How do I get transparency in a .png?
PNG transparency is a bit more complicated than GIF transparency. PNG can use a transparent color in images with no more than 256 colors (palette images), and it supports an “alpha channel”, which specifies how transparent each pixel is supposed to be. Possible values range from 0 (opaque) to 255 (completely transparent). PNG can also assign a different transparency value to each color in a palette, but PSP does not appear to be able to take advantage of that. For a palette (256 or fewer colors) PNG, transparency consists of selecting a transparent color, and saving it, just like in GIFs. For a 16.7-million (24-bit) color PNG, transparency comes from an alpha channel. This works like a mask in Paint Shop Pro, and PSP uses masks to do this job with PNGs. To save an alpha channel with a 16.7-million color PNG, create a mask that gives you the desired transparency, and save the file. If you open a PNG with alpha channel information, PSP converts this to a mask.
