File Content: PelJpegMarker.php <?php /* * PEL: PHP Exif Library. * A library with support for reading and * writing all Exif headers in JPEG and TIFF images using PHP. * * Copyright (C) 2004, 2006 Martin Geisler. * Copyright (C) 2017 Johannes Weberhofer. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program in the file COPYING; if not, write to the * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, * Boston, MA 02110-1301 USA */ /** * Classes for dealing with JPEG markers. * * This class defines the constants to be used whenever one refers to * a JPEG marker. All the methods defined are static, and they all * operate on one argument which should be one of the class constants. * They will all be denoted by PelJpegMarker in the documentation. * * @author Martin Geisler <mgeisler@users.sourceforge.net> * @author Johannes Weberhofer <jweberhofer@weberhofer.at> * @license http://www.gnu.org/licenses/gpl.html GNU General Public * License (GPL) * @package PEL */ namespace lsolesen\pel; class PelJpegMarker { /** * Encoding (baseline) */ const SOF0 = 0xC0; /** * Encoding (extended sequential) */ const SOF1 = 0xC1; /** * Encoding (progressive) */ const SOF2 = 0xC2; /** * Encoding (lossless) */ const SOF3 = 0xC3; /** * Define Huffman table */ const DHT = 0xC4; /** * Encoding (differential sequential) */ const SOF5 = 0xC5; /** * Encoding (differential progressive) */ const SOF6 = 0xC6; /** * Encoding (differential lossless) */ const SOF7 = 0xC7; /** * Extension */ const JPG = 0xC8; /** * Encoding (extended sequential, arithmetic) */ const SOF9 = 0xC9; /** * Encoding (progressive, arithmetic) */ const SOF10 = 0xCA; /** * Encoding (lossless, arithmetic) */ const SOF11 = 0xCB; /** * Define arithmetic coding conditioning */ const DAC = 0xCC; /** * Encoding (differential sequential, arithmetic) */ const SOF13 = 0xCD; /** * Encoding (differential progressive, arithmetic) */ const SOF14 = 0xCE; /** * Encoding (differential lossless, arithmetic) */ const SOF15 = 0xCF; /** * Restart 0 */ const RST0 = 0xD0; /** * Restart 1 */ const RST1 = 0xD1; /** * Restart 2 */ const RST2 = 0xD2; /** * Restart 3 */ const RST3 = 0xD3; /** * Restart 4 */ const RST4 = 0xD4; /** * Restart 5 */ const RST5 = 0xD5; /** * Restart 6 */ const RST6 = 0xD6; /** * Restart 7 */ const RST7 = 0xD7; /** * Start of image */ const SOI = 0xD8; /** * End of image */ const EOI = 0xD9; /** * Start of scan */ const SOS = 0xDA; /** * Define quantization table */ const DQT = 0xDB; /** * Define number of lines */ const DNL = 0xDC; /** * Define restart interval */ const DRI = 0xDD; /** * Define hierarchical progression */ const DHP = 0xDE; /** * Expand reference component */ const EXP = 0xDF; /** * Application segment 0 */ const APP0 = 0xE0; /** * Application segment 1 * * When a JPEG image contains Exif data, the data will normally be * stored in this section and a call to {@link PelJpeg::getExif()} * will return a {@link PelExif} object representing it. */ const APP1 = 0xE1; /** * Application segment 2 */ const APP2 = 0xE2; /** * Application segment 3 */ const APP3 = 0xE3; /** * Application segment 4 */ const APP4 = 0xE4; /** * Application segment 5 */ const APP5 = 0xE5; /** * Application segment 6 */ const APP6 = 0xE6; /** * Application segment 7 */ const APP7 = 0xE7; /** * Application segment 8 */ const APP8 = 0xE8; /** * Application segment 9 */ const APP9 = 0xE9; /** * Application segment 10 */ const APP10 = 0xEA; /** * Application segment 11 */ const APP11 = 0xEB; /** * Application segment 12 */ const APP12 = 0xEC; /** * Application segment 13 */ const APP13 = 0xED; /** * Application segment 14 */ const APP14 = 0xEE; /** * Application segment 15 */ const APP15 = 0xEF; /** * Extension 0 */ const JPG0 = 0xF0; /** * Extension 1 */ const JPG1 = 0xF1; /** * Extension 2 */ const JPG2 = 0xF2; /** * Extension 3 */ const JPG3 = 0xF3; /** * Extension 4 */ const JPG4 = 0xF4; /** * Extension 5 */ const JPG5 = 0xF5; /** * Extension 6 */ const JPG6 = 0xF6; /** * Extension 7 */ const JPG7 = 0xF7; /** * Extension 8 */ const JPG8 = 0xF8; /** * Extension 9 */ const JPG9 = 0xF9; /** * Extension 10 */ const JPG10 = 0xFA; /** * Extension 11 */ const JPG11 = 0xFB; /** * Extension 12 */ const JPG12 = 0xFC; /** * Extension 13 */ const JPG13 = 0xFD; /** * Comment */ const COM = 0xFE; /** * Values for marker's short names */ protected static $jpegMarkerShort = [ self::SOF0 => 'SOF0', self::SOF1 => 'SOF1', self::SOF2 => 'SOF2', self::SOF3 => 'SOF3', self::SOF5 => 'SOF5', self::SOF6 => 'SOF6', self::SOF7 => 'SOF7', self::SOF9 => 'SOF9', self::SOF10 => 'SOF10', self::SOF11 => 'SOF11', self::SOF13 => 'SOF13', self::SOF14 => 'SOF14', self::SOF15 => 'SOF15', self::SOI => 'SOI', self::EOI => 'EOI', self::SOS => 'SOS', self::COM => 'COM', self::DHT => 'DHT', self::JPG => 'JPG', self::DAC => 'DAC', self::RST0 => 'RST0', self::RST1 => 'RST1', self::RST2 => 'RST2', self::RST3 => 'RST3', self::RST4 => 'RST4', self::RST5 => 'RST5', self::RST6 => 'RST6', self::RST7 => 'RST7', self::DQT => 'DQT', self::DNL => 'DNL', self::DRI => 'DRI', self::DHP => 'DHP', self::EXP => 'EXP', self::APP0 => 'APP0', self::APP1 => 'APP1', self::APP2 => 'APP2', self::APP3 => 'APP3', self::APP4 => 'APP4', self::APP5 => 'APP5', self::APP6 => 'APP6', self::APP7 => 'APP7', self::APP8 => 'APP8', self::APP9 => 'APP9', self::APP10 => 'APP10', self::APP11 => 'APP11', self::APP12 => 'APP12', self::APP13 => 'APP13', self::APP14 => 'APP14', self::APP15 => 'APP15', self::JPG0 => 'JPG0', self::JPG1 => 'JPG1', self::JPG2 => 'JPG2', self::JPG3 => 'JPG3', self::JPG4 => 'JPG4', self::JPG5 => 'JPG5', self::JPG6 => 'JPG6', self::JPG7 => 'JPG7', self::JPG8 => 'JPG8', self::JPG9 => 'JPG9', self::JPG10 => 'JPG10', self::JPG11 => 'JPG11', self::JPG12 => 'JPG12', self::JPG13 => 'JPG13' ]; /** * Values for marker's descriptions names. */ protected static $jpegMarkerDescriptions = [ self::SOF0 => 'Encoding (baseline)', self::SOF1 => 'Encoding (extended sequential)', self::SOF2 => 'Encoding (progressive)', self::SOF3 => 'Encoding (lossless)', self::SOF5 => 'Encoding (differential sequential)', self::SOF6 => 'Encoding (differential progressive)', self::SOF7 => 'Encoding (differential lossless)', self::SOF9 => 'Encoding (extended sequential, arithmetic)', self::SOF10 => 'Encoding (progressive, arithmetic)', self::SOF11 => 'Encoding (lossless, arithmetic)', self::SOF13 => 'Encoding (differential sequential, arithmetic)', self::SOF14 => 'Encoding (differential progressive, arithmetic)', self::SOF15 => 'Encoding (differential lossless, arithmetic)', self::SOI => 'Start of image', self::EOI => 'End of image', self::SOS => 'Start of scan', self::COM => 'Comment', self::DHT => 'Define Huffman table', self::JPG => 'Extension', self::DAC => 'Define arithmetic coding conditioning', 'RST' => 'Restart %d', self::DQT => 'Define quantization table', self::DNL => 'Define number of lines', self::DRI => 'Define restart interval', self::DHP => 'Define hierarchical progression', self::EXP => 'Expand reference component', 'APP' => 'Application segment %d', 'JPG' => 'Extension %d', ]; /** * Check if a byte is a valid JPEG marker. * If the byte is recognized true is returned, otherwise false will be returned. * * @param integer $marker * the marker as defined in {@link PelJpegMarker} * @return boolean */ public static function isValid($marker) { return ($marker >= self::SOF0 && $marker <= self::COM); } /** * Turn a JPEG marker into bytes. * This will be a string with just a single byte since all JPEG markers are simply single bytes. * * @param integer $marker * the marker as defined in {@link PelJpegMarker} * @return string */ public static function getBytes($marker) { return chr($marker); } /** * Return the short name for a marker, e.g., 'SOI' for the Start * of Image marker. * * @param integer $marker * the marker as defined in {@link PelJpegMarker} * @return string */ public static function getName($marker) { if (array_key_exists($marker, self::$jpegMarkerShort)) { return self::$jpegMarkerShort[$marker]; } else { return Pel::fmt('Unknown marker: 0x%02X', $marker); } } /** * Returns a description of a JPEG marker. * * @param integer $marker * the marker as defined in {@link PelJpegMarker} * @return string */ public static function getDescription($marker) { if (array_key_exists($marker, self::$jpegMarkerShort)) { if (array_key_exists($marker, self::$jpegMarkerDescriptions)) { return self::$jpegMarkerDescriptions[$marker]; } else { $splitted = preg_split("/(\d+)/", self::$jpegMarkerShort[$marker], - 1, PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE); if ((count($splitted) == 2) && array_key_exists($splitted[0], self::$jpegMarkerDescriptions)) { return Pel::fmt(self::$jpegMarkerDescriptions[$splitted[0]], $splitted[1]); } } } return Pel::fmt('Unknown marker: 0x%02X', $marker); } } Submit