/// <summary>
/// Completely tear down a filter graph and
/// release all associated resources.
/// </summary>
protected void DestroyGraph()
{
// Derender the graph (This will stop the graph
// and release preview window. It also destroys
// half of the graph which is unnecessary but
// harmless here.) (ignore errors)
try { DerenderGraph(); }
catch { }
// Update the state after derender because it
// depends on correct status. But we also want to
// update the state as early as possible in case
// of error.
ActualGraphState = GraphState.Null;
IsPreviewRendered = false;
// Remove filters from the graph
// This should be unnecessary but the Nvidia WDM
// video driver cannot be used by this application
// again unless we remove it. Ideally, we should
// simply enumerate all the filters in the graph
// and remove them. (ignore errors)
if (VideoCompressorFilter != null)
{
GraphBuilder.RemoveFilter(VideoCompressorFilter);
}
if (VideoDeviceFilter != null)
{
GraphBuilder.RemoveFilter(VideoDeviceFilter);
}
// Cleanup
if (GraphBuilder != null)
{
Marshal.ReleaseComObject(GraphBuilder);
}
GraphBuilder = null;
if (CaptureGraphBuilder != null)
{
Marshal.ReleaseComObject(CaptureGraphBuilder);
}
CaptureGraphBuilder = null;
if (VideoDeviceFilter != null)
{
Marshal.ReleaseComObject(VideoDeviceFilter);
}
VideoDeviceFilter = null;
if (VideoCompressorFilter != null)
{
Marshal.ReleaseComObject(VideoCompressorFilter);
}
VideoCompressorFilter = null;
// These are copies of graphBuilder
MediaControl = null;
VideoWindow = null;
// For unmanaged objects we haven't released explicitly
GC.Collect();
}
/// <summary>
/// Removes all filters downstream from a filter from the graph.
/// This is called only by DerenderGraph() to remove everything
/// from the graph except the devices and compressors. The parameter
/// "removeFirstFilter" is used to keep a compressor (that should
/// be immediately downstream of the device) if one is begin used.
/// </summary>
protected void RemoveDownstream(CoreStreaming.IBaseFilter filter, bool removeFirstFilter)
{
// Get a pin enumerator off the filter
CoreStreaming.IEnumPins pinEnum;
var hr = filter.EnumPins(out pinEnum);
if (pinEnum != null)
{
pinEnum.Reset();
if ((hr == 0))
{
// Loop through each pin
var pins = new CoreStreaming.IPin[1];
int f;
do
{
// Get the next pin
hr = pinEnum.Next(1, pins, out f);
if ((hr == 0) && (pins[0] != null))
{
// Get the pin it is connected to
CoreStreaming.IPin pinTo = null;
pins[0].ConnectedTo(out pinTo);
if (pinTo != null)
{
// Is this an input pin?
var info = new CoreStreaming.PinInfo();
hr = pinTo.QueryPinInfo(out info);
if ((hr == 0) && (info.dir == CoreStreaming.PinDirection.Input))
{
// Recurse down this branch
RemoveDownstream(info.filter, true);
// Disconnect
GraphBuilder.Disconnect(pinTo);
GraphBuilder.Disconnect(pins[0]);
// Remove this filter
// but don't remove the video or audio compressors
if (info.filter != VideoCompressorFilter)
{
GraphBuilder.RemoveFilter(info.filter);
}
}
Marshal.ReleaseComObject(info.filter);
Marshal.ReleaseComObject(pinTo);
}
Marshal.ReleaseComObject(pins[0]);
}
} while (hr == 0);
Marshal.ReleaseComObject(pinEnum); pinEnum = null;
}
}
}
/// <summary>
/// Create a new filter graph and add filters (devices, compressors, misc),
/// but leave the filters unconnected. Call RenderGraph()
/// to connect the filters.
