Convert bb4 to gif Online: bb42gif
You can use Tom's Editor to easily convert images from
Mode 4 .BB4 to CompuServe Graphics Interchange Format .GIF.
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.
GIF images were created by Compuserve. They can used no more than 256 colors and a single color transparenty (no Alpha channel). Today are rare since they offer low quality and huge filesizes. GIF animations are still in use.