<?
/*
 * usage:
 * resize.php [destination_width] [destination_height]
 *
 * destination_width and destination_height are optional
 * parameters for destination resize geometry
 *
 * resize.php will create output directory to save resized
 * images leaving originals intact
 *
 * This script uses "identify" and "convert" utilities which
 * are members of the ImageMagick suite of tools
 *
 */

// input arguments for destination image size
$w2 = $argv[1]; // image width
$h2 = $argv[2]; // image height

// both values should be numeric or use default size 800x600
if (!is_numeric($w2) || !is_numeric($h2)){
	$w2 = 138; // default image width
	$h2 = 82; // default image height
}

// prepare directory name for saving resized images
// directory name will look like "_800x600"
$dir = "_$w2" . "x$h2";

// create directory (inside current directory) for saving
// resized images (@ means to be quiet - don't display
// warning if directory alredy exists)
@mkdir($dir);

// read files inside current directory
$files = scandir('.');

// open loop for all fetched files in current directory
foreach ($files as $file){
	// convert file name to lower case
	$file_lowercase = strtolower($file);
	// if file extension is jpg then process image
	if (substr($file_lowercase, -3) == 'jpg'){
		// describe image format and image characteristics
		$identify = shell_exec("identify $file");
		// read image geometry
		preg_match('/(\d+)x(\d+)/', $identify, $matches);
		$g1 = $matches[0]; // image geometry
		$w1 = $matches[1]; // image width
		$h1 = $matches[2]; // image height
		// prepare destination image geometry
		if ($w1 < $h1) $g2 = $h2 .'x' .$w2;
		else           $g2 = $w2 .'x' .$h2;
		// print current image status
		print "$file ($g1) -> $dir/$file_lowercase ($g2)\n";
		// resize image and save to destination directory
		system("convert -size $g1 $file -resize $g2 $dir/$file_lowercase");
	}
}
?>