Before I start, let me say that CarTunes is awesome. The color matching feature works great 95% of the time. If you make no changes to it whatsoever, I will continue to enjoy using CarTunes and recommend it to others.
That being said, there are a few times where CarTunes doesn't seem to pick a color that I would expect, and I think I have identified what is going on in those circumstances. Here's what I've found:
1. Brightening Colors
Sometimes, the selection color is 'boosted'. I think that causes some issues, and it may look better if the color remained 'dull', as it will better match the image.
I don't see any yellow in that image. There is a tan tint to some of the keys, but nothing as bold as that yellow.
This is a similar color boost. I'd rather see a duller blue.
2. Flesh Tones
There are times when the image is basically black and white, and the only color is skin. However, picking a single color out of the complexities of skin can look strange. Here are examples, with black and white people:
3. Other
I'm really not sure what happened with these, but here we go:
The image is black and white, the bar is grey. White would look better.
There's nothing close to grey in this image, I wonder why it didn't pick red.
I never noticed that there was green in this picture until I used CarTunes.
So, that's it so far. I hope that this is helpful to you. I love your app, and I just want to do what I can to help make it as good as possible.