/// </summary>
protected void CreateGraph()
{
//Skip if already created
if ((int)ActualGraphState < (int)GraphState.Created)
{
// Make a new filter graph
GraphBuilder = (ExtendStreaming.IGraphBuilder)Activator.CreateInstance(Type.GetTypeFromCLSID(Uuid.Clsid.FilterGraph, true));
// Get the Capture Graph Builder
var clsid = Uuid.Clsid.CaptureGraphBuilder2;
var riid = typeof(ExtendStreaming.ICaptureGraphBuilder2).GUID;
CaptureGraphBuilder = (ExtendStreaming.ICaptureGraphBuilder2)Workaround.CreateDsInstance(ref clsid, ref riid);
// Link the CaptureGraphBuilder to the filter graph
var hr = CaptureGraphBuilder.SetFiltergraph(GraphBuilder);
if (hr < 0)
{
Marshal.ThrowExceptionForHR(hr);
}
var comType = Type.GetTypeFromCLSID(Uuid.Clsid.SampleGrabber);
if (comType == null)
{
throw new NotImplementedException(@"DirectShow SampleGrabber not installed/registered!");
}
var comObj = Activator.CreateInstance(comType);
SampGrabber = (EditStreaming.ISampleGrabber)comObj; comObj = null;
_baseGrabFlt = (CoreStreaming.IBaseFilter)SampGrabber;
var media = new CoreStreaming.AMMediaType();
// Get the video device and add it to the filter graph
if (VideoDevice != null)
{
VideoDeviceFilter = (CoreStreaming.IBaseFilter)Marshal.BindToMoniker(VideoDevice.MonikerString);
hr = GraphBuilder.AddFilter(VideoDeviceFilter, "Video Capture Device");
if (hr < 0)
{
Marshal.ThrowExceptionForHR(hr);
}
media.majorType = Uuid.MediaType.Video;
media.subType = Uuid.MediaSubType.RGB32; //RGB24;
media.formatType = Uuid.FormatType.VideoInfo;
media.temporalCompression = true; //New
hr = SampGrabber.SetMediaType(media);
if (hr < 0)
{
Marshal.ThrowExceptionForHR(hr);
}
hr = GraphBuilder.AddFilter(_baseGrabFlt, "Grabber");
if (hr < 0)
{
Marshal.ThrowExceptionForHR(hr);
}
}
// Retrieve the stream control interface for the video device
// FindInterface will also add any required filters
// (WDM devices in particular may need additional
// upstream filters to function).
// Try looking for an interleaved media type
object o;
var cat = Uuid.PinCategory.Capture;
var med = Uuid.MediaType.Interleaved;
var iid = typeof(ExtendStreaming.IAMStreamConfig).GUID;
hr = CaptureGraphBuilder.FindInterface(ref cat, ref med, VideoDeviceFilter, ref iid, out o);
if (hr != 0)
{
// If not found, try looking for a video media type
med = Uuid.MediaType.Video;
hr = CaptureGraphBuilder.FindInterface(ref cat, ref med, VideoDeviceFilter, ref iid, out o);
if (hr != 0)
{
o = null;
}
}
VideoStreamConfig = o as ExtendStreaming.IAMStreamConfig;
// Retreive the media control interface (for starting/stopping graph)
MediaControl = (ControlStreaming.IMediaControl)GraphBuilder;
// Reload any video crossbars
//if (videoSources != null) videoSources.Dispose(); videoSources = null;
_videoInfoHeader = (EditStreaming.VideoInfoHeader)Marshal.PtrToStructure(media.formatPtr, typeof(EditStreaming.VideoInfoHeader));
Marshal.FreeCoTaskMem(media.formatPtr); media.formatPtr = IntPtr.Zero;
hr = SampGrabber.SetBufferSamples(false);
if (hr == 0)
{
hr = SampGrabber.SetOneShot(false);
}
if (hr == 0)
{
hr = SampGrabber.SetCallback(null, 0);
}
if (hr < 0)
{
Marshal.ThrowExceptionForHR(hr);
}
}
// Update the state now that we are done
ActualGraphState = GraphState.Created;
}
/// <summary>
/// Completely tear down a filter graph and
/// release all associated resources.
/// </summary>
protected void DestroyGraph()
{
// Derender the graph (This will stop the graph
// and release preview window. It also destroys
// half of the graph which is unnecessary but
// harmless here.) (ignore errors)
try { DerenderGraph(); }
catch { }
// Update the state after derender because it
// depends on correct status. But we also want to
// update the state as early as possible in case
// of error.
ActualGraphState = GraphState.Null;
IsPreviewRendered = false;
// Remove filters from the graph
// This should be unnecessary but the Nvidia WDM
// video driver cannot be used by this application
// again unless we remove it. Ideally, we should
// simply enumerate all the filters in the graph
// and remove them. (ignore errors)
if (VideoCompressorFilter != null)
GraphBuilder.RemoveFilter(VideoCompressorFilter);
if (VideoDeviceFilter != null)
GraphBuilder.RemoveFilter(VideoDeviceFilter);
// Cleanup
if (GraphBuilder != null)
Marshal.ReleaseComObject(GraphBuilder); GraphBuilder = null;
if (CaptureGraphBuilder != null)
Marshal.ReleaseComObject(CaptureGraphBuilder); CaptureGraphBuilder = null;
if (VideoDeviceFilter != null)
Marshal.ReleaseComObject(VideoDeviceFilter); VideoDeviceFilter = null;
if (VideoCompressorFilter != null)
Marshal.ReleaseComObject(VideoCompressorFilter); VideoCompressorFilter = null;
// These are copies of graphBuilder
MediaControl = null;
VideoWindow = null;
// For unmanaged objects we haven't released explicitly
GC.Collect();
}
/// <summary>
/// Create a new filter graph and add filters (devices, compressors, misc),
/// but leave the filters unconnected. Call RenderGraph()
/// to connect the filters.
