void mTickTimer_Tick(object sender, EventArgs e)
{
if (mPresentationClock == null)
{
return;
}
if (mMediaDuration == 0)
{
return;
}
if (mIsSeek)
{
return;
}
long lClockTime = 0;
long lSystemTime = 0;
mPresentationClock.GetCorrelatedTime(0, out lClockTime, out lSystemTime);
mSlider.Value = ((double)((double)lClockTime / (double)mMediaDuration)) * mSlider.Maximum;
}
/// <summary>
/// Retrieves the last clock time that was correlated with system time.
/// </summary>
/// <param name="clock">A valid IMFClock instance.</param>
/// <param name="clockTime">Receives the last known clock time, in units of the clock's frequency.</param>
/// <param name="systemTime">Receives the system time that corresponds to the clock time.</param>
/// <returns>If this function succeeds, it returns the S_OK member. Otherwise, it returns another HResult's member that describe the error.</returns>
public static HResult GetCorrelatedTime(this IMFClock clock, out long clockTime, out TimeSpan systemTime)
{
if (clock == null)
{
throw new ArgumentNullException("clock");
}
long tmp;
HResult hr = clock.GetCorrelatedTime(0, out clockTime, out tmp);
systemTime = hr.Succeeded() ? TimeSpan.FromTicks(tmp) : default(TimeSpan);
return(hr);
}
/// <summary>
/// Polls the graph for various data about the media that is playing
/// </summary>
protected override void OnTimerTick()
{
/* Polls the current position */
if (pClock != null)
{
long sysTime = 0;
long cTime = 0;
pClock.GetCorrelatedTime(0, out cTime, out sysTime);
if (cTime != m_currentPosition)
{
m_currentPosition = cTime;
InvokeMediaPositionChanged(null);
}
}
base.OnTimerTick();
}
protected bool IsSampleTimePassed(IMFClock pClock, IMFSample pSample)
{
Debug.Assert(pClock != null);
Debug.Assert(pSample != null);
if (pSample == null || pClock == null)
{
throw new COMException("IsSampleTimePassed", E_Pointer);
}
int hr;
bool bRet = false;
long hnsTimeNow = 0;
long hnsSystemTime = 0;
long hnsSampleStart = 0;
long hnsSampleDuration = 0;
// The sample might lack a time-stamp or a duration, and the
// clock might not report a time.
try
{
hr = pClock.GetCorrelatedTime(0, out hnsTimeNow, out hnsSystemTime);
MFError.ThrowExceptionForHR(hr);
hr = pSample.GetSampleTime(out hnsSampleStart);
MFError.ThrowExceptionForHR(hr);
hr = pSample.GetSampleDuration(out hnsSampleDuration);
MFError.ThrowExceptionForHR(hr);
if (hnsSampleStart + hnsSampleDuration < hnsTimeNow)
{
bRet = true;
}
}
catch { }
return bRet;
}
public bool ProcessSample(IMFSample pSample, out int plNextSleep)
{
HResult hr;
long hnsPresentationTime = 0;
long hnsTimeNow = 0;
long hnsSystemTime = 0;
bool bPresentNow = true;
plNextSleep = 0;
if (m_pClock != null)
{
// Get the sample's time stamp. It is valid for a sample to
// have no time stamp.
try
{
hr = pSample.GetSampleTime(out hnsPresentationTime);
MFError.ThrowExceptionForHR(hr);
// Get the clock time. (But if the sample does not have a time stamp,
// we don't need the clock time.)
hr = m_pClock.GetCorrelatedTime(0, out hnsTimeNow, out hnsSystemTime);
MFError.ThrowExceptionForHR(hr);
}
catch { }
// Calculate the time until the sample's presentation time.
// A negative value means the sample is late.
long hnsDelta = hnsPresentationTime - hnsTimeNow;
if (m_fRate < 0)
{
// For reverse playback, the clock runs backward. Therefore the delta is reversed.
hnsDelta = -hnsDelta;
}
if (hnsDelta < -m_PerFrame_1_4th)
{
// This sample is late.
bPresentNow = true;
}
else if (hnsDelta > (3 * m_PerFrame_1_4th))
{
// This sample is still too early. Go to sleep.
plNextSleep = Utils.MFTimeToMsec(hnsDelta - (3 * m_PerFrame_1_4th));
// Adjust the sleep time for the clock rate. (The presentation clock runs
// at m_fRate, but sleeping uses the system clock.)
plNextSleep = (int)(plNextSleep / Math.Abs(m_fRate));
// Don't present yet.
bPresentNow = false;
}
}
if (bPresentNow)
{
m_pCB.PresentSample(pSample, hnsPresentationTime);
// pSample released by caller along with DeQueue
}
return(bPresentNow);
}
