pdf2jpeg PHP

<?php
    function genPdfThumbnail($source, $target)
    {

        // Max vert or horiz resolution
        $maxsize=550;

        // Create object
        $im     = new Imagick($source."[0]"); // 0-first page, 1-second page

        // Resolution
        //$im->setImageUnits(imagick::RESOLUTION_PIXELSPERINCH);
        //$im->setResolution(300, 300);
        //$imageResolution = $im->getImageResolution();
        //print_r($imageResolution);

        $im->readImage($source."[0]");  //Open after setting resolution.

        //$im->setImageBackgroundColor('white');
        // Avoid any funny business with colours and inverted alphas
        $im = $im->mergeImageLayers(Imagick::LAYERMETHOD_FLATTEN);

        // Type and quality
        $im->setimageformat("jpeg");
        $im->setImageCompressionQuality(75);
        //$im->setImageCompression(imagick::COMPRESSION_JPEG);
        //$im->thumbnailimage(1240, 1754, true, true); // width and height [Print Quality]

        // Resizes to whichever is larger, width or height
        if($im->getImageHeight() <= $im->getImageWidth())
        {
            // Resize image using the lanczos resampling algorithm based on width
            $im->resizeImage($maxsize,0,Imagick::FILTER_LANCZOS,1);
        }
        else
        {
            // Resize image using the lanczos resampling algorithm based on height
            $im->resizeImage(0,$maxsize,Imagick::FILTER_LANCZOS,1);
        }

        // Strip out unneeded meta data
        $im->stripImage();

        $im->writeimage($target);
        $im->clear();
        $im->destroy();
    }

// genPdfThumbnail('/uploads/my.pdf','my.jpg'); // generates /uploads/my.jpg


foreach ($argv as $arg) {
    $e=explode("=",$arg);
    if(count($e)==2)
        $_GET[$e[0]]=$e[1];
    else
        $_GET[$e[0]]=0;
}

// Set the output directory
$outputDir = "/images/thumbs/";

// Get a list of files and directories, excluding parent and current
$allFiles =     array_diff( scandir( $e[0] ), array('..','.') );

// Get a list of sub-directories to filter
$allDirs =      array_filter( $allFiles, "is_dir" );

// Create an array with just the files in the current directory
$files =        array_diff( $allFiles, $allDirs );

// Now filter for PDFs
foreach($files as $file => $pdf)
{
    if(strpos($pdf, '.pdf') == false)
        unset($files[$file]);
}

// Re-index the array, starting from [0]
$files = array_values($files);

$i = 0;

foreach($files as $file)
{
    if(is_file($e[0].$file)){
        $output_file = $outputDir . pathinfo($file, PATHINFO_FILENAME) . ".jpg";
        $source_file = $e[0].$file;
        genPdfThumbnail($source_file, $output_file);
        echo $output_file . " ...generated" . "\n";
        ++$i;
    }
}

echo "Completed " . $i . " files";
?>