ILIAS  release_5-2 Revision v5.2.25-18-g3f80b828510
Png.php
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1<?php
2
3namespace GetId3\Module\Graphic;
4
5use GetId3\Handler\BaseHandler;
6use GetId3\Lib\Helper;
7
10// available at http://getid3.sourceforge.net //
11// or http://www.getid3.org //
13// See readme.txt for more details //
15// //
16// module.graphic.png.php //
17// module for analyzing PNG Image files //
18// dependencies: NONE //
19// ///
21
29class Png extends BaseHandler
30{
31
36 public function analyze()
37 {
38 $info = &$this->getid3->info;
39
40 // shortcut
41 $info['png'] = array();
42 $thisfile_png = &$info['png'];
43
44 $info['fileformat'] = 'png';
45 $info['video']['dataformat'] = 'png';
46 $info['video']['lossless'] = false;
47
48 fseek($this->getid3->fp, $info['avdataoffset'], SEEK_SET);
49 $PNGfiledata = fread($this->getid3->fp, $this->getid3->fread_buffer_size());
50 $offset = 0;
51
52 $PNGidentifier = substr($PNGfiledata, $offset, 8); // $89 $50 $4E $47 $0D $0A $1A $0A
53 $offset += 8;
54
55 if ($PNGidentifier != "\x89\x50\x4E\x47\x0D\x0A\x1A\x0A") {
56 $info['error'][] = 'First 8 bytes of file ('.Helper::PrintHexBytes($PNGidentifier).') did not match expected PNG identifier';
57 unset($info['fileformat']);
58
59 return false;
60 }
61
62 while (((ftell($this->getid3->fp) - (strlen($PNGfiledata) - $offset)) < $info['filesize'])) {
63 $chunk['data_length'] = Helper::BigEndian2Int(substr($PNGfiledata, $offset, 4));
64 $offset += 4;
65 while (((strlen($PNGfiledata) - $offset) < ($chunk['data_length'] + 4)) && (ftell($this->getid3->fp) < $info['filesize'])) {
66 $PNGfiledata .= fread($this->getid3->fp, $this->getid3->fread_buffer_size());
67 }
68 $chunk['type_text'] = substr($PNGfiledata, $offset, 4);
69 $offset += 4;
70 $chunk['type_raw'] = Helper::BigEndian2Int($chunk['type_text']);
71 $chunk['data'] = substr($PNGfiledata, $offset, $chunk['data_length']);
72 $offset += $chunk['data_length'];
73 $chunk['crc'] = Helper::BigEndian2Int(substr($PNGfiledata, $offset, 4));
74 $offset += 4;
75
76 $chunk['flags']['ancilliary'] = (bool) ($chunk['type_raw'] & 0x20000000);
77 $chunk['flags']['private'] = (bool) ($chunk['type_raw'] & 0x00200000);
78 $chunk['flags']['reserved'] = (bool) ($chunk['type_raw'] & 0x00002000);
79 $chunk['flags']['safe_to_copy'] = (bool) ($chunk['type_raw'] & 0x00000020);
80
81 // shortcut
82 $thisfile_png[$chunk['type_text']] = array();
83 $thisfile_png_chunk_type_text = &$thisfile_png[$chunk['type_text']];
84
85 switch ($chunk['type_text']) {
86
87 case 'IHDR': // Image Header
88 $thisfile_png_chunk_type_text['header'] = $chunk;
89 $thisfile_png_chunk_type_text['width'] = Helper::BigEndian2Int(substr($chunk['data'], 0, 4));
90 $thisfile_png_chunk_type_text['height'] = Helper::BigEndian2Int(substr($chunk['data'], 4, 4));
91 $thisfile_png_chunk_type_text['raw']['bit_depth'] = Helper::BigEndian2Int(substr($chunk['data'], 8, 1));
92 $thisfile_png_chunk_type_text['raw']['color_type'] = Helper::BigEndian2Int(substr($chunk['data'], 9, 1));
93 $thisfile_png_chunk_type_text['raw']['compression_method'] = Helper::BigEndian2Int(substr($chunk['data'], 10, 1));
94 $thisfile_png_chunk_type_text['raw']['filter_method'] = Helper::BigEndian2Int(substr($chunk['data'], 11, 1));
95 $thisfile_png_chunk_type_text['raw']['interlace_method'] = Helper::BigEndian2Int(substr($chunk['data'], 12, 1));
