Convert bb4 to dds Online: bb42dds
You can use Tom's Editor to easily convert images from
Mode 4 .BB4 to Direct Show Surface
Tom's Editor is a free, online image manipulation and converter program.
Go to Tom's Editor
Mode 4 is an image format with extension BB4.
DDS are files invented by Microsoft to be used in games, mostly as textures. Images can be compressed to save space but the compression methods defined by DDS are all very fast in terms of coding and decoding.