PNGU version 0.2b has been released, here is some information about it:
PNGU is a library for Wii and GameCube that ‘wraps’ the famous libpng and facilitate png handling and conversions to the native Wii/GC formats. The PNG format has some properties which make it interesting: A background color, a list of transparent colors, alpha channel, it doesn’t modify the colors (as jpeg does when compression), open format. The source code of the library is included in the download package.
- It’s based in libpng 1.2.29
- Handles images of 8 and 16 bits per channel.
- Handles images in RGB, RGBA, grayscale and grayscale + alpha formats.
- Reads image dimensions, pixel format, background color and transparent colors list.
- Converts images to YCbYCr, linear RGB565, linear RGBA8, 4×4 RGB565, 4×4 RGB5A3 and 4×4 RGBA8 formats.
- Saves YCbYCr images in png RGB8 format.
- Handles images stored in memory or in devoptab devices (SD, Gecko SD, etc…).
- It’s ready to be used in multithreaded applications.