class.ilGhostscriptRenderer.php

Go to the documentation of this file.

<?php
/* Copyright (c) 1998-2013 ILIAS open source, Extended GPL, see docs/LICENSE */
 
include_once("./Services/Preview/classes/class.ilFilePreviewRenderer.php");
 
class ilGhostscriptRenderer extends ilFilePreviewRenderer
{
        // constants
        const SUPPORTED_FORMATS = "eps,pdf,pdfa,ps";
        
        // variables
        private static $supported_formats = null;
        
        public function getSupportedFileFormats()
        {
                // build formats only once
                if (self::$supported_formats == null)
                        self::$supported_formats = explode(",", self::SUPPORTED_FORMATS);
                
                return self::$supported_formats;
        }
        
        public static function isGhostscriptInstalled()
        {
                return (PATH_TO_GHOSTSCRIPT != "");
        }
        
        protected function renderImages($obj)
        {
                $numOfPreviews = $this->getMaximumNumberOfPreviews();
                
                // get file path
                $filepath = $obj->getFile();
                $inputFile = $this->prepareFileForExec($filepath);
                
                // create a temporary file name and remove its extension
                $output = str_replace(".tmp", "", ilUtil::ilTempnam());
                
                // use '#' instead of '%' as it gets replaced by 'escapeShellArg' on windows!
                $outputFile = $output . "_#02d.png";            
 
                // create images with ghostscript (we use PNG here as it has better transparency quality)
                // gswin32c -dBATCH -dNOPAUSE -dSAFER -dFirstPage=1 -dLastPage=5 -sDEVICE=pngalpha -dEPSCrop -r72 -o $outputFile $inputFile
                // gswin32c -dBATCH -dNOPAUSE -dSAFER -dFirstPage=1 -dLastPage=5 -sDEVICE=jpeg -dJPEGQ=90 -r72 -o $outputFile $inputFile
                $args = sprintf(
                        "-dBATCH -dNOPAUSE -dSAFER -dFirstPage=1 -dLastPage=%d -sDEVICE=pngalpha -dEPSCrop -r72 -o %s %s",
                        $numOfPreviews,
                        str_replace("#", "%", ilUtil::escapeShellArg($outputFile)),
                        ilUtil::escapeShellArg($inputFile));
                
                ilUtil::execQuoted(PATH_TO_GHOSTSCRIPT, $args);
                
                // was a temporary file created? then delete it
                if ($filepath != $inputFile)
                        @unlink($inputFile);
                
                // check each file and add it
                $images = array();
                $outputFile = str_replace("#", "%", $outputFile);
                
                for ($i = 1; $i <= $numOfPreviews; $i++)
                {
                        $imagePath = sprintf($outputFile, $i);  
                        if (!file_exists($imagePath))
                                break;
                        
                        $images[] = new ilRenderedImage($imagePath);
                }
                
                return $images;
        }
}
?>