tcpdf_images.php

Go to the documentation of this file.

<?php
//============================================================+
// File name   : tcpdf_images.php
// Version     : 1.0.000
// Begin       : 2002-08-03
// Last Update : 2013-03-16
// Author      : Nicola Asuni - Tecnick.com LTD - www.tecnick.com - info@tecnick.com
// License     : GNU-LGPL v3 (http://www.gnu.org/copyleft/lesser.html)
// -------------------------------------------------------------------
// Copyright (C) 2002-2013 Nicola Asuni - Tecnick.com LTD
//
// This file is part of TCPDF software library.
//
// TCPDF is free software: you can redistribute it and/or modify it
// under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation, either version 3 of the
// License, or (at your option) any later version.
//
// TCPDF 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 Lesser General Public License for more details.
//
// You should have received a copy of the License
// along with TCPDF. If not, see
// <http://www.tecnick.com/pagefiles/tcpdf/LICENSE.TXT>.
//
// See LICENSE.TXT file for more information.
// -------------------------------------------------------------------
//
// Description :
//   Static image methods used by the TCPDF class.
//
//============================================================+
 
class TCPDF_IMAGES {
 
        public static $svginheritprop = array('clip-rule', 'color', 'color-interpolation', 'color-interpolation-filters', 'color-profile', 'color-rendering', 'cursor', 'direction', 'fill', 'fill-opacity', 'fill-rule', 'font', 'font-family', 'font-size', 'font-size-adjust', 'font-stretch', 'font-style', 'font-variant', 'font-weight', 'glyph-orientation-horizontal', 'glyph-orientation-vertical', 'image-rendering', 'kerning', 'letter-spacing', 'marker', 'marker-end', 'marker-mid', 'marker-start', 'pointer-events', 'shape-rendering', 'stroke', 'stroke-dasharray', 'stroke-dashoffset', 'stroke-linecap', 'stroke-linejoin', 'stroke-miterlimit', 'stroke-opacity', 'stroke-width', 'text-anchor', 'text-rendering', 'visibility', 'word-spacing', 'writing-mode');
 
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 
        public static function getImageFileType($imgfile, $iminfo=array()) {
                $type = '';
                if (isset($iminfo['mime']) AND !empty($iminfo['mime'])) {
                        $mime = explode('/', $iminfo['mime']);
                        if ((count($mime) > 1) AND ($mime[0] == 'image') AND (!empty($mime[1]))) {
                                $type = strtolower(trim($mime[1]));
                        }
                }
                if (empty($type)) {
                        $fileinfo = pathinfo($imgfile);
                        if (isset($fileinfo['extension']) AND (!TCPDF_STATIC::empty_string($fileinfo['extension']))) {
                                $type = strtolower(trim($fileinfo['extension']));
                        }
                }
                if ($type == 'jpg') {
                        $type = 'jpeg';
                }
                return $type;
        }
 
        public static function setGDImageTransparency($new_image, $image) {
                // transparency index
                $tid = imagecolortransparent($image);
                // default transparency color
                $tcol = array('red' => 255, 'green' => 255, 'blue' => 255);
                if ($tid >= 0) {
                        // get the colors for the transparency index
                        $tcol = imagecolorsforindex($image, $tid);
                }
                $tid = imagecolorallocate($new_image, $tcol['red'], $tcol['green'], $tcol['blue']);
                imagefill($new_image, 0, 0, $tid);
                imagecolortransparent($new_image, $tid);
                return $new_image;
        }
 
        public static function _toPNG($image) {
                // set temporary image file name
                $tempname = TCPDF_STATIC::getObjFilename('png');
                // turn off interlaced mode
                imageinterlace($image, 0);
                // create temporary PNG image
                imagepng($image, $tempname);
                // remove image from memory
                imagedestroy($image);
                // get PNG image data
                $retvars = self::_parsepng($tempname);
                // tidy up by removing temporary image
                unlink($tempname);
                return $retvars;
        }
 
        public static function _toJPEG($image, $quality) {
                $tempname = TCPDF_STATIC::getObjFilename('jpg');
                imagejpeg($image, $tempname, $quality);
                imagedestroy($image);
                $retvars = self::_parsejpeg($tempname);
                // tidy up by removing temporary image
                unlink($tempname);
                return $retvars;
        }
 
