Change background color of images in magento

I found the following solution for changing the background color of images. I have overwritten the Catalog/Helper/Image class, so the background color is changed in the whole theme and it isn’t necessary to overwrite the template files.

Create a class in app/code/local/Foo/Catalog/Helper/Image.php

class Foo_Catalog_Helper_Image extends Mage_Catalog_Helper_Image {
	public function init(Mage_Catalog_Model_Product $product,$attributeName,$imageFile = null) {
		parent::init($product,$attributeName,$imageFile);
		$this->backgroundColor(array(60,60,60));
		return $this;
	}
}

Overwriting the helper class in the app/code/local/Foo/Bar/etc/config.xml

<?xml version="1.0"?>
<config>
  <global>
    <helpers>
      <catalog>
        <rewrite>
          <image>Foo_Catalog_Helper_Image</image>
      </rewrite>
      </catalog>
    </helpers>
  </global>
</config>