Theoretically, it should be possible for camera to save photographs temporarily to non-encrypted filesystem, and then, when you press photo-gallery button within camera app, request from you the lockcode to get access to your disk, and incidentally use the access to both transfer photographs from temporary location to proper directory, and to show you the photo gallery.

It does sound overly complicated...

[Edit]
So, "Enter lock code" happens even for non-encrypted filesystem (for me, too)... Not sure how to bypass that. Also, it should be by-passable to call emergency numbers, too, not only to take photographs and-or record audio-and-or-video. Do incoming calls bypass the "Enter lock code" dialog? I think so (need to check). If yes, then how?
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