By default, video plays back based upon the timestamp for each frame,
and buffers the frames as needed to ensure that they play back at the
expected timing.
However, this can add some minor additional delay to the video, and may
not be ideal for certain devices such as webcams and generally any
device that has minimal latency. However, because those are the only
type of devices that typically have drivers, there's no real need to
have it on by default.
This adds an option to use buffering, and leaves it off by default.
Closes pull request #384
(message added by jim)