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-rw-r--r--includes/getid3/module.graphic.png.php615
1 files changed, 615 insertions, 0 deletions
diff --git a/includes/getid3/module.graphic.png.php b/includes/getid3/module.graphic.png.php
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index 0000000..018062c
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+++ b/includes/getid3/module.graphic.png.php
@@ -0,0 +1,615 @@
+<?php
+
+/////////////////////////////////////////////////////////////////
+/// getID3() by James Heinrich <info@getid3.org> //
+// available at https://github.com/JamesHeinrich/getID3 //
+// or https://www.getid3.org //
+// or http://getid3.sourceforge.net //
+// see readme.txt for more details //
+/////////////////////////////////////////////////////////////////
+// //
+// module.graphic.png.php //
+// module for analyzing PNG Image files //
+// dependencies: NONE //
+// ///
+/////////////////////////////////////////////////////////////////
+
+if (!defined('GETID3_INCLUDEPATH')) { // prevent path-exposing attacks that access modules directly on public webservers
+ exit;
+}
+
+class getid3_png extends getid3_handler
+{
+ /**
+ * If data chunk is larger than this do not read it completely (getID3 only needs the first
+ * few dozen bytes for parsing).
+ *
+ * @var int
+ */
+ public $max_data_bytes = 10000000;
+
+ /**
+ * @return bool
+ */
+ public function Analyze() {
+
+ $info = &$this->getid3->info;
+
+ // shortcut
+ $info['png'] = array();
+ $thisfile_png = &$info['png'];
+
+ $info['fileformat'] = 'png';
+ $info['video']['dataformat'] = 'png';
+ $info['video']['lossless'] = false;
+
+ $this->fseek($info['avdataoffset']);
+ $PNGfiledata = $this->fread($this->getid3->fread_buffer_size());
+ $offset = 0;
+
+ $PNGidentifier = substr($PNGfiledata, $offset, 8); // $89 $50 $4E $47 $0D $0A $1A $0A
+ $offset += 8;
+
+ if ($PNGidentifier != "\x89\x50\x4E\x47\x0D\x0A\x1A\x0A") {
+ $this->error('First 8 bytes of file ('.getid3_lib::PrintHexBytes($PNGidentifier).') did not match expected PNG identifier');
+ unset($info['fileformat']);
+ return false;
+ }
+
+ while ((($this->ftell() - (strlen($PNGfiledata) - $offset)) < $info['filesize'])) {
+ $chunk['data_length'] = getid3_lib::BigEndian2Int(substr($PNGfiledata, $offset, 4));
+ if ($chunk['data_length'] === false) {
+ $this->error('Failed to read data_length at offset '.$offset);
+ return false;
+ }
+ $offset += 4;
+ $truncated_data = false;
+ while (((strlen($PNGfiledata) - $offset) < ($chunk['data_length'] + 4)) && ($this->ftell() < $info['filesize'])) {
+ if (strlen($PNGfiledata) < $this->max_data_bytes) {
+ $PNGfiledata .= $this->fread($this->getid3->fread_buffer_size());
+ } else {
+ $this->warning('At offset '.$offset.' chunk "'.substr($PNGfiledata, $offset, 4).'" exceeded max_data_bytes value of '.$this->max_data_bytes.', data chunk will be truncated at '.(strlen($PNGfiledata) - 8).' bytes');
+ break;
+ }
+ }
+ $chunk['type_text'] = substr($PNGfiledata, $offset, 4);
+ $offset += 4;
+ $chunk['type_raw'] = getid3_lib::BigEndian2Int($chunk['type_text']);
+ $chunk['data'] = substr($PNGfiledata, $offset, $chunk['data_length']);
+ $offset += $chunk['data_length'];
+ $chunk['crc'] = getid3_lib::BigEndian2Int(substr($PNGfiledata, $offset, 4));
+ $offset += 4;
+
+ $chunk['flags']['ancilliary'] = (bool) ($chunk['type_raw'] & 0x20000000);
+ $chunk['flags']['private'] = (bool) ($chunk['type_raw'] & 0x00200000);
+ $chunk['flags']['reserved'] = (bool) ($chunk['type_raw'] & 0x00002000);
+ $chunk['flags']['safe_to_copy'] = (bool) ($chunk['type_raw'] & 0x00000020);
+
+ // shortcut
+ $thisfile_png[$chunk['type_text']] = array();
+ $thisfile_png_chunk_type_text = &$thisfile_png[$chunk['type_text']];
+
+ switch ($chunk['type_text']) {
+
+ case 'IHDR': // Image Header
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ $thisfile_png_chunk_type_text['width'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 4));
+ $thisfile_png_chunk_type_text['height'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 4, 4));
