Some video-files have their metadata as -90 instead of 90. This PR handles correct aspect-ratio and rotation when taking snapshots.
The sample video provided in the PR is my own recording. A bit too big maybe? I couldn't find any command to set the metadata to `-90` on existing video. Would be happy to get it working on already existing test-data to reduce size.
Fixes#509
* Added ability to retrieve bit depth from media streams for lossless encodings
* Shortened sample AIFF file used in tests
Former-commit-id: db7e1e4995
