A Wordpress plugin to compress png-images.
An Ubuntu server with pngquant installed.
CompressPics hooks into wp_generate_attachment_metadata to compress the images once they're saved or updated. Once ResponsivePics resized the images and responsive_pics_file_saved_local fires, CompressPics will compress the newly generated images.
It is possible to force a compression through the WP CLI through a set of commands.
To compress the featured image of a post you can insert the post id:
wp cpics compress --post=<POST_ID>
To specify which image to compress you can insert the image id:
wp cpics compress --image=<IMAGE_ID>
In order to compress all images asociated to a product and its variations insert the product id:
wp cpics compress --product=<PRODUCT_ID>