That bug has been opened on https://launchpad.net/distros/ubuntu/+source/control-center/+bug/47170

"In the About me dialog, I can't set a picture : if I click on the default picture / picture frame, I can select a file, but it isn't displayed in the window after that. Tried with PNG and JPG files.
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> I cannot confirm this. I tried with a random PNG file and it worked. Can you please attach a file that causes the problem? Thanks.
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http://librarian.launchpad.net/2991820/test.png
OK, I attached this (you won't know that the file will remain on that site for as long as this bug is open :-). Generally, to attach files on LP you click the "Add attachment" link on your left.
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Also, I've just made a few more tests : when the picture has bigger dimensions, it gets displayed in the frame, but at a tiny size (I resized my test picture at 100 x 100 : no change, then at 500 x 500 and it gets displayed).
But when I quit and relaunch the "About me" application, the user picture is empty again.

I've also tried with the picture that I use as desktop background (2580 x 1932 jpeg file) and I can use it as user picture (although it is also displayed as a tiny thumbnail in the frame). But this big jpeg file is kept as user picture when I quit / relaunch "About me".

You can see this behaviour there : http://abel.thorne.free.fr/vrac/capture.png
"