Пример #1
0
        internal CameraResolution GetResolution(List <CameraResolution> availableResolutions)
        {
            CameraResolution r = null;

            var dg = CameraResolutionSelector;

            if (dg != null)
            {
                r = dg(availableResolutions);
            }

            return(r);
        }
        bool SetupCaptureSession()
        {
            var started = DateTime.UtcNow;

            var availableResolutions = new List <CameraResolution> ();

            var consideredResolutions = new Dictionary <NSString, CameraResolution> {
                { AVCaptureSession.Preset352x288, new CameraResolution   {
                      Width = 352, Height = 288
                  } },
                { AVCaptureSession.PresetMedium, new CameraResolution    {
                      Width = 480, Height = 360
                  } },                                                                                                          //480x360
                { AVCaptureSession.Preset640x480, new CameraResolution   {
                      Width = 640, Height = 480
                  } },
                { AVCaptureSession.Preset1280x720, new CameraResolution  {
                      Width = 1280, Height = 720
                  } },
                { AVCaptureSession.Preset1920x1080, new CameraResolution {
                      Width = 1920, Height = 1080
                  } }
            };

            // configure the capture session for low resolution, change this if your code
            // can cope with more data or volume
            session = new AVCaptureSession()
            {
                SessionPreset = AVCaptureSession.Preset640x480
            };

            // create a device input and attach it to the session
//			var captureDevice = AVCaptureDevice.DefaultDeviceWithMediaType (AVMediaType.Video);
            AVCaptureDevice captureDevice = null;
            var             devices       = AVCaptureDevice.DevicesWithMediaType(AVMediaType.Video);

            foreach (var device in devices)
            {
                captureDevice = device;
                if (options.UseFrontCameraIfAvailable.HasValue &&
                    options.UseFrontCameraIfAvailable.Value &&
                    device.Position == AVCaptureDevicePosition.Front)
                {
                    break;                     //Front camera successfully set
                }
                else if (device.Position == AVCaptureDevicePosition.Back && (!options.UseFrontCameraIfAvailable.HasValue || !options.UseFrontCameraIfAvailable.Value))
                {
                    break;                     //Back camera succesfully set
                }
            }
            if (captureDevice == null)
            {
                Console.WriteLine("No captureDevice - this won't work on the simulator, try a physical device");
                if (overlayView != null)
                {
                    this.AddSubview(overlayView);
                    this.BringSubviewToFront(overlayView);
                }
                return(false);
            }

            CameraResolution resolution = null;

            // Find resolution
            // Go through the resolutions we can even consider
            foreach (var cr in consideredResolutions)
            {
                // Now check to make sure our selected device supports the resolution
                // so we can add it to the list to pick from
                if (captureDevice.SupportsAVCaptureSessionPreset(cr.Key))
                {
                    availableResolutions.Add(cr.Value);
                }
            }

            resolution = options.GetResolution(availableResolutions);

            // See if the user selected a resolution
            if (resolution != null)
            {
                // Now get the preset string from the resolution chosen
                var preset = (from c in consideredResolutions
                              where c.Value.Width == resolution.Width &&
                              c.Value.Height == resolution.Height
                              select c.Key).FirstOrDefault();

                // If we found a matching preset, let's set it on the session
                if (!string.IsNullOrEmpty(preset))
                {
                    session.SessionPreset = preset;
                }
            }

            var input = AVCaptureDeviceInput.FromDevice(captureDevice);

            if (input == null)
            {
                Console.WriteLine("No input - this won't work on the simulator, try a physical device");
                if (overlayView != null)
                {
                    this.AddSubview(overlayView);
                    this.BringSubviewToFront(overlayView);
                }
                return(false);
            }
            else
            {
                session.AddInput(input);
            }


            var startedAVPreviewLayerAlloc = DateTime.UtcNow;

            previewLayer = new AVCaptureVideoPreviewLayer(session);

            var totalAVPreviewLayerAlloc = DateTime.UtcNow - startedAVPreviewLayerAlloc;

            Console.WriteLine("PERF: Alloc AVCaptureVideoPreviewLayer took {0} ms.", totalAVPreviewLayerAlloc.TotalMilliseconds);


