/// <summary>
/// Calculates dropped frame statistics based on the difference in
/// timestamps between two consecutive headers.
/// </summary>
/// <param name="stream">
/// The KStudioSeekableEventStream object of the video stream
/// </param>
/// <param name="frameTime">The number of milliseconds per frame</param>
/// <returns>
/// FrameAnalysis object with collected frame statistics.
/// </returns>
public override FrameAnalysis CountDroppedFrames()
{
double prevFrameTime = 0;
double cumulativeTime = 0;
int eventIndex = 0;
FrameAnalysis result = new FrameAnalysis();
KStudioSeekableEventStream stream = (KStudioSeekableEventStream)_stream;
prevFrameTime = stream.StartRelativeTime.TotalMilliseconds;
foreach (KStudioEventHeader header in stream.EventHeaders)
{
double currentFrameTime = header.RelativeTime.TotalMilliseconds;
double deltaTime = currentFrameTime - prevFrameTime;
cumulativeTime += deltaTime - FrameTime;
result.FrameCount++;
result.FrameMap.Add(eventIndex);
while (cumulativeTime > FrameTime)
{
result.DroppedFrames++;
cumulativeTime -= FrameTime;
result.FrameMap.Add(eventIndex);
result.DroppedIndices.Add(result.FrameCount++);
}
eventIndex++;
prevFrameTime = currentFrameTime;
}
return(result);
}
/// <summary>
/// Calculates dropped frame statistics based on the difference in
/// timestamps between two consecutive headers.
/// </summary>
/// <param name="stream">
/// The KStudioSeekableEventStream object of the audio stream
/// </param>
/// <param name="frameTime">
/// The number of milliseconds per audio audio frame. This is not
/// necessarily the time per event header as multiple audio samples can
/// be stored in a single event.
/// </param>
/// <returns>
/// FrameAnalysis object with collected frame statistics.
/// </returns>
public override FrameAnalysis CountDroppedFrames()
{
double prevFrameTime = 0;
double cumulativeTime = 0;
int lastGoodEvent = 0;
int eventIndex = 0;
int eventFrameSize = 14432;
FrameAnalysis result = new FrameAnalysis();
KStudioSeekableEventStream stream = (KStudioSeekableEventStream)_stream;
foreach (KStudioEventHeader header in stream.EventHeaders)
{
double currentFrameTime = header.RelativeTime.TotalMilliseconds;
double deltaTime = currentFrameTime - prevFrameTime;
double missedTime = 0;
int j = 0;
// Determine if there are missed frames.
do
{
j += eventFrameSize - 16;
missedTime += FrameTime;
} while (j <= (int)header.EventDataSize);
missedTime = deltaTime - missedTime;
cumulativeTime += missedTime;
if (cumulativeTime > FrameTime)
{
while (cumulativeTime > FrameTime)
{
cumulativeTime -= FrameTime;
result.DroppedFrames++;
result.FrameMap.Add(lastGoodEvent);
result.DroppedIndices.Add(result.FrameCount++);
}
}
else
{
lastGoodEvent = eventIndex;
result.FrameMap.Add(lastGoodEvent);
result.FrameCount++;
}
eventIndex++;
prevFrameTime = currentFrameTime;
}
return(result);
}
public KinectColor(KStudioEventStream stream) : base(stream)
{
_frameAnalysis = CountDroppedFrames();
}
