private void lButton_Click(object sender, RoutedEventArgs e)
        {
            var lButton = (Button)sender;

            do
            {
                if (mSourceControl == null)
                {
                    return;
                }

                if (mISessions == null)
                {
                    break;
                }

                if (lButton.Tag == null)
                {
                    break;
                }

                int lIndex = (int)lButton.Tag;

                if (lButton.Content == "Stop")
                {
                    if (mISessions.ContainsKey(lIndex))
                    {
                        mISessions[lIndex].closeSession();

                        mISessions.Remove(lIndex);

                        lButton.Content = "Start";
                    }

                    break;
                }

                ICaptureProcessor lICaptureProcessor = null;

                try
                {
                    lICaptureProcessor = IPCameraMJPEGCaptureProcessor.createCaptureProcessor(URLs[lIndex % 2]);
                }
                catch (System.Exception exc)
                {
                    MessageBox.Show(exc.Message);

                    return;
                }

                if (lICaptureProcessor == null)
                {
                    return;
                }

                object lMediaSource = null;

                mSourceControl.createSourceFromCaptureProcessor(
                    lICaptureProcessor,
                    out lMediaSource);

                if (lMediaSource == null)
                {
                    return;
                }



                object lPtrSourceNode;

                var lSourceControl = mCaptureManager.createSourceControl();

                if (lSourceControl == null)
                {
                    return;
                }

                lSourceControl.createSourceNodeFromExternalSourceWithDownStreamConnection(
                    lMediaSource,
                    0,
                    0,
                    mEVROutputNodes[lIndex],
                    out lPtrSourceNode);


                List <object> lSourceMediaNodeList = new List <object>();

                lSourceMediaNodeList.Add(lPtrSourceNode);

                var lSessionControl = mCaptureManager.createSessionControl();

                if (lSessionControl == null)
                {
                    return;
                }

                var lISession = lSessionControl.createSession(
                    lSourceMediaNodeList.ToArray());

                if (lISession == null)
                {
                    return;
                }


                lISession.registerUpdateStateDelegate(UpdateStateDelegate);

                lISession.startSession(0, Guid.Empty);

                mISessions[lIndex] = lISession;

