Resize images with PHP script

This small command line PHP script will help you to resize all JPG images inside current directory. Yes, you will find a lot of solutions with BASH scripts, but I decided to write my own command line PHP script. I didn't want to use GD PHP functions for image processing. 

Instead of GD library, I used utilities from ImageMagick suite of tools: identifyand convert. This way, PHP script is shorter and easier to understand.

• identify - describes the format and characteristics of one or more image files
• convert - convert between image formats as well as resize an image, blur, crop, despeckle, dither, draw on, flip, join, re-sample, and much more

Script was developed on Linux - Fedora Core 9 and tested on Fedora Core 9 and Fedora Core 10.

#!/usr/bin/php

<?

/*

 * 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 = 800; // default image width

    $h2 = 600; // 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");

    }

}

?>

If you want to try script, please save PHP code as resize.php. Set permissions to 755 and you can start resize.php like any script from the shell.

Enjoy!