> the images on the page change with every request based on the item specifics, therefore combining them into one sprite image is not possible.
It is very possible. Just include the sprite dimensional and positional info in an inline CSS stylesheet on the page and generate a sprite sheet as you would normally. Base64 data: URIs add tons of overhead which will definitely end up being much slower. Not to mention that they're using PNG when they should be using JPEG, which just worsens the issue even more.
It is very possible. Just include the sprite dimensional and positional info in an inline CSS stylesheet on the page and generate a sprite sheet as you would normally. Base64 data: URIs add tons of overhead which will definitely end up being much slower. Not to mention that they're using PNG when they should be using JPEG, which just worsens the issue even more.