TODO.txt

TODO (apart from make the thing work)
	* On hover of middle and right canvases, show wrong pixels in white and right pixels in black. Maybe use the value of pixel to indicate the size of the error? (An option)
	* Store settings with a cookie?
	* Add in the remaining codes
	* Compute the diffs (in main thread) on mouse enter and leave;
	* Or compute the diffs in workers?
	* Lower the bits per pixel as an option?
	* Better UI on mobiles?
	* Maybe it should display the number of bits which go through correctly? (The problem I'm getting at hear is that the application doesn't distinguish between low-significance and high-significance bit errors. 2 -> 3 and 2 -> 130 are both 1 bit errors in bytes, but they'll rapdily distort the image.)
	* Mobile UI: add arrows to indicate that you need to swipe horizontally (vertically) in portait (landscape) mode? Or let users swipe rather than scroll between tiles? See https://developers.google.com/web/fundamentals/design-and-ux/input/touch/