Adrien Béraud authored Feb 17, 2016 and Guillaume Roguez committed Feb 17, 2016

* use default settings if no preference exists
* logic requires unformated parameters (added related methods)
* current logic: largest resolution <= 720P, framerate >= 10 FPS
* support new pixel format
* report pixel format to libav/ffmpeg for decoding

Tuleap: #294
Change-Id: Ia9b61814b49e7057ae4eb5fef9d0b814706cafff