+ $thisfile_png_chunk_type_text['raw']['bit_depth'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 8, 1));
+ $thisfile_png_chunk_type_text['raw']['color_type'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 9, 1));
+ $thisfile_png_chunk_type_text['raw']['compression_method'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 10, 1));
+ $thisfile_png_chunk_type_text['raw']['filter_method'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 11, 1));
+ $thisfile_png_chunk_type_text['raw']['interlace_method'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 12, 1));
+
+ $thisfile_png_chunk_type_text['compression_method_text'] = $this->PNGcompressionMethodLookup($thisfile_png_chunk_type_text['raw']['compression_method']);
+ $thisfile_png_chunk_type_text['color_type']['palette'] = (bool) ($thisfile_png_chunk_type_text['raw']['color_type'] & 0x01);
+ $thisfile_png_chunk_type_text['color_type']['true_color'] = (bool) ($thisfile_png_chunk_type_text['raw']['color_type'] & 0x02);
+ $thisfile_png_chunk_type_text['color_type']['alpha'] = (bool) ($thisfile_png_chunk_type_text['raw']['color_type'] & 0x04);
+
+ $info['video']['resolution_x'] = $thisfile_png_chunk_type_text['width'];
+ $info['video']['resolution_y'] = $thisfile_png_chunk_type_text['height'];
+
+ $info['video']['bits_per_sample'] = $this->IHDRcalculateBitsPerSample($thisfile_png_chunk_type_text['raw']['color_type'], $thisfile_png_chunk_type_text['raw']['bit_depth']);
+ break;
+
+
+ case 'PLTE': // Palette
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ $paletteoffset = 0;
+ for ($i = 0; $i <= 255; $i++) {
+ //$thisfile_png_chunk_type_text['red'][$i] = getid3_lib::BigEndian2Int(substr($chunk['data'], $paletteoffset++, 1));
+ //$thisfile_png_chunk_type_text['green'][$i] = getid3_lib::BigEndian2Int(substr($chunk['data'], $paletteoffset++, 1));
+ //$thisfile_png_chunk_type_text['blue'][$i] = getid3_lib::BigEndian2Int(substr($chunk['data'], $paletteoffset++, 1));
+ $red = getid3_lib::BigEndian2Int(substr($chunk['data'], $paletteoffset++, 1));
+ $green = getid3_lib::BigEndian2Int(substr($chunk['data'], $paletteoffset++, 1));
+ $blue = getid3_lib::BigEndian2Int(substr($chunk['data'], $paletteoffset++, 1));
+ $thisfile_png_chunk_type_text[$i] = (($red << 16) | ($green << 8) | ($blue));
+ }
+ break;
+
+
+ case 'tRNS': // Transparency
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ switch ($thisfile_png['IHDR']['raw']['color_type']) {
+ case 0:
+ $thisfile_png_chunk_type_text['transparent_color_gray'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 2));
+ break;
+
+ case 2:
+ $thisfile_png_chunk_type_text['transparent_color_red'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 2));
+ $thisfile_png_chunk_type_text['transparent_color_green'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 2, 2));
+ $thisfile_png_chunk_type_text['transparent_color_blue'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 4, 2));
+ break;
+
+ case 3:
+ for ($i = 0; $i < strlen($chunk['data']); $i++) {
+ $thisfile_png_chunk_type_text['palette_opacity'][$i] = getid3_lib::BigEndian2Int(substr($chunk['data'], $i, 1));
+ }
+ break;
+
+ case 4:
+ case 6:
+ $this->error('Invalid color_type in tRNS chunk: '.$thisfile_png['IHDR']['raw']['color_type']);
+ break;
+
+ default:
+ $this->warning('Unhandled color_type in tRNS chunk: '.$thisfile_png['IHDR']['raw']['color_type']);
+ break;
+ }
+ break;
+
+
+ case 'gAMA': // Image Gamma
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ $thisfile_png_chunk_type_text['gamma'] = getid3_lib::BigEndian2Int($chunk['data']) / 100000;
+ break;
+
+
+ case 'cHRM': // Primary Chromaticities
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ $thisfile_png_chunk_type_text['white_x'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 4)) / 100000;
+ $thisfile_png_chunk_type_text['white_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 4, 4)) / 100000;
+ $thisfile_png_chunk_type_text['red_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 8, 4)) / 100000;
