[kyberias]

"Patterns"? Of course there are patterns. If there were no patterns, that would be suspicious. Do you claim to be able to look at a picture of a random number generator data and determine the quality based on that? You do realize that even perfectly random data may have patterns?

[dasmithii]

It serves mostly as a litmus test against blatant predictability. As said above, sequential lines or otherwise obvious shapes would indicate poor randomness.

I wouldn't evaluate a generator solely on the basis of a bytemap. But these visualizations are of value.