Timestamp convertTimeToStreamPos(const Timestamp &where, int rate, bool isStereo) {
Timestamp result(where.convertToFramerate(rate * (isStereo ? 2 : 1)));
// When the Stream is a stereo stream, we have to assure
// that the sample position is an even number.
if (isStereo && (result.totalNumberOfFrames() & 1))
result = result.addFrames(-1); // We cut off one sample here.
// Since Timestamp allows sub-frame-precision it might lead to odd behaviors
// when we would just return result.
//
// An example is when converting the timestamp 500ms to a 11025 Hz based
// stream. It would have an internal frame counter of 5512.5. Now when
// doing calculations at frame precision, this might lead to unexpected
// results: The frame difference between a timestamp 1000ms and the above
// mentioned timestamp (both with 11025 as framerate) would be 5512,
// instead of 5513, which is what a frame-precision based code would expect.
//
// By creating a new Timestamp with the given parameters, we create a
// Timestamp with frame-precision, which just drops a sub-frame-precision
// information (i.e. rounds down).
return Timestamp(result.secs(), result.numberOfFrames(), result.framerate());
}
