New Post: Changing Webcam resolution

[ComImport, System.Security.SuppressUnmanagedCodeSecurity,
Guid("C6E13340-30AC-11d0-A18C-00A0C9118956"),
InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]internalinterface IAMStreamConfig
    {
        [PreserveSig]int SetFormat([In, MarshalAs(UnmanagedType.LPStruct)] AMMediaType pmt);

        [PreserveSig]
        int GetFormat([Out] out AMMediaType pmt);

        [PreserveSig]
        int GetNumberOfCapabilities(outint piCount, outint piSize);

        [PreserveSig]
        int GetStreamCaps(
            [In] int iIndex,
            [Out] out AMMediaType ppmt,
            [In] VideoStreamConfigCaps pSCC
            );
    }

    [StructLayout(LayoutKind.Sequential)]
    publicclass VideoStreamConfigCaps
    {public Guid guid;public AnalogVideoStandard VideoStandard;public Size InputSize;public Size MinCroppingSize;public Size MaxCroppingSize;publicint CropGranularityX;publicint CropGranularityY;publicint CropAlignX;publicint CropAlignY;public Size MinOutputSize;public Size MaxOutputSize;publicint OutputGranularityX;publicint OutputGranularityY;publicint StretchTapsX;publicint StretchTapsY;publicint ShrinkTapsX;publicint ShrinkTapsY;publiclong MinFrameInterval;publiclong MaxFrameInterval;publicint MinBitsPerSecond;publicint MaxBitsPerSecond;
    }
    [Flags]publicenum AnalogVideoStandard
    {
        None = 0x00000000,
        NTSC_M = 0x00000001,
        NTSC_M_J = 0x00000002,
        NTSC_433 = 0x00000004,
        PAL_B = 0x00000010,
        PAL_D = 0x00000020,
        PAL_G = 0x00000040,
        PAL_H = 0x00000080,
        PAL_I = 0x00000100,
        PAL_M = 0x00000200,
        PAL_N = 0x00000400,
        PAL_60 = 0x00000800,
        SECAM_B = 0x00001000,
        SECAM_D = 0x00002000,
        SECAM_G = 0x00004000,
        SECAM_H = 0x00008000,
        SECAM_K = 0x00010000,
        SECAM_K1 = 0x00020000,
        SECAM_L = 0x00040000,
        SECAM_L1 = 0x00080000,
        PAL_N_COMBO = 0x00100000,

        NTSCMask = 0x00000007,
        PALMask = 0x00100FF0,
        SECAMMask = 0x000FF000
    }

///<summary>/// Worker thread that captures the images///</summary>privatevoid RunWorker()
        {try
            {// Create the main graph
                _graph = Activator.CreateInstance(Type.GetTypeFromCLSID(FilterGraph)) as IGraphBuilder;// Create the webcam source
                _sourceObject = FilterInfo.CreateFilter(_monikerString);// Create the grabber
                _grabber = Activator.CreateInstance(Type.GetTypeFromCLSID(SampleGrabber)) as ISampleGrabber;
                _grabberObject = _grabber as IBaseFilter;// Add the source and grabber to the main graph
                _graph.AddFilter(_sourceObject, "source");
                _graph.AddFilter(_grabberObject, "grabber");using (AMMediaType mediaType = new AMMediaType())
                {
                    mediaType.MajorType = MediaTypes.Video;
                    mediaType.SubType = MediaSubTypes.RGB32;
                    _grabber.SetMediaType(mediaType);

                    IEnumPins _enumPin;
                    _sourceObject.EnumPins(out _enumPin);
                    IPin[] _IPP = new IPin[3];int pt = -1;
                    _enumPin.Next(3, _IPP, out pt);

                    IAMStreamConfig st = (IAMStreamConfig)_IPP[0];

                    AMMediaType med = new AMMediaType();
                    st.GetFormat(out med);
                    VideoInfoHeader head = (VideoInfoHeader)Marshal.PtrToStructure(med.FormatPtr, typeof(VideoInfoHeader));//head.BmiHeader.Width = 1280;//head.BmiHeader.Height = 720;

                    head.BmiHeader.Width = 1600;
                    head.BmiHeader.Height = 900;

                    Marshal.StructureToPtr(head, med.FormatPtr, false);
                    st.SetFormat(med);if (_graph.Connect(_sourceObject.GetPin(PinDirection.Output, 0), _grabberObject.GetPin(PinDirection.Input, 0)) >= 0)
                    {if (_grabber.GetConnectedMediaType(mediaType) == 0)
                        {// During startup, this code can be too fast, so try at least 3 timesint retryCount = 0;bool succeeded = false;while ((retryCount < 3) && !succeeded)
                            {// Tried again
                                retryCount++;try
                                {// Retrieve the grabber information
                                    VideoInfoHeader header = (VideoInfoHeader)Marshal.PtrToStructure(mediaType.FormatPtr, typeof(VideoInfoHeader));
                                    _capGrabber.Width = header.BmiHeader.Width;
                                    _capGrabber.Height = header.BmiHeader.Height;
                                    logger.Info("Camera Resolution is set to " + header.BmiHeader.Height + " x " + header.BmiHeader.Width);// Succeeded
                                    succeeded = true;
                                }catch (Exception retryException)
                                {// Trace
                                    Trace.TraceInformation("Failed to retrieve the grabber information, tried {0} time(s)", retryCount);
                                    logger.Fatal("Failed to retrieve the grabber information: " + retryException.Message);// Sleep
                                    Thread.Sleep(50);
                                }
                            }
                        }
                    }
                    _graph.Render(_grabberObject.GetPin(PinDirection.Output, 0));
                    _grabber.SetBufferSamples(false);
                    _grabber.SetOneShot(false);
                    _grabber.SetCallback(_capGrabber, 1);// Get the video window
                    IVideoWindow wnd = (IVideoWindow)_graph;
                    wnd.put_AutoShow(false);
                    wnd = null;// Create the control and run
                    _control = (IMediaControl)_graph;
                    _control.Run();// Wait for the stop signal// while (!_stopSignal.WaitOne(10, true))//{//Thread.Sleep(10);//}
                    _stopSignal.WaitOne();// Stop when ready
                    _control.StopWhenReady();
                }
            }catch (Exception ex)
            {// Trace
                Trace.WriteLine(ex);
            }finally
            {// Clean up
                Release();
            }
        }