+ $thisfile_png_chunk_type_text['red_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 12, 4)) / 100000;
+ $thisfile_png_chunk_type_text['green_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 16, 4)) / 100000;
+ $thisfile_png_chunk_type_text['green_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 20, 4)) / 100000;
+ $thisfile_png_chunk_type_text['blue_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 24, 4)) / 100000;
+ $thisfile_png_chunk_type_text['blue_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 28, 4)) / 100000;
+ break;
+
+
+ case 'sRGB': // Standard RGB Color Space
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ $thisfile_png_chunk_type_text['reindering_intent'] = getid3_lib::BigEndian2Int($chunk['data']);
+ $thisfile_png_chunk_type_text['reindering_intent_text'] = $this->PNGsRGBintentLookup($thisfile_png_chunk_type_text['reindering_intent']);
+ break;
+
+
+ case 'iCCP': // Embedded ICC Profile
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ list($profilename, $compressiondata) = explode("\x00", $chunk['data'], 2);
+ $thisfile_png_chunk_type_text['profile_name'] = $profilename;
+ $thisfile_png_chunk_type_text['compression_method'] = getid3_lib::BigEndian2Int(substr($compressiondata, 0, 1));
+ $thisfile_png_chunk_type_text['compression_profile'] = substr($compressiondata, 1);
+
+ $thisfile_png_chunk_type_text['compression_method_text'] = $this->PNGcompressionMethodLookup($thisfile_png_chunk_type_text['compression_method']);
+ break;
+
+
+ case 'tEXt': // Textual Data
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ list($keyword, $text) = explode("\x00", $chunk['data'], 2);
+ $thisfile_png_chunk_type_text['keyword'] = $keyword;
+ $thisfile_png_chunk_type_text['text'] = $text;
+
+ $thisfile_png['comments'][$thisfile_png_chunk_type_text['keyword']][] = $thisfile_png_chunk_type_text['text'];
+ break;
+
+
+ case 'zTXt': // Compressed Textual Data
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ list($keyword, $otherdata) = explode("\x00", $chunk['data'], 2);
+ $thisfile_png_chunk_type_text['keyword'] = $keyword;
+ $thisfile_png_chunk_type_text['compression_method'] = getid3_lib::BigEndian2Int(substr($otherdata, 0, 1));
+ $thisfile_png_chunk_type_text['compressed_text'] = substr($otherdata, 1);
+ $thisfile_png_chunk_type_text['compression_method_text'] = $this->PNGcompressionMethodLookup($thisfile_png_chunk_type_text['compression_method']);
+ switch ($thisfile_png_chunk_type_text['compression_method']) {
+ case 0:
+ $thisfile_png_chunk_type_text['text'] = gzuncompress($thisfile_png_chunk_type_text['compressed_text']);
+ break;
+
+ default:
+ // unknown compression method
+ break;
+ }
+
+ if (isset($thisfile_png_chunk_type_text['text'])) {
+ $thisfile_png['comments'][$thisfile_png_chunk_type_text['keyword']][] = $thisfile_png_chunk_type_text['text'];
+ }
+ break;
+
+
+ case 'iTXt': // International Textual Data
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ list($keyword, $otherdata) = explode("\x00", $chunk['data'], 2);
+ $thisfile_png_chunk_type_text['keyword'] = $keyword;
+ $thisfile_png_chunk_type_text['compression'] = (bool) getid3_lib::BigEndian2Int(substr($otherdata, 0, 1));
+ $thisfile_png_chunk_type_text['compression_method'] = getid3_lib::BigEndian2Int(substr($otherdata, 1, 1));
+ $thisfile_png_chunk_type_text['compression_method_text'] = $this->PNGcompressionMethodLookup($thisfile_png_chunk_type_text['compression_method']);
+ list($languagetag, $translatedkeyword, $text) = explode("\x00", substr($otherdata, 2), 3);
+ $thisfile_png_chunk_type_text['language_tag'] = $languagetag;
+ $thisfile_png_chunk_type_text['translated_keyword'] = $translatedkeyword;
+
+ if ($thisfile_png_chunk_type_text['compression']) {
+
+ switch ($thisfile_png_chunk_type_text['compression_method']) {
+ case 0:
+ $thisfile_png_chunk_type_text['text'] = gzuncompress($text);
+ break;
+
+ default:
+ // unknown compression method
+ break;
+ }
+
+ } else {
+
+ $thisfile_png_chunk_type_text['text'] = $text;
+
+ }
+
+ if (isset($thisfile_png_chunk_type_text['text'])) {
