I'm new to image processing and game development. I was following a tutorial in which it suggest to use background image of format
More detail on the colour space on Wikipedia and more information on bitmaps on Android Developers Documentation. A lpha, R ed, G reen and B lue channels are represented. The alpha channel denotes the level of transparency in the image. The '8' in the name refers to the number of bits per channel. So RGB is 8+8+8= 24 bits, and ARGB is 8+8+8+8 = 32 bits.
RGB will allow you to choose the colour of the image for either,
RGB888 assumes an alpha value of
255. Adding the Alpha value by using
ARGB8888 will allow you to set the transparency yourself with a number between 0 (fully transparent) and 255 (fully opaque). An example of adding transparency badly to a menu in Android would be something like the image below: