OK, I have a weird problem...
I load a PNG that has transparency (not different levels, just on or off).
I then extract individual tiles from this using...
Image.createImage(f_data, xpos, ypos, width, height, 0);
All the tiles are fine, and retain the transparent background, but a couple of the tiles have solid white backgrounds. There appears to be nothing wrong with the PNG when I check it in Photoshop.
This is using MIDP2 only. It works fine in all emulators, but on a real Nokia N73 the odd tile has a solid white background.
Is there is limit on the width or size of PNG's