Algorithm

In the previous article, we discussed the RLE image compression algorithm used in PS2. This time, let’s delve into its texture mapping encoding algorithm—A1B5G5R5. Introduction For textures, common image encoding formats like jpg or png are not suitable. This is because images are read and rendered by the GPU. You wouldn’t want to send a jpg image over and have the GPU decode the entire image just to read one pixel, right? Therefore, the most ideal image format is an uncompressed bitmap format, allowing direct access to RGB data based on pixel coordinates. The A1B5G5R5 format we’re introducing today is one such encoding format. ...

Introduction to RLE Algorithm The RLE (Run Length Encoding) algorithm is a compression method that represents file content in the form of “number of repetitions x data.” For example: given the data AAAAAABBCDDEEEEEF, by appending the number of consecutive occurrences after each character, it can be represented as 6A2B1C2D5E1F. It can be observed that the original data is 17 bytes, while the encoded data is 12 bytes, thus achieving successful compression. ...