Filters automatically selected

Filters automatically selected
When invoking StartPreview, StartRecording, OpenPlayer or StartReencoding, each filter automatically selected when constructing the graph is reported by the OnFilterSelected event.

From this event it is possible:
- to see which filters are automatically selected,
- to reject a given filter by enabling the RejectFilter parameter, to prevent this filter from being used.

Note that when rejecting a filter, this assumes that other compatible filters are installed on the platform and will be selected instead, otherwise the construction of the graph will probably fail or be incomplete
(e.g. if the capture device has both an audio stream and a video stream, and both streams must be recorded or rendered, either the video stream or the audio stream could be missing)