Convert bmp to raw Online: bmp2raw
You can use Tom's Editor to easily convert images from
Microsoft Windows bitmap .BMP to RAW Dump
Tom's Editor is a free, online image manipulation and converter program.
Go to Tom's Editor
Format created by Microsoft for their Windows and OS/2 operating systems. Images can be compressed or not.
This is just raw pixels saved in a file. Format used mostly by old games. RAW files do not have any header so if you don't know what is the original width and height of the image it might be hard to decode them.