96
97 $thisfile_png_chunk_type_text['compression_method_text'] = $this->PNGcompressionMethodLookup($thisfile_png_chunk_type_text['raw']['compression_method']);
98 $thisfile_png_chunk_type_text['color_type']['palette'] = (bool) ($thisfile_png_chunk_type_text['raw']['color_type'] & 0x01);
99 $thisfile_png_chunk_type_text['color_type']['true_color'] = (bool) ($thisfile_png_chunk_type_text['raw']['color_type'] & 0x02);
100 $thisfile_png_chunk_type_text['color_type']['alpha'] = (bool) ($thisfile_png_chunk_type_text['raw']['color_type'] & 0x04);
101
102 $info['video']['resolution_x'] = $thisfile_png_chunk_type_text['width'];
103 $info['video']['resolution_y'] = $thisfile_png_chunk_type_text['height'];
104
105 $info['video']['bits_per_sample'] = $this->IHDRcalculateBitsPerSample($thisfile_png_chunk_type_text['raw']['color_type'], $thisfile_png_chunk_type_text['raw']['bit_depth']);
106 break;
107
108 case 'PLTE': // Palette
109 $thisfile_png_chunk_type_text['header'] = $chunk;
110 $paletteoffset = 0;
111 for ($i = 0; $i <= 255; $i++) {
112 //$thisfile_png_chunk_type_text['red'][$i] = GetId3_lib::BigEndian2Int(substr($chunk['data'], $paletteoffset++, 1));
113 //$thisfile_png_chunk_type_text['green'][$i] = GetId3_lib::BigEndian2Int(substr($chunk['data'], $paletteoffset++, 1));
114 //$thisfile_png_chunk_type_text['blue'][$i] = GetId3_lib::BigEndian2Int(substr($chunk['data'], $paletteoffset++, 1));
115 $red = Helper::BigEndian2Int(substr($chunk['data'], $paletteoffset++, 1));
116 $green = Helper::BigEndian2Int(substr($chunk['data'], $paletteoffset++, 1));
117 $blue = Helper::BigEndian2Int(substr($chunk['data'], $paletteoffset++, 1));
118 $thisfile_png_chunk_type_text[$i] = (($red << 16) | ($green << 8) | ($blue));
119 }
120 break;
121
122 case 'tRNS': // Transparency
123 $thisfile_png_chunk_type_text['header'] = $chunk;
124 switch ($thisfile_png['IHDR']['raw']['color_type']) {
125 case 0:
126 $thisfile_png_chunk_type_text['transparent_color_gray'] = Helper::BigEndian2Int(substr($chunk['data'], 0, 2));
127 break;
128
129 case 2:
130 $thisfile_png_chunk_type_text['transparent_color_red'] = Helper::BigEndian2Int(substr($chunk['data'], 0, 2));
131 $thisfile_png_chunk_type_text['transparent_color_green'] = Helper::BigEndian2Int(substr($chunk['data'], 2, 2));
132 $thisfile_png_chunk_type_text['transparent_color_blue'] = Helper::BigEndian2Int(substr($chunk['data'], 4, 2));
133 break;
134
135 case 3:
136 for ($i = 0; $i < strlen($chunk['data']); $i++) {
137 $thisfile_png_chunk_type_text['palette_opacity'][$i] = Helper::BigEndian2Int(substr($chunk['data'], $i, 1));
138 }
139 break;
140
141 case 4:
142 case 6:
143 $info['error'][] = 'Invalid color_type in tRNS chunk: '.$thisfile_png['IHDR']['raw']['color_type'];
144
145 default:
146 $info['warning'][] = 'Unhandled color_type in tRNS chunk: '.$thisfile_png['IHDR']['raw']['color_type'];
147 break;
148 }
149 break;
150
151 case 'gAMA': // Image Gamma
152 $thisfile_png_chunk_type_text['header'] = $chunk;
153 $thisfile_png_chunk_type_text['gamma'] = Helper::BigEndian2Int($chunk['data']) / 100000;
154 break;
155
156 case 'cHRM': // Primary Chromaticities
157 $thisfile_png_chunk_type_text['header'] = $chunk;
158 $thisfile_png_chunk_type_text['white_x'] = Helper::BigEndian2Int(substr($chunk['data'], 0, 4)) / 100000;
