The frame is the interleaved set of one sample for each channel. Add some docs and some methods that make working with samples a bit more convenient. Adjusted QAudioBuffer to use these helper functions and terminology. Change-Id: I96db48e659561972d6de2aa19893d29f9a828cd3 Reviewed-by: Dmytro Poplavskiy <dmytro.poplavskiy@nokia.com>