private void SeekToTime(double seconds, SeekModes seekMode)
{
if ((_pendingFrame != null) && (_pendingFrame.Fields != null))
{
if (seekMode == SeekModes.Accurate)
{
for (int fieldIndex = 0; fieldIndex < _pendingFrame.Fields.Length; fieldIndex++)
{
var field = _pendingFrame.Fields[fieldIndex];
if ((field.Seconds == seconds))
{
_pendingFrame.CurrentIndex = fieldIndex;
return;
}
}
}
else
{
if (_pendingFrame.IsKeyFrame)
{
return;
}
}
}
long pts = (long)(seconds * _videoCodecContext.pkt_timebase.den / (double)_videoCodecContext.pkt_timebase.num);
SeekToPTS(pts, seekMode);
}
private void SeekToPTS(long pts, SeekModes seekMode)
{
if (seekMode == SeekModes.PreviousKeyFrame)
{
SeekToPTS(pts, true);
}
else if (seekMode == SeekModes.NextKeyFrame)
{
SeekToPTS(pts, false);
while (!_pendingFrame.IsKeyFrame)
{
var previousFrame = _pendingFrame;
_pendingFrame = ReadVideoFrame();
if (_pendingFrame == null)
{
_pendingFrame = previousFrame;
return;
}
DisposeFrame(ref previousFrame);
}
}
else
{
SeekToPTS(pts, false);
}
}
public FrameField GetVideoFrameField(int fieldNumber, SeekModes seekMode = SeekModes.Accurate)
{
FrameField frame = null;
SeekToField(fieldNumber, seekMode);
if (_pendingFrame != null)
{
frame = _pendingFrame.Fields[_pendingFrame.CurrentIndex];
//frame.Image.Save(@"D:\temp\image-" + frame.FrameNumber.ToString("00000") + ".png", System.Drawing.Imaging.ImageFormat.Png);
}
_pendingFrame.CurrentIndex++;
if (_pendingFrame.CurrentIndex >= _pendingFrame.Fields.Length)
{
_pendingFrame = ReadVideoFrame();
}
return(frame);
}
private void SeekToField(int fieldNumber, SeekModes seekMode)
{
if ((_pendingFrame != null) && (_pendingFrame.Fields != null))
{
if ((seekMode == SeekModes.Accurate) || (_pendingFrame.IsKeyFrame))
{
for (int fieldIndex = 0; fieldIndex < _pendingFrame.Fields.Length; fieldIndex++)
{
var field = _pendingFrame.Fields[fieldIndex];
if ((field.FieldNumber == fieldNumber))
{
_pendingFrame.CurrentIndex = fieldIndex;
return;
}
}
}
}
long pts = PTSPerField * fieldNumber;
SeekToPTS(pts, seekMode);
}