159 $thisfile_png_chunk_type_text['white_y'] = Helper::BigEndian2Int(substr($chunk['data'], 4, 4)) / 100000;
160 $thisfile_png_chunk_type_text['red_y'] = Helper::BigEndian2Int(substr($chunk['data'], 8, 4)) / 100000;
161 $thisfile_png_chunk_type_text['red_y'] = Helper::BigEndian2Int(substr($chunk['data'], 12, 4)) / 100000;
162 $thisfile_png_chunk_type_text['green_y'] = Helper::BigEndian2Int(substr($chunk['data'], 16, 4)) / 100000;
163 $thisfile_png_chunk_type_text['green_y'] = Helper::BigEndian2Int(substr($chunk['data'], 20, 4)) / 100000;
164 $thisfile_png_chunk_type_text['blue_y'] = Helper::BigEndian2Int(substr($chunk['data'], 24, 4)) / 100000;
165 $thisfile_png_chunk_type_text['blue_y'] = Helper::BigEndian2Int(substr($chunk['data'], 28, 4)) / 100000;
166 break;
167
168 case 'sRGB': // Standard RGB Color Space
169 $thisfile_png_chunk_type_text['header'] = $chunk;
170 $thisfile_png_chunk_type_text['reindering_intent'] = Helper::BigEndian2Int($chunk['data']);
171 $thisfile_png_chunk_type_text['reindering_intent_text'] = $this->PNGsRGBintentLookup($thisfile_png_chunk_type_text['reindering_intent']);
172 break;
173
174 case 'iCCP': // Embedded ICC Profile
175 $thisfile_png_chunk_type_text['header'] = $chunk;
176 list($profilename, $compressiondata) = explode("\x00", $chunk['data'], 2);
177 $thisfile_png_chunk_type_text['profile_name'] = $profilename;
178 $thisfile_png_chunk_type_text['compression_method'] = Helper::BigEndian2Int(substr($compressiondata, 0, 1));
179 $thisfile_png_chunk_type_text['compression_profile'] = substr($compressiondata, 1);
180
181 $thisfile_png_chunk_type_text['compression_method_text'] = $this->PNGcompressionMethodLookup($thisfile_png_chunk_type_text['compression_method']);
182 break;
183
184 case 'tEXt': // Textual Data
185 $thisfile_png_chunk_type_text['header'] = $chunk;
186 list($keyword, $text) = explode("\x00", $chunk['data'], 2);
187 $thisfile_png_chunk_type_text['keyword'] = $keyword;
188 $thisfile_png_chunk_type_text['text'] = $text;
189
190 $thisfile_png['comments'][$thisfile_png_chunk_type_text['keyword']][] = $thisfile_png_chunk_type_text['text'];
191 break;
192
193 case 'zTXt': // Compressed Textual Data
194 $thisfile_png_chunk_type_text['header'] = $chunk;
195 list($keyword, $otherdata) = explode("\x00", $chunk['data'], 2);
196 $thisfile_png_chunk_type_text['keyword'] = $keyword;
197 $thisfile_png_chunk_type_text['compression_method'] = Helper::BigEndian2Int(substr($otherdata, 0, 1));
198 $thisfile_png_chunk_type_text['compressed_text'] = substr($otherdata, 1);
199 $thisfile_png_chunk_type_text['compression_method_text'] = $this->PNGcompressionMethodLookup($thisfile_png_chunk_type_text['compression_method']);
200 switch ($thisfile_png_chunk_type_text['compression_method']) {
201 case 0:
202 $thisfile_png_chunk_type_text['text'] = gzuncompress($thisfile_png_chunk_type_text['compressed_text']);
203 break;
204
205 default:
206 // unknown compression method
207 break;
208 }
209
210 if (isset($thisfile_png_chunk_type_text['text'])) {
211 $thisfile_png['comments'][$thisfile_png_chunk_type_text['keyword']][] = $thisfile_png_chunk_type_text['text'];
212 }
213 break;
214
215 case 'iTXt': // International Textual Data
216 $thisfile_png_chunk_type_text['header'] = $chunk;
217 list($keyword, $otherdata) = explode("\x00", $chunk['data'], 2);
218 $thisfile_png_chunk_type_text['keyword'] = $keyword;
