Edit: I was just thinking a little more about what you asked and I think it has more to do with the other caller's info. I have a friend who calls me and his silhouette is always small but still other folks call me and their pic fills my screen. Is it always small when people call you?
I was already using the dark silhouettes from the link you posted. Tried the other ones and still couldn't change the in call photo like in your screen shot. No biggie. I just liked the way the larger pic looked.
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