// assumption: this can ONLY be called when we know the next box is a fragment...
private void ScanForAudioOrVideo()
{
long pos = boxReader.BaseStream.Position;
do
{
long fragPos = boxReader.BaseStream.Position;
Fragment frag = new Fragment();
int trakID = (int)frag.GetMP4TrackID(boxReader);
if (GetFragmentHandlerType(trakID) == _handlerType)
{
if (_handlerType.Equals("soun"))
{
nextAudioFragPosition = fragPos;
audioTrackID = trakID;
}
else if (_handlerType.Equals("vide"))
{
nextVideoFragPosition = fragPos;
videoTrackID = trakID;
}
break;
}
} while (this.boxReader.PeekNextBoxType() == BoxTypes.MovieFragment);
boxReader.BaseStream.Position = pos;
audiovideoScanCompleted = true;
}
private Fragment GetNextVideoFrag()
{
if (nextVideoFragPosition < 0) return (null); // there are no more!!
boxReader.BaseStream.Position = nextVideoFragPosition;
// we know where at least the next frag is as we prepared this prior to the call of this function...
Fragment answer = new Fragment(GetTimeScale(videoTrackID), GetPayloadType(videoTrackID), runningTimeIn100NanoSecs, runningSliceIndex);
answer.Read(boxReader);
runningTimeIn100NanoSecs += (ulong)TimeArithmetic.ConvertToStandardUnit(answer.TimeScale, (decimal)answer.Duration);
runningSliceIndex += answer.Length;
nextVideoFragPosition = -1;
while (this.boxReader.PeekNextBoxType() == BoxTypes.MovieFragment)
{
long fragPos = boxReader.BaseStream.Position;
Fragment tmp = new Fragment();
int trakID = (int)tmp.GetMP4TrackID(boxReader);
if (GetFragmentHandlerType(trakID) == "vide")
{
nextVideoFragPosition = fragPos;
break;
}
}
return (answer);
}
