Through bitter and hard won experience lately, I would say avoid JPG for games in Blitz (for sprites) for one very simple reason - as has previously pointed out, JPG is a lossy compression and what you see is not necesarilly what you get.
Let's say that you have an enemy sprite which has a purple background that you will later mask. With a JPG graphic, look closely at the purple background and you will see that there are artifacts introduced by the compression routines that you mask will not make transparent!
PNG is your friend (that said, I do use JPGs when I am not bothered about masking!)
Let's say that you have an enemy sprite which has a purple background that you will later mask. With a JPG graphic, look closely at the purple background and you will see that there are artifacts introduced by the compression routines that you mask will not make transparent!
PNG is your friend (that said, I do use JPGs when I am not bothered about masking!)