219 $thisfile_png_chunk_type_text['compression'] = (bool) Helper::BigEndian2Int(substr($otherdata, 0, 1));
220 $thisfile_png_chunk_type_text['compression_method'] = Helper::BigEndian2Int(substr($otherdata, 1, 1));
221 $thisfile_png_chunk_type_text['compression_method_text'] = $this->PNGcompressionMethodLookup($thisfile_png_chunk_type_text['compression_method']);
222 list($languagetag, $translatedkeyword, $text) = explode("\x00", substr($otherdata, 2), 3);
223 $thisfile_png_chunk_type_text['language_tag'] = $languagetag;
224 $thisfile_png_chunk_type_text['translated_keyword'] = $translatedkeyword;
225
226 if ($thisfile_png_chunk_type_text['compression']) {
227
228 switch ($thisfile_png_chunk_type_text['compression_method']) {
229 case 0:
230 $thisfile_png_chunk_type_text['text'] = gzuncompress($text);
231 break;
232
233 default:
234 // unknown compression method
235 break;
236 }
237
238 } else {
239
240 $thisfile_png_chunk_type_text['text'] = $text;
241
242 }
243
244 if (isset($thisfile_png_chunk_type_text['text'])) {
245 $thisfile_png['comments'][$thisfile_png_chunk_type_text['keyword']][] = $thisfile_png_chunk_type_text['text'];
246 }
247 break;
248
249 case 'bKGD': // Background Color
250 $thisfile_png_chunk_type_text['header'] = $chunk;
251 switch ($thisfile_png['IHDR']['raw']['color_type']) {
252 case 0:
253 case 4:
254 $thisfile_png_chunk_type_text['background_gray'] = Helper::BigEndian2Int($chunk['data']);
255 break;
256
257 case 2:
258 case 6:
259 $thisfile_png_chunk_type_text['background_red'] = Helper::BigEndian2Int(substr($chunk['data'], 0 * $thisfile_png['IHDR']['raw']['bit_depth'], $thisfile_png['IHDR']['raw']['bit_depth']));
260 $thisfile_png_chunk_type_text['background_green'] = Helper::BigEndian2Int(substr($chunk['data'], 1 * $thisfile_png['IHDR']['raw']['bit_depth'], $thisfile_png['IHDR']['raw']['bit_depth']));
261 $thisfile_png_chunk_type_text['background_blue'] = Helper::BigEndian2Int(substr($chunk['data'], 2 * $thisfile_png['IHDR']['raw']['bit_depth'], $thisfile_png['IHDR']['raw']['bit_depth']));
262 break;
263
264 case 3:
265 $thisfile_png_chunk_type_text['background_index'] = Helper::BigEndian2Int($chunk['data']);
266 break;
267
268 default:
269 break;
270 }
271 break;
272
273 case 'pHYs': // Physical Pixel Dimensions
274 $thisfile_png_chunk_type_text['header'] = $chunk;
275 $thisfile_png_chunk_type_text['pixels_per_unit_x'] = Helper::BigEndian2Int(substr($chunk['data'], 0, 4));
276 $thisfile_png_chunk_type_text['pixels_per_unit_y'] = Helper::BigEndian2Int(substr($chunk['data'], 4, 4));
277 $thisfile_png_chunk_type_text['unit_specifier'] = Helper::BigEndian2Int(substr($chunk['data'], 8, 1));
278 $thisfile_png_chunk_type_text['unit'] = $this->PNGpHYsUnitLookup($thisfile_png_chunk_type_text['unit_specifier']);
279 break;
280
281 case 'sBIT': // Significant Bits
282 $thisfile_png_chunk_type_text['header'] = $chunk;
283 switch ($thisfile_png['IHDR']['raw']['color_type']) {
284 case 0:
285 $thisfile_png_chunk_type_text['significant_bits_gray'] = Helper::BigEndian2Int(substr($chunk['data'], 0, 1));
286 break;
287
288 case 2:
289 case 3:
290 $thisfile_png_chunk_type_text['significant_bits_red'] = Helper::BigEndian2Int(substr($chunk['data'], 0, 1));
291 $thisfile_png_chunk_type_text['significant_bits_green'] = Helper::BigEndian2Int(substr($chunk['data'], 1, 1));
