Thanks for the PR @ptweir ! Could you add an example in https://github.com/pyqtgraph/pyqtgraph/tree/develop/examples that demonstrates this usage? Seeing it in action would help evaluate the PR

Hi @ericdill thanks for the suggestion. Let me know how to improve the example and/or changes. (I've included an example script based on the ImageView.py example script.)

It turns out ImageView has sort of independently evolved to support ROI average curves for each color channel (4a4a738), including stacked color images, so this example just works (once #1291 is merged). Making a note here that we should cherry-pick f5c4eee because that's a pretty cool example that really demonstrates what's going on.

@ixjlyons just saw your comment (why am I so bad at this); you suggesting either updating this PR (or creating a new PR) with just f5c4eee and things will "just work"?

@ptweir sorry this PR has sat idle for so long, we've had quite the PR back-log which I've made a priority to go through.

@j9ac9k yeah the example works with the current state of ImageView without further modification. My suggestion was to just grab this example script then add it to the example app. I started doing it and waffled on it because I'm not sure it makes sense to have both examples/ImageView.py and this one. Maybe they should just be merged.

I took @ixjlyons' thought and ran with it; this PR has a funner example than the original, so I say we just use the example here. I'm closing this PR so I can just merge that example file change.

[ Edited to have fewer ambiguous pronouns ]