+ $thisfile_png['comments'][$thisfile_png_chunk_type_text['keyword']][] = $thisfile_png_chunk_type_text['text'];
+ }
+ break;
+
+
+ case 'bKGD': // Background Color
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ switch ($thisfile_png['IHDR']['raw']['color_type']) {
+ case 0:
+ case 4:
+ $thisfile_png_chunk_type_text['background_gray'] = getid3_lib::BigEndian2Int($chunk['data']);
+ break;
+
+ case 2:
+ case 6:
+ $thisfile_png_chunk_type_text['background_red'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0 * $thisfile_png['IHDR']['raw']['bit_depth'], $thisfile_png['IHDR']['raw']['bit_depth']));
+ $thisfile_png_chunk_type_text['background_green'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 1 * $thisfile_png['IHDR']['raw']['bit_depth'], $thisfile_png['IHDR']['raw']['bit_depth']));
+ $thisfile_png_chunk_type_text['background_blue'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 2 * $thisfile_png['IHDR']['raw']['bit_depth'], $thisfile_png['IHDR']['raw']['bit_depth']));
+ break;
+
+ case 3:
+ $thisfile_png_chunk_type_text['background_index'] = getid3_lib::BigEndian2Int($chunk['data']);
+ break;
+
+ default:
+ break;
+ }
+ break;
+
+
+ case 'pHYs': // Physical Pixel Dimensions
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ $thisfile_png_chunk_type_text['pixels_per_unit_x'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 4));
+ $thisfile_png_chunk_type_text['pixels_per_unit_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 4, 4));
+ $thisfile_png_chunk_type_text['unit_specifier'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 8, 1));
+ $thisfile_png_chunk_type_text['unit'] = $this->PNGpHYsUnitLookup($thisfile_png_chunk_type_text['unit_specifier']);
+ break;
+
+
+ case 'sBIT': // Significant Bits
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ switch ($thisfile_png['IHDR']['raw']['color_type']) {
+ case 0:
+ $thisfile_png_chunk_type_text['significant_bits_gray'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 1));
+ break;
+
+ case 2:
+ case 3:
+ $thisfile_png_chunk_type_text['significant_bits_red'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 1));
+ $thisfile_png_chunk_type_text['significant_bits_green'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 1, 1));
+ $thisfile_png_chunk_type_text['significant_bits_blue'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 2, 1));
+ break;
+
+ case 4:
+ $thisfile_png_chunk_type_text['significant_bits_gray'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 1));
+ $thisfile_png_chunk_type_text['significant_bits_alpha'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 1, 1));
+ break;
+
+ case 6:
+ $thisfile_png_chunk_type_text['significant_bits_red'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 1));
+ $thisfile_png_chunk_type_text['significant_bits_green'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 1, 1));
+ $thisfile_png_chunk_type_text['significant_bits_blue'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 2, 1));
+ $thisfile_png_chunk_type_text['significant_bits_alpha'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 3, 1));
+ break;
+
+ default:
+ break;
+ }
+ break;
+
+
+ case 'sPLT': // Suggested Palette
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ list($palettename, $otherdata) = explode("\x00", $chunk['data'], 2);
+ $thisfile_png_chunk_type_text['palette_name'] = $palettename;
+ $sPLToffset = 0;
+ $thisfile_png_chunk_type_text['sample_depth_bits'] = getid3_lib::BigEndian2Int(substr($otherdata, $sPLToffset, 1));
+ $sPLToffset += 1;
+ $thisfile_png_chunk_type_text['sample_depth_bytes'] = $thisfile_png_chunk_type_text['sample_depth_bits'] / 8;
+ $paletteCounter = 0;
+ while ($sPLToffset < strlen($otherdata)) {
+ $thisfile_png_chunk_type_text['red'][$paletteCounter] = getid3_lib::BigEndian2Int(substr($otherdata, $sPLToffset, $thisfile_png_chunk_type_text['sample_depth_bytes']));
+ $sPLToffset += $thisfile_png_chunk_type_text['sample_depth_bytes'];
+ $thisfile_png_chunk_type_text['green'][$paletteCounter] = getid3_lib::BigEndian2Int(substr($otherdata, $sPLToffset, $thisfile_png_chunk_type_text['sample_depth_bytes']));