292 $thisfile_png_chunk_type_text['significant_bits_blue'] = Helper::BigEndian2Int(substr($chunk['data'], 2, 1));
293 break;
294
295 case 4:
296 $thisfile_png_chunk_type_text['significant_bits_gray'] = Helper::BigEndian2Int(substr($chunk['data'], 0, 1));
297 $thisfile_png_chunk_type_text['significant_bits_alpha'] = Helper::BigEndian2Int(substr($chunk['data'], 1, 1));
298 break;
299
300 case 6:
301 $thisfile_png_chunk_type_text['significant_bits_red'] = Helper::BigEndian2Int(substr($chunk['data'], 0, 1));
302 $thisfile_png_chunk_type_text['significant_bits_green'] = Helper::BigEndian2Int(substr($chunk['data'], 1, 1));
303 $thisfile_png_chunk_type_text['significant_bits_blue'] = Helper::BigEndian2Int(substr($chunk['data'], 2, 1));
304 $thisfile_png_chunk_type_text['significant_bits_alpha'] = Helper::BigEndian2Int(substr($chunk['data'], 3, 1));
305 break;
306
307 default:
308 break;
309 }
310 break;
311
312 case 'sPLT': // Suggested Palette
313 $thisfile_png_chunk_type_text['header'] = $chunk;
314 list($palettename, $otherdata) = explode("\x00", $chunk['data'], 2);
315 $thisfile_png_chunk_type_text['palette_name'] = $palettename;
316 $sPLToffset = 0;
317 $thisfile_png_chunk_type_text['sample_depth_bits'] = Helper::BigEndian2Int(substr($otherdata, $sPLToffset, 1));
318 $sPLToffset += 1;
319 $thisfile_png_chunk_type_text['sample_depth_bytes'] = $thisfile_png_chunk_type_text['sample_depth_bits'] / 8;
320 $paletteCounter = 0;
321 while ($sPLToffset < strlen($otherdata)) {
322 $thisfile_png_chunk_type_text['red'][$paletteCounter] = Helper::BigEndian2Int(substr($otherdata, $sPLToffset, $thisfile_png_chunk_type_text['sample_depth_bytes']));
323 $sPLToffset += $thisfile_png_chunk_type_text['sample_depth_bytes'];
324 $thisfile_png_chunk_type_text['green'][$paletteCounter] = Helper::BigEndian2Int(substr($otherdata, $sPLToffset, $thisfile_png_chunk_type_text['sample_depth_bytes']));
325 $sPLToffset += $thisfile_png_chunk_type_text['sample_depth_bytes'];
326 $thisfile_png_chunk_type_text['blue'][$paletteCounter] = Helper::BigEndian2Int(substr($otherdata, $sPLToffset, $thisfile_png_chunk_type_text['sample_depth_bytes']));
327 $sPLToffset += $thisfile_png_chunk_type_text['sample_depth_bytes'];
328 $thisfile_png_chunk_type_text['alpha'][$paletteCounter] = Helper::BigEndian2Int(substr($otherdata, $sPLToffset, $thisfile_png_chunk_type_text['sample_depth_bytes']));
329 $sPLToffset += $thisfile_png_chunk_type_text['sample_depth_bytes'];
330 $thisfile_png_chunk_type_text['frequency'][$paletteCounter] = Helper::BigEndian2Int(substr($otherdata, $sPLToffset, 2));
331 $sPLToffset += 2;
332 $paletteCounter++;
333 }
334 break;
335
336 case 'hIST': // Palette Histogram
337 $thisfile_png_chunk_type_text['header'] = $chunk;
338 $hISTcounter = 0;
339 while ($hISTcounter < strlen($chunk['data'])) {
340 $thisfile_png_chunk_type_text[$hISTcounter] = Helper::BigEndian2Int(substr($chunk['data'], $hISTcounter / 2, 2));
341 $hISTcounter += 2;
342 }
343 break;
344
345 case 'tIME': // Image Last-Modification Time
346 $thisfile_png_chunk_type_text['header'] = $chunk;
347 $thisfile_png_chunk_type_text['year'] = Helper::BigEndian2Int(substr($chunk['data'], 0, 2));
348 $thisfile_png_chunk_type_text['month'] = Helper::BigEndian2Int(substr($chunk['data'], 2, 1));
349 $thisfile_png_chunk_type_text['day'] = Helper::BigEndian2Int(substr($chunk['data'], 3, 1));
