bool)($info_png_chunk_type_text['raw']['color_type'] & 0x04);
95
96 $getid3->info['video']['resolution_x'] = $info_png_chunk_type_text['width'];
97 $getid3->info['video']['resolution_y'] = $info_png_chunk_type_text['height'];
98
99 $getid3->info['video']['bits_per_sample'] = getid3_png::IHDRcalculateBitsPerSample($info_png_chunk_type_text['raw']['color_type'], $info_png_chunk_type_text['raw']['bit_depth']);
100 break;
101
102
103 case 'PLTE': // Palette
104 $info_png_chunk_type_text['header'] = $chunk;
105 $palette_offset = 0;
106 for ($i = 0; $i <= 255; $i++) {
107 $red = @getid3_lib::BigEndian2Int($chunk['data']{$palette_offset++});
108 $green = @getid3_lib::BigEndian2Int($chunk['data']{$palette_offset++});
109 $blue = @getid3_lib::BigEndian2Int($chunk['data']{$palette_offset++});
110 $info_png_chunk_type_text[$i] = (($red << 16) | ($green << 8) | ($blue));
111 }
112 break;
113
114
115 case 'tRNS': // Transparency
116 $info_png_chunk_type_text['header'] = $chunk;
117 switch ($info_png['IHDR']['raw']['color_type']) {
118 case 0:
119 $info_png_chunk_type_text['transparent_color_gray'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 2));
120 break;
121
122 case 2:
123 $info_png_chunk_type_text['transparent_color_red'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 2));
124 $info_png_chunk_type_text['transparent_color_green'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 2, 2));
125 $info_png_chunk_type_text['transparent_color_blue'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 4, 2));
126 break;
127
128 case 3:
129 for ($i = 0; $i < strlen($chunk['data']); $i++) {
130 $info_png_chunk_type_text['palette_opacity'][$i] = getid3_lib::BigEndian2Int($chunk['data'][$i]);
131 }
132 break;
133
134 case 4:
135 case 6:
136 throw new getid3_exception('Invalid color_type in tRNS chunk: '.$info_png['IHDR']['raw']['color_type']);
137
138 default:
139 $getid3->warning('Unhandled color_type in tRNS chunk: '.$info_png['IHDR']['raw']['color_type']);
140 break;
141 }
142 break;
143
144
145 case 'gAMA': // Image Gamma
146 $info_png_chunk_type_text['header'] = $chunk;
147 $info_png_chunk_type_text['gamma'] = getid3_lib::BigEndian2Int($chunk['data']) / 100000;
148 break;
149
150
151 case 'cHRM': // Primary Chromaticities
152 $info_png_chunk_type_text['header'] = $chunk;
153 $info_png_chunk_type_text['white_x'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 4)) / 100000;
154 $info_png_chunk_type_text['white_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 4, 4)) / 100000;
155 $info_png_chunk_type_text['red_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 8, 4)) / 100000;
156 $info_png_chunk_type_text['red_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 12, 4)) / 100000;
157 $info_png_chunk_type_text['green_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 16, 4)) / 100000;
158 $info_png_chunk_type_text['green_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 20, 4)) / 100000;
159 $info_png_chunk_type_text['blue_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 24, 4)) / 100000;
160 $info_png_chunk_type_text['blue_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 28, 4)) / 100000;
161 break;
162
163
164 case 'sRGB': // Standard RGB Color Space
165 $info_png_chunk_type_text['header'] = $chunk;
166 $info_png_chunk_type_text['reindering_intent'] = getid3_lib::BigEndian2Int($chunk['data']);
167 $info_png_chunk_type_text['reindering_intent_text'] = getid3_png::PNGsRGBintentLookup($info_png_chunk_type_text['reindering_intent']);
168 break;
169
170
171 case 'iCCP': // Embedded ICC Profile
172 $info_png_chunk_type_text['header'] = $chunk;
173 list($profilename, $compressiondata) = explode("\x00", $chunk['data'], 2);
174 $info_png_chunk_type_text['profile_name'] = $profilename;
