24-bit BufferedImage with bitmask-transparency?

[lupokehl42]

Hello,

I'm trying to create a BufferedImage with 24-bit color depth (not 8-bit indexed) and a single transparent color. Such an image ought to perform much better than one with an 8-bit alpha channel (which on my PC is about 20 times slower than an opaque image).

The problem is: When loading a 24-bit PNG file with colorkey transparency (via ImageIO.read(...) ), the transparency is converted to an 8-bit alpha channel.
Besides, I couldn't find a way to create an empty BufferedImage with these settings, either.

I am sure there must be a way, since this format (24-bit with color-key) is quite popular with other graphics engines.
I'd be glad about any help.

Thanks
Daniel