350 $thisfile_png_chunk_type_text['hour'] = Helper::BigEndian2Int(substr($chunk['data'], 4, 1));
351 $thisfile_png_chunk_type_text['minute'] = Helper::BigEndian2Int(substr($chunk['data'], 5, 1));
352 $thisfile_png_chunk_type_text['second'] = Helper::BigEndian2Int(substr($chunk['data'], 6, 1));
353 $thisfile_png_chunk_type_text['unix'] = gmmktime($thisfile_png_chunk_type_text['hour'], $thisfile_png_chunk_type_text['minute'], $thisfile_png_chunk_type_text['second'], $thisfile_png_chunk_type_text['month'], $thisfile_png_chunk_type_text['day'], $thisfile_png_chunk_type_text['year']);
354 break;
355
356 case 'oFFs': // Image Offset
357 $thisfile_png_chunk_type_text['header'] = $chunk;
358 $thisfile_png_chunk_type_text['position_x'] = Helper::BigEndian2Int(substr($chunk['data'], 0, 4), false, true);
359 $thisfile_png_chunk_type_text['position_y'] = Helper::BigEndian2Int(substr($chunk['data'], 4, 4), false, true);
360 $thisfile_png_chunk_type_text['unit_specifier'] = Helper::BigEndian2Int(substr($chunk['data'], 8, 1));
361 $thisfile_png_chunk_type_text['unit'] = $this->PNGoFFsUnitLookup($thisfile_png_chunk_type_text['unit_specifier']);
362 break;
363
364 case 'pCAL': // Calibration Of Pixel Values
365 $thisfile_png_chunk_type_text['header'] = $chunk;
366 list($calibrationname, $otherdata) = explode("\x00", $chunk['data'], 2);
367 $thisfile_png_chunk_type_text['calibration_name'] = $calibrationname;
368 $pCALoffset = 0;
369 $thisfile_png_chunk_type_text['original_zero'] = Helper::BigEndian2Int(substr($chunk['data'], $pCALoffset, 4), false, true);
370 $pCALoffset += 4;
371 $thisfile_png_chunk_type_text['original_max'] = Helper::BigEndian2Int(substr($chunk['data'], $pCALoffset, 4), false, true);
372 $pCALoffset += 4;
373 $thisfile_png_chunk_type_text['equation_type'] = Helper::BigEndian2Int(substr($chunk['data'], $pCALoffset, 1));
374 $pCALoffset += 1;
375 $thisfile_png_chunk_type_text['equation_type_text'] = $this->PNGpCALequationTypeLookup($thisfile_png_chunk_type_text['equation_type']);
376 $thisfile_png_chunk_type_text['parameter_count'] = Helper::BigEndian2Int(substr($chunk['data'], $pCALoffset, 1));
377 $pCALoffset += 1;
378 $thisfile_png_chunk_type_text['parameters'] = explode("\x00", substr($chunk['data'], $pCALoffset));
379 break;
380
381 case 'sCAL': // Physical Scale Of Image Subject
382 $thisfile_png_chunk_type_text['header'] = $chunk;
383 $thisfile_png_chunk_type_text['unit_specifier'] = Helper::BigEndian2Int(substr($chunk['data'], 0, 1));
384 $thisfile_png_chunk_type_text['unit'] = $this->PNGsCALUnitLookup($thisfile_png_chunk_type_text['unit_specifier']);
385 list($pixelwidth, $pixelheight) = explode("\x00", substr($chunk['data'], 1));
386 $thisfile_png_chunk_type_text['pixel_width'] = $pixelwidth;
387 $thisfile_png_chunk_type_text['pixel_height'] = $pixelheight;
388 break;
389
390 case 'gIFg': // GIF Graphic Control Extension
391 $gIFgCounter = 0;
392 if (isset($thisfile_png_chunk_type_text) && is_array($thisfile_png_chunk_type_text)) {
393 $gIFgCounter = count($thisfile_png_chunk_type_text);
394 }
395 $thisfile_png_chunk_type_text[$gIFgCounter]['header'] = $chunk;
396 $thisfile_png_chunk_type_text[$gIFgCounter]['disposal_method'] = Helper::BigEndian2Int(substr($chunk['data'], 0, 1));
397 $thisfile_png_chunk_type_text[$gIFgCounter]['user_input_flag'] = Helper::BigEndian2Int(substr($chunk['data'], 1, 1));
