smushit.php

<?php
uses('folder');
uses('file');

class SmushitShell extends Shell {
	const service = 'http://smush.it/';

	function main() {
		$root = $this->params['root'] . DS;
		$src  = $this->args[0];
		if (substr($this->args[1], 0, 7) == 'http://') {
			$this->args[2] = $this->args[1];
			unset($this->args[1]);
		}
		if (!empty($this->args[1])) {
			$dest = $this->args[1];
		} else {
			$dest = $src . 'smushit' . DS;
		}
		$url = $this->args[2];

		$srcFolder = new Folder();

		if (!$srcFolder->cd($root . $src)) {
			$this->error('Invalid path', 'The path ' . $src . ' does not exists');
			return false;
		}
		// $destFolder = new Folder($root . $destFolder, true);

		$images = $srcFolder->findRecursive('[^._].*\.(jpg|gif|png)');
		$this->out('Smushing ' . count($images) . ' image(s)');

		$total = array(
			'src_size'  => 0,
			'dest_size' => 0
			);
		foreach ($images as $image) {
			if (strpos($image, $root . $dest) !== false) {
				continue;
			}

			$img     = $url . str_replace(array($root, DS), array('', '/'), $image);
			$imgPath = str_replace($root . $src, '', $image);
			$stats   = $this->_smush($img, $root . $dest . $imgPath, $image);

			if (!empty($stats->error)) {
				$this->out('Error: ' . $stats->error . "\t" . $imgPath);
			} else {
				$this->out($stats->src_size . "\t" . $stats->dest_size . "\t" . $stats->percent . "\t" . $imgPath . " -> " . basename($stats->dest));
				$total['src_size'] += $stats->src_size;
				$total['dest_size'] += $stats->dest_size;
			}
		}
		$percent = (100 * $total['dest_size']) / $total['src_size'];
		$savings = 100 - $percent;
		$this->out('Total:');
		$this->out("\tSrc size: " . $total['src_size']);
		$this->out("\tDst size: " . $total['dest_size']);
		$this->out("\tSavings:  " . round($savings, 2) . ' %');
	}

	function _smush($img, $dest, $src) {
		$url = SmushitShell::service . 'ws.php?img=' . $img;

		$handle = curl_init($url);
		ob_start();
		$return = curl_exec($handle);
		$output = ob_get_contents();
		ob_end_clean();

		$output = json_decode($output);

		if (empty($output->error)) {
			$handle = curl_init(SmushitShell::service . $output->dest);
			ob_start();
			curl_exec($handle);
			$content = ob_get_contents();
			ob_end_clean();

			new Folder(dirname($dest), true);
			$dest = dirname($dest) . DS . basename($output->dest);
			@unlink($dest);
			file_put_contents($dest, $content);
		}

		return $output;
	}
}

Nice idea!