+ $sPLToffset += $thisfile_png_chunk_type_text['sample_depth_bytes'];
+ $thisfile_png_chunk_type_text['blue'][$paletteCounter] = getid3_lib::BigEndian2Int(substr($otherdata, $sPLToffset, $thisfile_png_chunk_type_text['sample_depth_bytes']));
+ $sPLToffset += $thisfile_png_chunk_type_text['sample_depth_bytes'];
+ $thisfile_png_chunk_type_text['alpha'][$paletteCounter] = getid3_lib::BigEndian2Int(substr($otherdata, $sPLToffset, $thisfile_png_chunk_type_text['sample_depth_bytes']));
+ $sPLToffset += $thisfile_png_chunk_type_text['sample_depth_bytes'];
+ $thisfile_png_chunk_type_text['frequency'][$paletteCounter] = getid3_lib::BigEndian2Int(substr($otherdata, $sPLToffset, 2));
+ $sPLToffset += 2;
+ $paletteCounter++;
+ }
+ break;
+
+
+ case 'hIST': // Palette Histogram
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ $hISTcounter = 0;
+ while ($hISTcounter < strlen($chunk['data'])) {
+ $thisfile_png_chunk_type_text[$hISTcounter] = getid3_lib::BigEndian2Int(substr($chunk['data'], $hISTcounter / 2, 2));
+ $hISTcounter += 2;
+ }
+ break;
+
+
+ case 'tIME': // Image Last-Modification Time
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ $thisfile_png_chunk_type_text['year'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 2));
+ $thisfile_png_chunk_type_text['month'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 2, 1));
+ $thisfile_png_chunk_type_text['day'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 3, 1));
+ $thisfile_png_chunk_type_text['hour'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 4, 1));
+ $thisfile_png_chunk_type_text['minute'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 5, 1));
+ $thisfile_png_chunk_type_text['second'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 6, 1));
+ $thisfile_png_chunk_type_text['unix'] = gmmktime($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']);
+ break;
+
+
+ case 'oFFs': // Image Offset
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ $thisfile_png_chunk_type_text['position_x'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 4), false, true);
+ $thisfile_png_chunk_type_text['position_y'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 4, 4), false, true);
+ $thisfile_png_chunk_type_text['unit_specifier'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 8, 1));
+ $thisfile_png_chunk_type_text['unit'] = $this->PNGoFFsUnitLookup($thisfile_png_chunk_type_text['unit_specifier']);
+ break;
+
+
+ case 'pCAL': // Calibration Of Pixel Values
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ list($calibrationname, $otherdata) = explode("\x00", $chunk['data'], 2);
+ $thisfile_png_chunk_type_text['calibration_name'] = $calibrationname;
+ $pCALoffset = 0;
+ $thisfile_png_chunk_type_text['original_zero'] = getid3_lib::BigEndian2Int(substr($chunk['data'], $pCALoffset, 4), false, true);
+ $pCALoffset += 4;
+ $thisfile_png_chunk_type_text['original_max'] = getid3_lib::BigEndian2Int(substr($chunk['data'], $pCALoffset, 4), false, true);
+ $pCALoffset += 4;
+ $thisfile_png_chunk_type_text['equation_type'] = getid3_lib::BigEndian2Int(substr($chunk['data'], $pCALoffset, 1));
+ $pCALoffset += 1;
+ $thisfile_png_chunk_type_text['equation_type_text'] = $this->PNGpCALequationTypeLookup($thisfile_png_chunk_type_text['equation_type']);
+ $thisfile_png_chunk_type_text['parameter_count'] = getid3_lib::BigEndian2Int(substr($chunk['data'], $pCALoffset, 1));
+ $pCALoffset += 1;
+ $thisfile_png_chunk_type_text['parameters'] = explode("\x00", substr($chunk['data'], $pCALoffset));
+ break;
+
+
+ case 'sCAL': // Physical Scale Of Image Subject
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ $thisfile_png_chunk_type_text['unit_specifier'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 1));
+ $thisfile_png_chunk_type_text['unit'] = $this->PNGsCALUnitLookup($thisfile_png_chunk_type_text['unit_specifier']);
+ list($pixelwidth, $pixelheight) = explode("\x00", substr($chunk['data'], 1));
+ $thisfile_png_chunk_type_text['pixel_width'] = $pixelwidth;