175 $info_png_chunk_type_text['compression_method'] = getid3_lib::BigEndian2Int($compressiondata[0]);
176 $info_png_chunk_type_text['compression_profile'] = substr($compressiondata, 1);
177 $info_png_chunk_type_text['compression_method_text'] = getid3_png::PNGcompressionMethodLookup($info_png_chunk_type_text['compression_method']);
178 break;
179
180
181 case 'tEXt': // Textual Data
182 $info_png_chunk_type_text['header'] = $chunk;
183 list($keyword, $text) = explode("\x00", $chunk['data'], 2);
184 $info_png_chunk_type_text['keyword'] = $keyword;
185 $info_png_chunk_type_text['text'] = $text;
186
187 $info_png['comments'][$info_png_chunk_type_text['keyword']][] = $info_png_chunk_type_text['text'];
188 break;
189
190
191 case 'zTXt': // Compressed Textual Data
192 $info_png_chunk_type_text['header'] = $chunk;
193 list($keyword, $otherdata) = explode("\x00", $chunk['data'], 2);
194 $info_png_chunk_type_text['keyword'] = $keyword;
195 $info_png_chunk_type_text['compression_method'] = getid3_lib::BigEndian2Int(substr($otherdata, 0, 1));
196 $info_png_chunk_type_text['compressed_text'] = substr($otherdata, 1);
197 $info_png_chunk_type_text['compression_method_text'] = getid3_png::PNGcompressionMethodLookup($info_png_chunk_type_text['compression_method']);
198
199 if ($info_png_chunk_type_text['compression_method'] != 0) {
200 // unknown compression method
201 break;
202 }
203
204 if (function_exists('gzuncompress')) {
205 $info_png_chunk_type_text['text'] = gzuncompress($info_png_chunk_type_text['compressed_text']);
206 }
207 else {
208 if (!@$this->zlib_warning) {
209 $getid3->warning('PHP does not have --with-zlib support - cannot gzuncompress()');
210 }
211 $this->zlib_warning = true;
212 }
213
214
215 if (isset($info_png_chunk_type_text['text'])) {
216 $info_png['comments'][$info_png_chunk_type_text['keyword']][] = $info_png_chunk_type_text['text'];
217 }
218 break;
219
220
221 case 'iTXt': // International Textual Data
222 $info_png_chunk_type_text['header'] = $chunk;
223 list($keyword, $otherdata) = explode("\x00", $chunk['data'], 2);
224 $info_png_chunk_type_text['keyword'] = $keyword;
225 $info_png_chunk_type_text['compression'] = (bool)getid3_lib::BigEndian2Int(substr($otherdata, 0, 1));
226 $info_png_chunk_type_text['compression_method'] = getid3_lib::BigEndian2Int($otherdata[1]);
227 $info_png_chunk_type_text['compression_method_text'] = getid3_png::PNGcompressionMethodLookup($info_png_chunk_type_text['compression_method']);
228 list($languagetag, $translatedkeyword, $text) = explode("\x00", substr($otherdata, 2), 3);
229 $info_png_chunk_type_text['language_tag'] = $languagetag;
230 $info_png_chunk_type_text['translated_keyword'] = $translatedkeyword;
231
232 if ($info_png_chunk_type_text['compression']) {
233
234 switch ($info_png_chunk_type_text['compression_method']) {
235 case 0:
236 if (function_exists('gzuncompress')) {
237 $info_png_chunk_type_text['text'] = gzuncompress($text);
238 }
239 else {
240 if (!@$this->zlib_warning) {
241 $getid3->warning('PHP does not have --with-zlib support - cannot gzuncompress()');
242 }
243 $this->zlib_warning = true;
244 }
245 break;
246
247 default:
248 // unknown compression method
249 break;
250 }
251
252 } else {
253
254 $info_png_chunk_type_text['text'] = $text;
255
256 }
257
258 if (isset($info_png_chunk_type_text['text'])) {
259 $info_png['comments'][$info_png_chunk_type_text['keyword']][] = $info_png_chunk_type_text['text'];
260 }
261 break;
262
263
264 case 'bKGD': // Background Color
265 $info_png_chunk_type_text['header'] = $chunk;
266 switch ($info_png['IHDR']['raw']['color_type']) {
267 case 0:
268 case 4:
269 $info_png_chunk_type_text['background_gray'] = getid3_lib::BigEndian2Int($chunk['data']);
270 break;
271
272 case 2:
273 case 6:
274 $info_png_chunk_type_text['background_red'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0 * $info_png['IHDR']['raw']['bit_depth'], $info_png['IHDR']['raw']['bit_depth']));
275 $info_png_chunk_type_text['background_green'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 1 * $info_png['IHDR']['raw']['bit_depth'], $info_png['IHDR']['raw']['bit_depth']));
276 $info_png_chunk_type_text['background_blue'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 2 * $info_png['IHDR']['raw']['bit_depth'], $info_png['IHDR']['raw']['bit_depth']));
277 break;
278
279 case 3:
280 $info_png_chunk_type_text['background_index'] = getid3_lib::BigEndian2Int($chunk['data']);
281 break;
282
283 default:
284 break;
285 }
286 break;
287
288
289 case 'pHYs': // Physical Pixel Dimensions
290 $info_png_chunk_type_text['header'] = $chunk;
291 $info_png_chunk_type_text['pixels_per_unit_x'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 4));
292 $info_png_chunk_type_text['pixels_per_unit_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 4, 4));
293 $info_png_chunk_type_text['unit_specifier'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 8, 1));
294 $info_png_chunk_type_text['unit'] = getid3_png::PNGpHYsUnitLookup($info_png_chunk_type_text['unit_specifier']);
295 break;
296
297
298 case 'sBIT': // Significant Bits
299 $info_png_chunk_type_text['header'] = $chunk;
300 switch ($info_png['IHDR']['raw']['color_type']) {
301 case 0:
302 $info_png_chunk_type_text['significant_bits_gray'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 1));
303 break;
304
305 case 2:
306 case 3:
307 $info_png_chunk_type_text['significant_bits_red'] = getid3_lib::BigEndian2Int($chunk['data'][0]);
308 $info_png_chunk_type_text['significant_bits_green'] = getid3_lib::BigEndian2Int($chunk['data'][1]);
309 $info_png_chunk_type_text['significant_bits_blue'] = getid3_lib::BigEndian2Int($chunk['data'][2]);
310 break;
311
312 case 4:
313 $info_png_chunk_type_text['significant_bits_gray'] = getid3_lib::BigEndian2Int($chunk['data'][0]);
314 $info_png_chunk_type_text['significant_bits_alpha'] = getid3_lib::BigEndian2Int($chunk['data'][1]);
315 break;
316
317 case 6:
318 $info_png_chunk_type_text['significant_bits_red'] = getid3_lib::BigEndian2Int($chunk['data'][0]);
319 $info_png_chunk_type_text['significant_bits_green'] = getid3_lib::BigEndian2Int($chunk['data'][1]);
320 $info_png_chunk_type_text['significant_bits_blue'] = getid3_lib::BigEndian2Int($chunk['data'][2]);
321 $info_png_chunk_type_text['significant_bits_alpha'] = getid3_lib::BigEndian2Int($chunk['data'][3]);
322 break;
323
324 default:
325 break;
326 }
327 break;
328
329
330 case 'sPLT': // Suggested Palette
331 $info_png_chunk_type_text['header'] = $chunk;
332
333 list($palettename, $otherdata) = explode("\x00", $chunk['data'], 2);
334 $info_png_chunk_type_text['palette_name'] = $palettename;
335
336 $info_png_chunk_type_text['sample_depth_bits'] = getid3_lib::BigEndian2Int($otherdata[0]);
337 $info_png_chunk_type_text['sample_depth_bytes'] = $info_png_chunk_type_text['sample_depth_bits'] / 8;
338
339 $s_plt_offset = 1;
340 $paletteCounter = 0;
341 while ($s_plt_offset < strlen($otherdata)) {
342
343 $info_png_chunk_type_text['red'][$paletteCounter] = getid3_lib::BigEndian2Int(substr($otherdata, $s_plt_offset, $info_png_chunk_type_text['sample_depth_bytes']));
344 $s_plt_offset += $info_png_chunk_type_text['sample_depth_bytes'];
345
346 $info_png_chunk_type_text['green'][$paletteCounter] = getid3_lib::BigEndian2Int(substr($otherdata, $s_plt_offset, $info_png_chunk_type_text['sample_depth_bytes']));
347 $s_plt_offset += $info_png_chunk_type_text['sample_depth_bytes'];
348
349 $info_png_chunk_type_text['blue'][$paletteCounter] = getid3_lib::BigEndian2Int(substr($otherdata, $s_plt_offset, $info_png_chunk_type_text['sample_depth_bytes']));
350 $s_plt_offset += $info_png_chunk_type_text['sample_depth_bytes'];
351
352 $info_png_chunk_type_text['alpha'][$paletteCounter] = getid3_lib::BigEndian2Int(substr($otherdata, $s_plt_offset, $info_png_chunk_type_text['sample_depth_bytes']));
353 $s_plt_offset += $info_png_chunk_type_text['sample_depth_bytes'];
354
355 $info_png_chunk_type_text['frequency'][$paletteCounter] = getid3_lib::BigEndian2Int(substr($otherdata, $s_plt_offset, 2));
356 $s_plt_offset += 2;
357
358 $paletteCounter++;
359 }
360 break;
361
362
363 case 'hIST': // Palette Histogram
364 $info_png_chunk_type_text['header'] = $chunk;
365 $h_ist_counter = 0;
366 while ($h_ist_counter < strlen($chunk['data'])) {
367 $info_png_chunk_type_text[$h_ist_counter] = getid3_lib::BigEndian2Int(substr($chunk['data'], $h_ist_counter / 2, 2));
368 $h_ist_counter += 2;
369 }
370 break;
371
372
373 case 'tIME': // Image Last-Modification Time
374 $info_png_chunk_type_text['header'] = $chunk;
375 $info_png_chunk_type_text['year'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 2));
376 $info_png_chunk_type_text['month'] = getid3_lib::BigEndian2Int($chunk['data']{2});
377 $info_png_chunk_type_text['day'] = getid3_lib::BigEndian2Int($chunk['data']{3});
378 $info_png_chunk_type_text['hour'] = getid3_lib::BigEndian2Int($chunk['data']{4});
379 $info_png_chunk_type_text['minute'] = getid3_lib::BigEndian2Int($chunk['data']{5});
380 $info_png_chunk_type_text['second'] = getid3_lib::BigEndian2Int($chunk['data']{6});
381 $info_png_chunk_type_text['unix'] = gmmktime($info_png_chunk_type_text['hour'], $info_png_chunk_type_text['minute'], $info_png_chunk_type_text['second'], $info_png_chunk_type_text['month'], $info_png_chunk_type_text['day'], $info_png_chunk_type_text['year']);
382 break;
383
384
385 case 'oFFs': // Image Offset
386 $info_png_chunk_type_text['header'] = $chunk;
387 $info_png_chunk_type_text['position_x'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 4), false, true);
388 $info_png_chunk_type_text['position_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 4, 4), false, true);
389 $info_png_chunk_type_text['unit_specifier'] = getid3_lib::BigEndian2Int($chunk['data'][8]);
390 $info_png_chunk_type_text['unit'] = getid3_png::PNGoFFsUnitLookup($info_png_chunk_type_text['unit_specifier']);
391 break;
392
393
394 case 'pCAL': // Calibration Of Pixel Values
395 $info_png_chunk_type_text['header'] = $chunk;
396 list($calibrationname, $otherdata) = explode("\x00", $chunk['data'], 2);
397 $info_png_chunk_type_text['calibration_name'] = $calibrationname;
398 $info_png_chunk_type_text['original_zero'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 4), false, true);
399 $info_png_chunk_type_text['original_max'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 4, 4), false, true);
400 $info_png_chunk_type_text['equation_type'] = getid3_lib::BigEndian2Int($chunk['data'][8]);
401 $info_png_chunk_type_text['equation_type_text'] = getid3_png::PNGpCALequationTypeLookup($info_png_chunk_type_text['equation_type']);
402 $info_png_chunk_type_text['parameter_count'] = getid3_lib::BigEndian2Int($chunk['data'][9]);
403 $info_png_chunk_type_text['parameters'] = explode("\x00", substr($chunk['data'], 10));
404 break;
405
406
407 case 'sCAL': // Physical Scale Of Image Subject
408 $info_png_chunk_type_text['header'] = $chunk;
409 $info_png_chunk_type_text['unit_specifier'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 1));
410 $info_png_chunk_type_text['unit'] = getid3_png::PNGsCALUnitLookup($info_png_chunk_type_text['unit_specifier']);
411 list($info_png_chunk_type_text['pixel_width'], $info_png_chunk_type_text['pixel_height']) = explode("\x00", substr($chunk['data'], 1));
412 break;
413
414
415 case 'gIFg': // GIF Graphic Control Extension
416 $gIFg_counter = 0;
417 if (isset($info_png_chunk_type_text) && is_array($info_png_chunk_type_text)) {
