4x8 Font

Hi Gordon - I've been puzzling over modifying this code to make a slightly bigger font than 4x8 and I'm rather stuck. (I have a nice bitmap font that doesn't convert well from OTF, and I want to encode the numbers from scratch using a method like this). Can you give me a clue as to what this line is doing? I understand the bitwise operators and can see the numbers in the console but I'm puzzled as to their significance.

 var i = (col&3)+((col&~3)<<3);