+ $thisfile_png_chunk_type_text['pixel_height'] = $pixelheight;
+ break;
+
+
+ case 'gIFg': // GIF Graphic Control Extension
+ $gIFgCounter = 0;
+ if (isset($thisfile_png_chunk_type_text) && is_array($thisfile_png_chunk_type_text)) {
+ $gIFgCounter = count($thisfile_png_chunk_type_text);
+ }
+ $thisfile_png_chunk_type_text[$gIFgCounter]['header'] = $chunk;
+ $thisfile_png_chunk_type_text[$gIFgCounter]['disposal_method'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 1));
+ $thisfile_png_chunk_type_text[$gIFgCounter]['user_input_flag'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 1, 1));
+ $thisfile_png_chunk_type_text[$gIFgCounter]['delay_time'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 2, 2));
+ break;
+
+
+ case 'gIFx': // GIF Application Extension
+ $gIFxCounter = 0;
+ if (isset($thisfile_png_chunk_type_text) && is_array($thisfile_png_chunk_type_text)) {
+ $gIFxCounter = count($thisfile_png_chunk_type_text);
+ }
+ $thisfile_png_chunk_type_text[$gIFxCounter]['header'] = $chunk;
+ $thisfile_png_chunk_type_text[$gIFxCounter]['application_identifier'] = substr($chunk['data'], 0, 8);
+ $thisfile_png_chunk_type_text[$gIFxCounter]['authentication_code'] = substr($chunk['data'], 8, 3);
+ $thisfile_png_chunk_type_text[$gIFxCounter]['application_data'] = substr($chunk['data'], 11);
+ break;
+
+
+ case 'IDAT': // Image Data
+ $idatinformationfieldindex = 0;
+ if (isset($thisfile_png['IDAT']) && is_array($thisfile_png['IDAT'])) {
+ $idatinformationfieldindex = count($thisfile_png['IDAT']);
+ }
+ unset($chunk['data']);
+ $thisfile_png_chunk_type_text[$idatinformationfieldindex]['header'] = $chunk;
+ break;
+
+ case 'IEND': // Image Trailer
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ break;
+
+ case 'acTL': // Animation Control chunk
+ // https://wiki.mozilla.org/APNG_Specification#.60acTL.60:_The_Animation_Control_Chunk
+ $thisfile_png['animation']['num_frames'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 4)); // Number of frames
+ $thisfile_png['animation']['num_plays'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 4, 4)); // Number of times to loop this APNG. 0 indicates infinite looping.
+
+ unset($chunk['data']);
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ break;
+
+ case 'fcTL': // Frame Control chunk
+ // https://wiki.mozilla.org/APNG_Specification#.60fcTL.60:_The_Frame_Control_Chunk
+ $fcTL = array();
+ $fcTL['sequence_number'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 0, 4)); // Sequence number of the animation chunk, starting from 0
+ $fcTL['width'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 4, 4)); // Width of the following frame
+ $fcTL['height'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 8, 4)); // Height of the following frame
+ $fcTL['x_offset'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 12, 4)); // X position at which to render the following frame
+ $fcTL['y_offset'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 16, 4)); // Y position at which to render the following frame
+ $fcTL['delay_num'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 20, 2)); // Frame delay fraction numerator
+ $fcTL['delay_den'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 22, 2)); // Frame delay fraction numerator
+ $fcTL['dispose_op'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 23, 1)); // Type of frame area disposal to be done after rendering this frame
+ $fcTL['blend_op'] = getid3_lib::BigEndian2Int(substr($chunk['data'], 23, 1)); // Type of frame area rendering for this frame
+ if ($fcTL['delay_den']) {
+ $fcTL['delay'] = $fcTL['delay_num'] / $fcTL['delay_den'];
+ }
+ $thisfile_png['animation']['fcTL'][$fcTL['sequence_number']] = $fcTL;
+
+ unset($chunk['data']);
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ break;
+
+ case 'fdAT': // Frame Data chunk
+ // https://wiki.mozilla.org/APNG_Specification#.60fcTL.60:_The_Frame_Control_Chunk
+ // "The `fdAT` chunk has the same purpose as an `IDAT` chunk. It has the same structure as an `IDAT` chunk, except preceded by a sequence number."