398 $thisfile_png_chunk_type_text[$gIFgCounter]['delay_time'] = Helper::BigEndian2Int(substr($chunk['data'], 2, 2));
399 break;
400
401 case 'gIFx': // GIF Application Extension
402 $gIFxCounter = 0;
403 if (isset($thisfile_png_chunk_type_text) && is_array($thisfile_png_chunk_type_text)) {
404 $gIFxCounter = count($thisfile_png_chunk_type_text);
405 }
406 $thisfile_png_chunk_type_text[$gIFxCounter]['header'] = $chunk;
407 $thisfile_png_chunk_type_text[$gIFxCounter]['application_identifier'] = substr($chunk['data'], 0, 8);
408 $thisfile_png_chunk_type_text[$gIFxCounter]['authentication_code'] = substr($chunk['data'], 8, 3);
409 $thisfile_png_chunk_type_text[$gIFxCounter]['application_data'] = substr($chunk['data'], 11);
410 break;
411
412 case 'IDAT': // Image Data
413 $idatinformationfieldindex = 0;
414 if (isset($thisfile_png['IDAT']) && is_array($thisfile_png['IDAT'])) {
415 $idatinformationfieldindex = count($thisfile_png['IDAT']);
416 }
417 unset($chunk['data']);
418 $thisfile_png_chunk_type_text[$idatinformationfieldindex]['header'] = $chunk;
419 break;
420
421 case 'IEND': // Image Trailer
422 $thisfile_png_chunk_type_text['header'] = $chunk;
423 break;
424
425 default:
426 //unset($chunk['data']);
427 $thisfile_png_chunk_type_text['header'] = $chunk;
428 $info['warning'][] = 'Unhandled chunk type: '.$chunk['type_text'];
429 break;
430 }
431 }
432
433 return true;
434 }
435
442 public function PNGsRGBintentLookup($sRGB)
443 {
444 static $PNGsRGBintentLookup = array(
445 0 => 'Perceptual',
446 1 => 'Relative colorimetric',
447 2 => 'Saturation',
448 3 => 'Absolute colorimetric'
449 );
450
451 return (isset($PNGsRGBintentLookup[$sRGB]) ? $PNGsRGBintentLookup[$sRGB] : 'invalid');
452 }
453
460 public function PNGcompressionMethodLookup($compressionmethod)
461 {
462 static $PNGcompressionMethodLookup = array(
463 0 => 'deflate/inflate'
464 );
465
466 return (isset($PNGcompressionMethodLookup[$compressionmethod]) ? $PNGcompressionMethodLookup[$compressionmethod] : 'invalid');
467 }
468
475 public function PNGpHYsUnitLookup($unitid)
476 {
477 static $PNGpHYsUnitLookup = array(
478 0 => 'unknown',
479 1 => 'meter'
480 );
481
482 return (isset($PNGpHYsUnitLookup[$unitid]) ? $PNGpHYsUnitLookup[$unitid] : 'invalid');
483 }
484
491 public function PNGoFFsUnitLookup($unitid)
492 {
493 static $PNGoFFsUnitLookup = array(
494 0 => 'pixel',
495 1 => 'micrometer'
496 );
497
498 return (isset($PNGoFFsUnitLookup[$unitid]) ? $PNGoFFsUnitLookup[$unitid] : 'invalid');
499 }
500
507 public function PNGpCALequationTypeLookup($equationtype)
508 {
509 static $PNGpCALequationTypeLookup = array(
510 0 => 'Linear mapping',
511 1 => 'Base-e exponential mapping',
512 2 => 'Arbitrary-base exponential mapping',
513 3 => 'Hyperbolic mapping'
514 );
515
516 return (isset($PNGpCALequationTypeLookup[$equationtype]) ? $PNGpCALequationTypeLookup[$equationtype] : 'invalid');
517 }
518
525 public function PNGsCALUnitLookup($unitid)
526 {
527 static $PNGsCALUnitLookup = array(
528 0 => 'meter',
529 1 => 'radian'
530 );
531
532 return (isset($PNGsCALUnitLookup[$unitid]) ? $PNGsCALUnitLookup[$unitid] : 'invalid');
533 }
534
541 public function IHDRcalculateBitsPerSample($color_type, $bit_depth)
542 {
543 switch ($color_type) {
544 case 0: // Each pixel is a grayscale sample.