/// </summary>
protected void CreateGraph()
{
//Skip if already created
if ((int)ActualGraphState < (int)GraphState.Created)
{
// Make a new filter graph
GraphBuilder = (ExtendStreaming.IGraphBuilder)Activator.CreateInstance(Type.GetTypeFromCLSID(Uuid.Clsid.FilterGraph, true));
// Get the Capture Graph Builder
Guid clsid = Uuid.Clsid.CaptureGraphBuilder2;
Guid riid = typeof(ExtendStreaming.ICaptureGraphBuilder2).GUID;
CaptureGraphBuilder = (ExtendStreaming.ICaptureGraphBuilder2)Workaround.CreateDsInstance(ref clsid, ref riid);
// Link the CaptureGraphBuilder to the filter graph
int hr = CaptureGraphBuilder.SetFiltergraph(GraphBuilder);
if (hr < 0) Marshal.ThrowExceptionForHR(hr);
Type comType = Type.GetTypeFromCLSID(Uuid.Clsid.SampleGrabber);
if (comType == null)
throw new NotImplementedException(@"DirectShow SampleGrabber not installed/registered!");
object comObj = Activator.CreateInstance(comType);
SampGrabber = (EditStreaming.ISampleGrabber)comObj; comObj = null;
_baseGrabFlt = (CoreStreaming.IBaseFilter)SampGrabber;
var media = new CoreStreaming.AMMediaType();
// Get the video device and add it to the filter graph
if (VideoDevice != null)
{
VideoDeviceFilter = (CoreStreaming.IBaseFilter)Marshal.BindToMoniker(VideoDevice.MonikerString);
hr = GraphBuilder.AddFilter(VideoDeviceFilter, "Video Capture Device");
if (hr < 0) Marshal.ThrowExceptionForHR(hr);
media.majorType = Uuid.MediaType.Video;
media.subType = Uuid.MediaSubType.RGB32;//RGB24;
media.formatType = Uuid.FormatType.VideoInfo;
media.temporalCompression = true; //New
hr = SampGrabber.SetMediaType(media);
if (hr < 0)
Marshal.ThrowExceptionForHR(hr);
hr = GraphBuilder.AddFilter(_baseGrabFlt, "Grabber");
if (hr < 0) Marshal.ThrowExceptionForHR(hr);
}
// Retrieve the stream control interface for the video device
// FindInterface will also add any required filters
// (WDM devices in particular may need additional
// upstream filters to function).
// Try looking for an interleaved media type
object o;
Guid cat = Uuid.PinCategory.Capture;
Guid med = Uuid.MediaType.Interleaved;
Guid iid = typeof(ExtendStreaming.IAMStreamConfig).GUID;
hr = CaptureGraphBuilder.FindInterface(ref cat, ref med, VideoDeviceFilter, ref iid, out o);
if (hr != 0)
{
// If not found, try looking for a video media type
med = Uuid.MediaType.Video;
hr = CaptureGraphBuilder.FindInterface(
ref cat, ref med, VideoDeviceFilter, ref iid, out o);
if (hr != 0)
o = null;
}
VideoStreamConfig = o as ExtendStreaming.IAMStreamConfig;
// Retreive the media control interface (for starting/stopping graph)
MediaControl = (ControlStreaming.IMediaControl)GraphBuilder;
// Reload any video crossbars
//if (videoSources != null) videoSources.Dispose(); videoSources = null;
_videoInfoHeader = (EditStreaming.VideoInfoHeader)Marshal.PtrToStructure(media.formatPtr, typeof(EditStreaming.VideoInfoHeader));
Marshal.FreeCoTaskMem(media.formatPtr); media.formatPtr = IntPtr.Zero;
hr = SampGrabber.SetBufferSamples(false);
if (hr == 0)
hr = SampGrabber.SetOneShot(false);
if (hr == 0)
hr = SampGrabber.SetCallback(null, 0);
if (hr < 0)
Marshal.ThrowExceptionForHR(hr);
}
// Update the state now that we are done
ActualGraphState = GraphState.Created;
}