                lButton.Content = "Stop";
            } while (false);
        }
        static public ICaptureProcessor createCaptureProcessor(string aURL)
        {
            string lPresentationDescriptor = "<?xml version='1.0' encoding='UTF-8'?>" +
                                             "<PresentationDescriptor StreamCount='1'>" +
                                             "<PresentationDescriptor.Attributes Title='Attributes of Presentation'>" +
                                             "<Attribute Name='MF_DEVSOURCE_ATTRIBUTE_SOURCE_TYPE_VIDCAP_SYMBOLIC_LINK' GUID='{58F0AAD8-22BF-4F8A-BB3D-D2C4978C6E2F}' Title='The symbolic link for a video capture driver.' Description='Contains the unique symbolic link for a video capture driver.'>" +
                                             "<SingleValue Value='MJPEGCaptureProcessor' />" +
                                             "</Attribute>" +
                                             "<Attribute Name='MF_DEVSOURCE_ATTRIBUTE_FRIENDLY_NAME' GUID='{60D0E559-52F8-4FA2-BBCE-ACDB34A8EC01}' Title='The display name for a device.' Description='The display name is a human-readable string, suitable for display in a user interface.'>" +
                                             "<SingleValue Value='MJPEG Capture Processor' />" +
                                             "</Attribute>" +
                                             "</PresentationDescriptor.Attributes>" +
                                             "<StreamDescriptor Index='0' MajorType='MFMediaType_Video' MajorTypeGUID='{73646976-0000-0010-8000-00AA00389B71}'>" +
                                             "<MediaTypes TypeCount='1'>" +
                                             "<MediaType Index='0'>" +
                                             "<MediaTypeItem Name='MF_MT_FRAME_SIZE' GUID='{1652C33D-D6B2-4012-B834-72030849A37D}' Title='Width and height of the video frame.' Description='Width and height of a video frame, in pixels.'>" +
                                             "<Value.ValueParts>" +
                                             "<ValuePart Title='Width' Value='Temp_Width' />" +
                                             "<ValuePart Title='Height' Value='Temp_Height' />" +
                                             "</Value.ValueParts>" +
                                             "</MediaTypeItem>" +
                                             "<MediaTypeItem Name='MF_MT_AVG_BITRATE' GUID='{20332624-FB0D-4D9E-BD0D-CBF6786C102E}' Title='Approximate data rate of the video stream.' Description='Approximate data rate of the video stream, in bits per second, for a video media type.'>" +
                                             "<SingleValue  Value='33570816' />" +
                                             "</MediaTypeItem>" +
                                             "<MediaTypeItem Name='MF_MT_MAJOR_TYPE' GUID='{48EBA18E-F8C9-4687-BF11-0A74C9F96A8F}' Title='Major type GUID for a media type.' Description='The major type defines the overall category of the media data.'>" +
                                             "<SingleValue Value='MFMediaType_Video' GUID='{73646976-0000-0010-8000-00AA00389B71}' />" +
                                             "</MediaTypeItem>" +
                                             //"<MediaTypeItem Name='MF_MT_DEFAULT_STRIDE' GUID='{644B4E48-1E02-4516-B0EB-C01CA9D49AC6}' Title='Default surface stride.' Description='Default surface stride, for an uncompressed video media type. Stride is the number of bytes needed to go from one row of pixels to the next.'>" +
                                             //    "<SingleValue Value='Temp_Stride' />" +
                                             //"</MediaTypeItem>" +
                                             "<MediaTypeItem Name='MF_MT_FIXED_SIZE_SAMPLES' GUID='{B8EBEFAF-B718-4E04-B0A9-116775E3321B}' Title='The fixed size of samples in stream.' Description='Specifies for a media type whether the samples have a fixed size.'>" +
                                             "<SingleValue Value='False' />" +
                                             "</MediaTypeItem>" +
                                             "<MediaTypeItem Name='MF_MT_FRAME_RATE' GUID='{C459A2E8-3D2C-4E44-B132-FEE5156C7BB0}' Title='Frame rate.' Description='Frame rate of a video media type, in frames per second.'>" +
                                             "<RatioValue Value='1.0'>" +
                                             "<Value.ValueParts>" +
                                             "<ValuePart Title='Numerator'  Value='1' />" +
                                             "<ValuePart Title='Denominator'  Value='1' />" +
                                             "</Value.ValueParts>" +
                                             "</RatioValue>" +
                                             "</MediaTypeItem>" +
                                             "<MediaTypeItem Name='MF_MT_PIXEL_ASPECT_RATIO' GUID='{C6376A1E-8D0A-4027-BE45-6D9A0AD39BB6}' Title='Pixel aspect ratio.' Description='Pixel aspect ratio for a video media type.'>" +
                                             "<RatioValue  Value='1'>" +
                                             "<Value.ValueParts>" +
                                             "<ValuePart Title='Numerator'  Value='1' />" +
                                             "<ValuePart Title='Denominator'  Value='1' />" +
                                             "</Value.ValueParts>" +
                                             "</RatioValue>" +
                                             "</MediaTypeItem>" +
                                             "<MediaTypeItem Name='MF_MT_ALL_SAMPLES_INDEPENDENT' GUID='{C9173739-5E56-461C-B713-46FB995CB95F}' Title='Independent of samples.' Description='Specifies for a media type whether each sample is independent of the other samples in the stream.'>" +
                                             "<SingleValue Value='True' />" +
                                             "</MediaTypeItem>" +
                                             "<MediaTypeItem Name='MF_MT_SAMPLE_SIZE' GUID='{DAD3AB78-1990-408B-BCE2-EBA673DACC10}' Title='The fixed size of each sample in stream.' Description='Specifies the size of each sample, in bytes, in a media type.'>" +
                                             "<SingleValue Value='Temp_SampleSize' />" +
                                             "</MediaTypeItem>" +
                                             "<MediaTypeItem Name='MF_MT_INTERLACE_MODE' GUID='{E2724BB8-E676-4806-B4B2-A8D6EFB44CCD}' Title='Describes how the frames are interlaced.' Description='Describes how the frames in a video media type are interlaced.'>" +
                                             "<SingleValue Value='MFVideoInterlace_Progressive' />" +
                                             "</MediaTypeItem>" +
                                             "<MediaTypeItem Name='MF_MT_SUBTYPE' GUID='{F7E34C9A-42E8-4714-B74B-CB29D72C35E5}' Title='Subtype GUID for a media type.' Description='The subtype GUID defines a specific media format type within a major type.'>" +
                                             "<SingleValue GUID='{Temp_SubTypeGUID}' />" +
                                             "</MediaTypeItem>" +
                                             "</MediaType>" +
                                             "</MediaTypes>" +
                                             "</StreamDescriptor>" +
                                             "</PresentationDescriptor>";

            IPCameraMJPEGCaptureProcessor lICaptureProcessor = new IPCameraMJPEGCaptureProcessor();

            lICaptureProcessor.mURL = aURL;

            {
                HttpWebRequest req = (HttpWebRequest)WebRequest.Create(aURL);

                WebResponse resp = req.GetResponse();

                // check content type
                string ct = resp.ContentType;
                if (ct.IndexOf("multipart/x-mixed-replace") == -1)
                {
                    throw new ApplicationException("Invalid URL");
                }

                byte[] boundary = null;

                int boundaryLen, delimiterLen = 0, delimiter2Len = 0;

                Stream stream = null;

                // get boundary
                ASCIIEncoding encoding = new ASCIIEncoding();
                boundary    = encoding.GetBytes(ct.Substring(ct.IndexOf("boundary=", 0) + 9));
                boundaryLen = boundary.Length;

                // get response stream
                stream = resp.GetResponseStream();

                int read, todo = 0, total = 0, pos = 0, align = 1;
                int start = 0, stop = 0;

                byte[] buffer = new byte[bufSize];

                byte[] delimiter  = null;
                byte[] delimiter2 = null;

