Bitmap images can be readily converted to Arduino friendly source here:

http://javl.github.io/image2cpp/  

OR 

just run image2cpp.html in your browser


Step 1:
         Select a file from your PC (preferably monochrome bitmap)

Step 2:
         Backgorund colour:    Black
         Invert Image colours: Selected
         Brightness threshold: 128
         Centering:            OFF
       
Step 4:
         Format:      Arduino Code
         Identifier:  The name you'd like to use (can be post edited!)
         Draw Mode:   Horizontal
         
Press Generate code, then copy n paste to the source file