+ unset($chunk['data']);
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ break;
+
+ default:
+ //unset($chunk['data']);
+ $thisfile_png_chunk_type_text['header'] = $chunk;
+ $this->warning('Unhandled chunk type: '.$chunk['type_text']);
+ break;
+ }
+ }
+ if (!empty($thisfile_png['animation']['num_frames']) && !empty($thisfile_png['animation']['fcTL'])) {
+ $info['video']['dataformat'] = 'apng';
+ $info['playtime_seconds'] = 0;
+ foreach ($thisfile_png['animation']['fcTL'] as $seqno => $fcTL) {
+ $info['playtime_seconds'] += $fcTL['delay'];
+ }
+ }
+ return true;
+ }
+
+ /**
+ * @param int $sRGB
+ *
+ * @return string
+ */
+ public function PNGsRGBintentLookup($sRGB) {
+ static $PNGsRGBintentLookup = array(
+ 0 => 'Perceptual',
+ 1 => 'Relative colorimetric',
+ 2 => 'Saturation',
+ 3 => 'Absolute colorimetric'
+ );
+ return (isset($PNGsRGBintentLookup[$sRGB]) ? $PNGsRGBintentLookup[$sRGB] : 'invalid');
+ }
+
+ /**
+ * @param int $compressionmethod
+ *
+ * @return string
+ */
+ public function PNGcompressionMethodLookup($compressionmethod) {
+ static $PNGcompressionMethodLookup = array(
+ 0 => 'deflate/inflate'
+ );
+ return (isset($PNGcompressionMethodLookup[$compressionmethod]) ? $PNGcompressionMethodLookup[$compressionmethod] : 'invalid');
+ }
+
+ /**
+ * @param int $unitid
+ *
+ * @return string
+ */
+ public function PNGpHYsUnitLookup($unitid) {
+ static $PNGpHYsUnitLookup = array(
+ 0 => 'unknown',
+ 1 => 'meter'
+ );
+ return (isset($PNGpHYsUnitLookup[$unitid]) ? $PNGpHYsUnitLookup[$unitid] : 'invalid');
+ }
+
+ /**
+ * @param int $unitid
+ *
+ * @return string
+ */
+ public function PNGoFFsUnitLookup($unitid) {
+ static $PNGoFFsUnitLookup = array(
+ 0 => 'pixel',
+ 1 => 'micrometer'
+ );
+ return (isset($PNGoFFsUnitLookup[$unitid]) ? $PNGoFFsUnitLookup[$unitid] : 'invalid');
+ }
+
+ /**
+ * @param int $equationtype
+ *
+ * @return string
+ */
+ public function PNGpCALequationTypeLookup($equationtype) {
+ static $PNGpCALequationTypeLookup = array(
+ 0 => 'Linear mapping',
+ 1 => 'Base-e exponential mapping',
+ 2 => 'Arbitrary-base exponential mapping',
+ 3 => 'Hyperbolic mapping'
+ );
+ return (isset($PNGpCALequationTypeLookup[$equationtype]) ? $PNGpCALequationTypeLookup[$equationtype] : 'invalid');
+ }
+
+ /**
+ * @param int $unitid
+ *
+ * @return string
+ */
+ public function PNGsCALUnitLookup($unitid) {
+ static $PNGsCALUnitLookup = array(
+ 0 => 'meter',
+ 1 => 'radian'
+ );
+ return (isset($PNGsCALUnitLookup[$unitid]) ? $PNGsCALUnitLookup[$unitid] : 'invalid');
+ }
+
+ /**
+ * @param int $color_type
+ * @param int $bit_depth
+ *
+ * @return int|false
+ */
+ public function IHDRcalculateBitsPerSample($color_type, $bit_depth) {
+ switch ($color_type) {
+ case 0: // Each pixel is a grayscale sample.
+ return $bit_depth;
+
+ case 2: // Each pixel is an R,G,B triple
+ return 3 * $bit_depth;
+
+ case 3: // Each pixel is a palette index; a PLTE chunk must appear.
+ return $bit_depth;
+
+ case 4: // Each pixel is a grayscale sample, followed by an alpha sample.
+ return 2 * $bit_depth;
+
+ case 6: // Each pixel is an R,G,B triple, followed by an alpha sample.
+ return 4 * $bit_depth;
+ }
+ return false;
+ }
+
+}