                MemoryStream lMemoryStream = null;

                do
                {
                    if ((read = stream.Read(buffer, total, readSize)) == 0)
                    {
                        throw new ApplicationException();
                    }

                    total += read;
                    todo  += read;

                    // does we know the delimiter ?
                    if (delimiter == null)
                    {
                        // find boundary
                        pos = ByteArrayUtils.Find(buffer, boundary, pos, todo);

                        if (pos == -1)
                        {
                            // was not found
                            todo = boundaryLen - 1;
                            pos  = total - todo;
                            continue;
                        }

                        todo = total - pos;

                        if (todo < 2)
                        {
                            continue;
                        }

                        // check new line delimiter type
                        if (buffer[pos + boundaryLen] == 10)
                        {
                            delimiterLen = 2;
                            delimiter    = new byte[2] {
                                10, 10
                            };
                            delimiter2Len = 1;
                            delimiter2    = new byte[1] {
                                10
                            };
                        }
                        else
                        {
                            delimiterLen = 4;
                            delimiter    = new byte[4] {
                                13, 10, 13, 10
                            };
                            delimiter2Len = 2;
                            delimiter2    = new byte[2] {
                                13, 10
                            };
                        }

                        pos += boundaryLen + delimiter2Len;
                        todo = total - pos;
                    }

                    // search for image
                    if (align == 1)
                    {
                        start = ByteArrayUtils.Find(buffer, delimiter, pos, todo);
                        if (start != -1)
                        {
                            // found delimiter
                            start += delimiterLen;
                            pos    = start;
                            todo   = total - pos;
                            align  = 2;
                        }
                        else
                        {
                            // delimiter not found
                            todo = delimiterLen - 1;
                            pos  = total - todo;
                        }
                    }

                    bool lout = false;

                    // search for image end
                    while ((align == 2) && (todo >= boundaryLen))
                    {
                        stop = ByteArrayUtils.Find(buffer, boundary, pos, todo);
                        if (stop != -1)
                        {
                            pos  = stop;
                            todo = total - pos;

                            lMemoryStream = new MemoryStream(buffer, start, stop - start);

                            var l = JpegBitmapDecoder.Create(lMemoryStream, BitmapCreateOptions.None, BitmapCacheOption.None);

                            if (l != null && l.Frames.Count > 0)
                            {
                                var lFrame = l.Frames[0];

                                lICaptureProcessor.mWidth = lFrame.PixelWidth;

                                lICaptureProcessor.mHeight = lFrame.PixelHeight;

                                lout = true;

                                break;
                            }


                            // increment frames counter
                            //framesReceived++;

                            //// image at stop
                            //if (NewFrame != null)
                            //{
                            //    Bitmap bmp = (Bitmap)Bitmap.FromStream(new MemoryStream(buffer, start, stop - start));
                            //    // notify client
                            //    NewFrame(this, new CameraEventArgs(bmp));
                            //    // release the image
                            //    bmp.Dispose();
                            //    bmp = null;
                            //}

                            // shift array
                            pos  = stop + boundaryLen;
                            todo = total - pos;
                            //Array.Copy(buffer, pos, buffer, 0, todo);

                            total = todo;
                            pos   = 0;
                            align = 1;
                        }
                        else
                        {
                            // delimiter not found
                            todo = boundaryLen - 1;
                            pos  = total - todo;
                        }
                    }

                    if (lout)
                    {
                        break;
                    }
                } while (true);

                stream.Close();

                resp.Close();

                //System.Windows.Forms.MessageBox.Show(ct);

                int lStride = 0;

                lock (lICaptureProcessor)
                {
                    if (lICaptureProcessor.mRawData != IntPtr.Zero)
                    {
                        Marshal.FreeHGlobal(lICaptureProcessor.mRawData);

                        lICaptureProcessor.mRawData = IntPtr.Zero;
                    }

                    lICaptureProcessor.mLength = stop - start;

                    lICaptureProcessor.mRawData = Marshal.AllocHGlobal(lICaptureProcessor.mLength);

                    Marshal.Copy(buffer, start, lICaptureProcessor.mRawData, stop - start);
                }



                lPresentationDescriptor = lPresentationDescriptor.Replace("Temp_Width", ((uint)lICaptureProcessor.mWidth).ToString());

                lPresentationDescriptor = lPresentationDescriptor.Replace("Temp_Height", ((uint)lICaptureProcessor.mHeight).ToString());

                lPresentationDescriptor = lPresentationDescriptor.Replace("Temp_Stride", lStride.ToString());

                lPresentationDescriptor = lPresentationDescriptor.Replace("Temp_SampleSize", ((uint)(lICaptureProcessor.mWidth * lICaptureProcessor.mHeight * 4)).ToString());

                lPresentationDescriptor = lPresentationDescriptor.Replace("Temp_SubTypeGUID", MFVideoFormat_MJPG.ToString());

                lICaptureProcessor.mPresentationDescriptor = lPresentationDescriptor;
            }


            return(lICaptureProcessor);
        }