AForge.Video.DirectShow.FileVideoSource.WorkerThread C# (CSharp) Method

        private void WorkerThread( )
        {
            ReasonToFinishPlaying reasonToStop = ReasonToFinishPlaying.StoppedByUser;

            // grabber
            Grabber grabber = new Grabber( this );

            // objects
            object graphObject = null;
            object grabberObject = null;

            // interfaces
            IGraphBuilder       graph = null;
            IBaseFilter         sourceBase = null;
            IBaseFilter         grabberBase = null;
            ISampleGrabber      sampleGrabber = null;
            IMediaControl       mediaControl = null;

            IMediaEventEx       mediaEvent = null;

            try
            {
                // get type for filter graph
                Type type = Type.GetTypeFromCLSID( Clsid.FilterGraph );
                if ( type == null )
                    throw new ApplicationException( "Failed creating filter graph" );

                // create filter graph
                graphObject = Activator.CreateInstance( type );
                graph = (IGraphBuilder) graphObject;

                // create source device's object
                graph.AddSourceFilter( fileName, "source", out sourceBase );
                if ( sourceBase == null )
                    throw new ApplicationException( "Failed creating source filter" );

                // get type for sample grabber
                type = Type.GetTypeFromCLSID( Clsid.SampleGrabber );
                if ( type == null )
                    throw new ApplicationException( "Failed creating sample grabber" );

                // create sample grabber
                grabberObject = Activator.CreateInstance( type );
                sampleGrabber = (ISampleGrabber) grabberObject;
                grabberBase = (IBaseFilter) grabberObject;

                // add grabber filters to graph
                graph.AddFilter( grabberBase, "grabber" );

                // set media type
                AMMediaType mediaType = new AMMediaType( );
                mediaType.MajorType = MediaType.Video;
                mediaType.SubType = MediaSubType.RGB24;
                sampleGrabber.SetMediaType( mediaType );

                // connect pins
                int pinToTry = 0;

                IPin inPin = Tools.GetInPin( grabberBase, 0 );
                IPin outPin = null;

                // find output pin acceptable by sample grabber
                while ( true )
                {
                    outPin = Tools.GetOutPin( sourceBase, pinToTry );

                    if ( outPin == null )
                    {
                        Marshal.ReleaseComObject( inPin );
                        throw new ApplicationException( "Did not find acceptable output video pin in the given source" );
                    }

                    if ( graph.Connect( outPin, inPin ) < 0 )
                    {
                        Marshal.ReleaseComObject( outPin );
                        outPin = null;
                        pinToTry++;
                    }
                    else
                    {
                        break;
                    }
                }

                Marshal.ReleaseComObject( outPin );
                Marshal.ReleaseComObject( inPin );

                // get media type
                if ( sampleGrabber.GetConnectedMediaType( mediaType ) == 0 )
                {
                    VideoInfoHeader vih = (VideoInfoHeader) Marshal.PtrToStructure( mediaType.FormatPtr, typeof( VideoInfoHeader ) );

                    grabber.Width = vih.BmiHeader.Width;
                    grabber.Height = vih.BmiHeader.Height;
                    mediaType.Dispose( );
                }

                // let's do rendering, if we don't need to prevent freezing
                if ( !preventFreezing )
                {
                    // render pin
                    graph.Render( Tools.GetOutPin( grabberBase, 0 ) );

                    // configure video window
                    IVideoWindow window = (IVideoWindow) graphObject;
                    window.put_AutoShow( false );
                    window = null;
                }

                // configure sample grabber
                sampleGrabber.SetBufferSamples( false );
                sampleGrabber.SetOneShot( false );
                sampleGrabber.SetCallback( grabber, 1 );

                // disable clock, if someone requested it
                if ( !referenceClockEnabled )
                {
                    IMediaFilter mediaFilter = (IMediaFilter) graphObject;
                    mediaFilter.SetSyncSource( null );
                }

                // get media control
                mediaControl = (IMediaControl) graphObject;

                // get media events' interface
                mediaEvent = (IMediaEventEx) graphObject;
                IntPtr p1, p2;
                DsEvCode code;

                // run
                mediaControl.Run( );

                do
                {
                    if ( mediaEvent != null )
                    {
                        if ( mediaEvent.GetEvent( out code, out p1, out p2, 0 ) >= 0 )
                        {
                            mediaEvent.FreeEventParams( code, p1, p2 );

                            if ( code == DsEvCode.Complete )
                            {
                                reasonToStop = ReasonToFinishPlaying.EndOfStreamReached;
                                break;
                            }
                        }
                    }
                }
                while ( !stopEvent.WaitOne( 100, false ) );

                mediaControl.Stop( );
            }
            catch ( Exception exception )
            {
                // provide information to clients
                if ( VideoSourceError != null )
                {
                    VideoSourceError( this, new VideoSourceErrorEventArgs( exception.Message ) );
                }
            }
            finally
            {
                // release all objects
                graph           = null;
                grabberBase     = null;
                sampleGrabber   = null;
                mediaControl    = null;
                mediaEvent      = null;

                if ( graphObject != null )
                {
                    Marshal.ReleaseComObject( graphObject );
                    graphObject = null;
                }
                if ( sourceBase != null )
                {
                    Marshal.ReleaseComObject( sourceBase );
                    sourceBase = null;
                }
                if ( grabberObject != null )
                {
                    Marshal.ReleaseComObject( grabberObject );
                    grabberObject = null;
                }
            }

            if ( PlayingFinished != null )
            {
                PlayingFinished( this, reasonToStop );
            }
        }