        public static function _parsejpeg($file) {
                $a = getimagesize($file);
                if (empty($a)) {
                        //Missing or incorrect image file
                        return false;
                }
                if ($a[2] != 2) {
                        // Not a JPEG file
                        return false;
                }
                // bits per pixel
                $bpc = isset($a['bits']) ? intval($a['bits']) : 8;
                // number of image channels
                if (!isset($a['channels'])) {
                        $channels = 3;
                } else {
                        $channels = intval($a['channels']);
                }
                // default colour space
                switch ($channels) {
                        case 1: {
                                $colspace = 'DeviceGray';
                                break;
                        }
                        case 3: {
                                $colspace = 'DeviceRGB';
                                break;
                        }
                        case 4: {
                                $colspace = 'DeviceCMYK';
                                break;
                        }
                        default: {
                                $channels = 3;
                                $colspace = 'DeviceRGB';
                                break;
                        }
                }
                // get file content
                $data = file_get_contents($file);
                // check for embedded ICC profile
                $icc = array();
                $offset = 0;
                while (($pos = strpos($data, "ICC_PROFILE\0", $offset)) !== false) {
                        // get ICC sequence length
                        $length = (TCPDF_STATIC::_getUSHORT($data, ($pos - 2)) - 16);
                        // marker sequence number
                        $msn = max(1, ord($data[($pos + 12)]));
                        // number of markers (total of APP2 used)
                        $nom = max(1, ord($data[($pos + 13)]));
                        // get sequence segment
                        $icc[($msn - 1)] = substr($data, ($pos + 14), $length);
                        // move forward to next sequence
                        $offset = ($pos + 14 + $length);
                }
                // order and compact ICC segments
                if (count($icc) > 0) {
                        ksort($icc);
                        $icc = implode('', $icc);
                        if ((ord($icc{36}) != 0x61) OR (ord($icc{37}) != 0x63) OR (ord($icc{38}) != 0x73) OR (ord($icc{39}) != 0x70)) {
                                // invalid ICC profile
                                $icc = false;
                        }
                } else {
                        $icc = false;
                }
                return array('w' => $a[0], 'h' => $a[1], 'ch' => $channels, 'icc' => $icc, 'cs' => $colspace, 'bpc' => $bpc, 'f' => 'DCTDecode', 'data' => $data);
        }
 
        public static function _parsepng($file) {
                $f = fopen($file, 'rb');
                if ($f === false) {
                        // Can't open image file
                        return false;
                }
                //Check signature
                if (fread($f, 8) != chr(137).'PNG'.chr(13).chr(10).chr(26).chr(10)) {
                        // Not a PNG file
                        return false;
                }
                //Read header chunk
                fread($f, 4);
                if (fread($f, 4) != 'IHDR') {
                        //Incorrect PNG file
                        return false;
                }
                $w = TCPDF_STATIC::_freadint($f);
                $h = TCPDF_STATIC::_freadint($f);
                $bpc = ord(fread($f, 1));
                if ($bpc > 8) {
                        // 16-bit depth not supported
                        fclose($f);
                        return false;
                }
                $ct = ord(fread($f, 1));
                if ($ct == 0) {
                        $colspace = 'DeviceGray';
                } elseif ($ct == 2) {
                        $colspace = 'DeviceRGB';
                } elseif ($ct == 3) {
                        $colspace = 'Indexed';
                } else {
                        // alpha channel
                        fclose($f);
                        return 'pngalpha';
                }
                if (ord(fread($f, 1)) != 0) {
                        // Unknown compression method
                        fclose($f);
                        return false;
                }
                if (ord(fread($f, 1)) != 0) {
                        // Unknown filter method
                        fclose($f);
                        return false;
                }
                if (ord(fread($f, 1)) != 0) {
                        // Interlacing not supported
                        fclose($f);
                        return false;
                }
                fread($f, 4);
                $channels = ($ct == 2 ? 3 : 1);
                $parms = '/DecodeParms << /Predictor 15 /Colors '.$channels.' /BitsPerComponent '.$bpc.' /Columns '.$w.' >>';
                //Scan chunks looking for palette, transparency and image data
                $pal = '';
                $trns = '';
                $data = '';
                $icc = false;
                do {
                        $n = TCPDF_STATIC::_freadint($f);
                        $type = fread($f, 4);
                        if ($type == 'PLTE') {
                                // read palette
                                $pal = TCPDF_STATIC::rfread($f, $n);
                                fread($f, 4);
                        } elseif ($type == 'tRNS') {
                                // read transparency info
                                $t = TCPDF_STATIC::rfread($f, $n);
                                if ($ct == 0) {
                                        $trns = array(ord($t{1}));
                                } elseif ($ct == 2) {
                                        $trns = array(ord($t{1}), ord($t{3}), ord($t{5}));
                                } else {
                                        $pos = strpos($t, chr(0));
                                        if ($pos !== false) {
                                                $trns = array($pos);
                                        }
                                }
                                fread($f, 4);
                        } elseif ($type == 'IDAT') {
                                // read image data block
                                $data .= TCPDF_STATIC::rfread($f, $n);
                                fread($f, 4);
                        } elseif ($type == 'iCCP') {
                                // skip profile name
                                $len = 0;
                                while ((ord(fread($f, 1)) > 0) AND ($len < 80)) {
                                        ++$len;
                                }
                                // skip null separator
                                fread($f, 1);
                                // get compression method
                                if (ord(fread($f, 1)) != 0) {
                                        // Unknown filter method
                                        fclose($f);
                                        return false;
                                }
                                // read ICC Color Profile
                                $icc = TCPDF_STATIC::rfread($f, ($n - $len - 2));
                                // decompress profile
                                $icc = gzuncompress($icc);
                                fread($f, 4);
                        } elseif ($type == 'IEND') {
                                break;
                        } else {
                                TCPDF_STATIC::rfread($f, $n + 4);
                        }
                } while ($n);
                if (($colspace == 'Indexed') AND (empty($pal))) {
                        // Missing palette
                        fclose($f);
                        return false;
                }
                fclose($f);
                return array('w' => $w, 'h' => $h, 'ch' => $channels, 'icc' => $icc, 'cs' => $colspace, 'bpc' => $bpc, 'f' => 'FlateDecode', 'parms' => $parms, 'pal' => $pal, 'trns' => $trns, 'data' => $data);
        }
 
} // END OF TCPDF_STATIC CLASS
 
//============================================================+
// END OF FILE
//============================================================+