Your point about the button suggesting histogram display is also valid. That could indeed be the interpretation if the landscapes looked too much like histograms.
I like XnTriq's approach.
A silhouette of a human head might be made to work, too.
All this just points up the extraordinary difficulty in designing good icons for "technical" concepts.
That's as many hairs as I'm going to split on this topic, though.

Whatever the consensus is fine with me.