545
546 return $bit_depth;
547 break;
548
549 case 2: // Each pixel is an R,G,B triple
550
551 return 3 * $bit_depth;
552 break;
553
554 case 3: // Each pixel is a palette index; a PLTE chunk must appear.
555
556 return $bit_depth;
557 break;
558
559 case 4: // Each pixel is a grayscale sample, followed by an alpha sample.
560
561 return 2 * $bit_depth;
562 break;
563
564 case 6: // Each pixel is an R,G,B triple, followed by an alpha sample.
565
566 return 4 * $bit_depth;
567 break;
568 }
569
570 return false;
571 }
572
573}
php
An exception for terminatinating execution or to throw for unit testing.
GetId3\Handler\BaseHandler
GetId3() by James Heinrich info@getid3.org //.
Definition: BaseHandler.php:26
GetId3\Handler\BaseHandler\fseek
fseek($bytes, $whence=SEEK_SET)
Definition: BaseHandler.php:148
GetId3\Lib\Helper
GetId3() by James Heinrich info@getid3.org //.
Definition: Helper.php:27
GetId3\Lib\Helper\BigEndian2Int
static BigEndian2Int($byteword, $synchsafe=false, $signed=false)
Definition: Helper.php:374
GetId3\Module\Graphic\Png
GetId3() by James Heinrich info@getid3.org //.
Definition: Png.php:30
GetId3\Module\Graphic\Png\PNGsRGBintentLookup
PNGsRGBintentLookup($sRGB)
@staticvar array $PNGsRGBintentLookup
Definition: Png.php:442
GetId3\Module\Graphic\Png\IHDRcalculateBitsPerSample
IHDRcalculateBitsPerSample($color_type, $bit_depth)
Definition: Png.php:541
GetId3\Module\Graphic\Png\PNGpCALequationTypeLookup
PNGpCALequationTypeLookup($equationtype)
@staticvar array $PNGpCALequationTypeLookup
Definition: Png.php:507
GetId3\Module\Graphic\Png\PNGoFFsUnitLookup
PNGoFFsUnitLookup($unitid)
@staticvar array $PNGoFFsUnitLookup
Definition: Png.php:491
GetId3\Module\Graphic\Png\PNGpHYsUnitLookup
PNGpHYsUnitLookup($unitid)
@staticvar array $PNGpHYsUnitLookup
Definition: Png.php:475
GetId3\Module\Graphic\Png\PNGcompressionMethodLookup
PNGcompressionMethodLookup($compressionmethod)
@staticvar array $PNGcompressionMethodLookup
Definition: Png.php:460
GetId3\Module\Graphic\Png\PNGsCALUnitLookup
PNGsCALUnitLookup($unitid)
@staticvar array $PNGsCALUnitLookup
Definition: Png.php:525
$text
$text
Definition: example_020.php:127
$red
$red
Definition: example_030.php:80
$green
$green
Definition: example_030.php:83
$blue
$blue
Definition: example_030.php:81
$info
$info
Definition: example_052.php:80