Returns the value to use for image quality when creating jpeg images.

By default the quality is set to 75%. It is then run through the main jpeg_quality WordPress filter to add compatibility with other plugins that customise image quality. It is then run through the wpsc_jpeg_quality filter so that it is possible to override the quality setting just for WP e-Commerce Product images.

A plugin can alter the Product image quality with the code:

<?php add_filter( "wpsc_jpeg_quality", "plugin_function_name" ) ?>

Example of filter function:

* @param  $quality Image quality
function plugin_function_name($quality)
   $quality = 80;
   return $quality;