Possibility of using PNG Files to change Folder default icon

Is it possible to do this ? Use a png file to change the default folder icon ?? I would like to change my GPSoftware/Directory Opus folder icon to a folder icon that has the opus 8 logo on it. It is just eye candy but I think it would be kinda cool to do. Like the folder icons found in AEon's Miscellaneous Icons pack. But these are png files... See my problem ?? Thanks in advance

I think they have to be jpg files at the moment.

That said, if you rename a png file folder.jpg it'll still be used as the folder image even though the extension is wrong.

It works in Explorer, too.

Thanks for quick reply... I'll give it a try