418 $gIFg_counter = count($info_png_chunk_type_text);
419 }
420 $info_png_chunk_type_text[$gIFg_counter]['header'] = $chunk;
421 $info_png_chunk_type_text[$gIFg_counter]['disposal_method'] = getid3_lib::BigEndian2Int($chunk['data'][0]);
422 $info_png_chunk_type_text[$gIFg_counter]['user_input_flag'] = getid3_lib::BigEndian2Int($chunk['data'][1]);
423 $info_png_chunk_type_text[$gIFg_counter]['delay_time'] = getid3_lib::BigEndian2Int($chunk['data'][2]);
424 break;
425
426
427 case 'gIFx': // GIF Application Extension
428 $gIFx_counter = 0;
429 if (isset($info_png_chunk_type_text) && is_array($info_png_chunk_type_text)) {
430 $gIFx_counter = count($info_png_chunk_type_text);
431 }
432 $info_png_chunk_type_text[$gIFx_counter]['header'] = $chunk;
433 $info_png_chunk_type_text[$gIFx_counter]['application_identifier'] = substr($chunk['data'], 0, 8);
434 $info_png_chunk_type_text[$gIFx_counter]['authentication_code'] = substr($chunk['data'], 8, 3);
435 $info_png_chunk_type_text[$gIFx_counter]['application_data'] = substr($chunk['data'], 11);
436 break;
437
438
439 case 'IDAT': // Image Data
440 $idat_information_field_index = 0;
441 if (isset($info_png['IDAT']) && is_array($info_png['IDAT'])) {
442 $idat_information_field_index = count($info_png['IDAT']);
443 }
444 unset($chunk['data']);
445 $info_png_chunk_type_text[$idat_information_field_index]['header'] = $chunk;
446 break;
447
448
449 case 'IEND': // Image Trailer
450 $info_png_chunk_type_text['header'] = $chunk;
451 break;
452
453
454 default:
455 $info_png_chunk_type_text['header'] = $chunk;
456 $getid3->warning('Unhandled chunk type: '.$chunk['type_text']);
457 break;
458 }
459 }
460
461 return true;
462 }
463
464
465
466 public static function PNGsRGBintentLookup($sRGB) {
467
468 static $lookup = array (
469 0 => 'Perceptual',
470 1 => 'Relative colorimetric',
471 2 => 'Saturation',
472 3 => 'Absolute colorimetric'
473 );
474 return (isset($lookup[$sRGB]) ? $lookup[$sRGB] : 'invalid');
475 }
476
477
478
479 public static function PNGcompressionMethodLookup($compression_method) {
480
481 return ($compression_method == 0 ? 'deflate/inflate' : 'invalid');
482 }
483
484
485
486 public static function PNGpHYsUnitLookup($unit_id) {
487
488 static $lookup = array (
489 0 => 'unknown',
490 1 => 'meter'
491 );
492 return (isset($lookup[$unit_id]) ? $lookup[$unit_id] : 'invalid');
493 }
494
495
496
497 public static function PNGoFFsUnitLookup($unit_id) {
498
499 static $lookup = array (
500 0 => 'pixel',
501 1 => 'micrometer'
502 );
503 return (isset($lookup[$unit_id]) ? $lookup[$unit_id] : 'invalid');
504 }
505
506
507
508 public static function PNGpCALequationTypeLookup($equation_type) {
509
510 static $lookup = array (
511 0 => 'Linear mapping',
512 1 => 'Base-e exponential mapping',
513 2 => 'Arbitrary-base exponential mapping',
514 3 => 'Hyperbolic mapping'
515 );
516 return (isset($lookup[$equation_type]) ? $lookup[$equation_type] : 'invalid');
517 }
518
519
520
521 public static function PNGsCALUnitLookup($unit_id) {
522
523 static $lookup = array (
524 0 => 'meter',
525 1 => 'radian'
526 );
527 return (isset($lookup[$unit_id]) ? $lookup[$unit_id] : 'invalid');
528 }
529
530
531
532 public static function IHDRcalculateBitsPerSample($color_type, $bit_depth) {
533
534 switch ($color_type) {
535 case 0: // Each pixel is a grayscale sample.
536 return $bit_depth;
537
538 case 2: // Each pixel is an R,G,B triple
539 return 3 * $bit_depth;
540
541 case 3: // Each pixel is a palette index; a PLTE chunk must appear.
542 return $bit_depth;
543
544 case 4: // Each pixel is a grayscale sample, followed by an alpha sample.
545 return 2 * $bit_depth;
546
547 case 6: // Each pixel is an R,G,B triple, followed by an alpha sample.
548 return 4 * $bit_depth;
549 }
550 return false;
551 }
552
553 }
554
555
556 ?>