            // //Framerate set here (15 fps)
            // if (UIDevice.CurrentDevice.CheckSystemVersion (7, 0))
            // {
            //  var perf1 = PerformanceCounter.Start ();

            //  NSError lockForConfigErr = null;

            //  captureDevice.LockForConfiguration (out lockForConfigErr);
            //  if (lockForConfigErr == null)
            //  {
            //      captureDevice.ActiveVideoMinFrameDuration = new CMTime (1, 10);
            //      captureDevice.UnlockForConfiguration ();
            //  }

            //  PerformanceCounter.Stop (perf1, "PERF: ActiveVideoMinFrameDuration Took {0} ms");
            // }
            //          else
            //              previewLayer.Connection.VideoMinFrameDuration = new CMTime(1, 10);


            var perf2 = PerformanceCounter.Start();

                        #if __UNIFIED__
            previewLayer.VideoGravity = AVLayerVideoGravity.ResizeAspectFill;
                        #else
            previewLayer.LayerVideoGravity = AVLayerVideoGravity.ResizeAspectFill;
                        #endif
            previewLayer.Frame    = new CGRect(0, 0, this.Frame.Width, this.Frame.Height);
            previewLayer.Position = new CGPoint(this.Layer.Bounds.Width / 2, (this.Layer.Bounds.Height / 2));

            layerView = new UIView(new CGRect(0, 0, this.Frame.Width, this.Frame.Height));
            layerView.AutoresizingMask = UIViewAutoresizing.FlexibleWidth | UIViewAutoresizing.FlexibleHeight;
            layerView.Layer.AddSublayer(previewLayer);

            this.AddSubview(layerView);

            ResizePreview(UIApplication.SharedApplication.StatusBarOrientation);

            if (overlayView != null)
            {
                this.AddSubview(overlayView);
                this.BringSubviewToFront(overlayView);

                //overlayView.LayoutSubviews ();
            }

            PerformanceCounter.Stop(perf2, "PERF: Setting up layers took {0} ms");

            var perf3 = PerformanceCounter.Start();

            session.StartRunning();

            PerformanceCounter.Stop(perf3, "PERF: session.StartRunning() took {0} ms");

            var perf4 = PerformanceCounter.Start();

            var videoSettings = NSDictionary.FromObjectAndKey(new NSNumber((int)CVPixelFormatType.CV32BGRA),
                                                              CVPixelBuffer.PixelFormatTypeKey);


            // create a VideoDataOutput and add it to the sesion
            output = new AVCaptureVideoDataOutput {
                WeakVideoSettings = videoSettings
            };

            // configure the output
            queue = new DispatchQueue("ZxingScannerView");             // (Guid.NewGuid().ToString());

            var barcodeReader = new BarcodeReaderiOS(null, (img) =>
            {
                var src = new RGBLuminanceSourceiOS(img);                 //, bmp.Width, bmp.Height);

                //Don't try and rotate properly if we're autorotating anyway
                if (ScanningOptions.AutoRotate.HasValue && ScanningOptions.AutoRotate.Value)
                {
                    return(src);
                }

                var tmpInterfaceOrientation = UIInterfaceOrientation.Portrait;
                InvokeOnMainThread(() => tmpInterfaceOrientation = UIApplication.SharedApplication.StatusBarOrientation);

                switch (tmpInterfaceOrientation)
                {
                case UIInterfaceOrientation.Portrait:
                    return(src.rotateCounterClockwise().rotateCounterClockwise().rotateCounterClockwise());

                case UIInterfaceOrientation.PortraitUpsideDown:
                    return(src.rotateCounterClockwise().rotateCounterClockwise().rotateCounterClockwise());

                case UIInterfaceOrientation.LandscapeLeft:
                    return(src);

                case UIInterfaceOrientation.LandscapeRight:
                    return(src);
                }

                return(src);
            }, null, null);             //(p, w, h, f) => new RGBLuminanceSource(p, w, h, RGBLuminanceSource.BitmapFormat.Unknown));

            if (ScanningOptions.TryHarder.HasValue)
            {
                Console.WriteLine("TRY_HARDER: " + ScanningOptions.TryHarder.Value);
                barcodeReader.Options.TryHarder = ScanningOptions.TryHarder.Value;
            }
            if (ScanningOptions.PureBarcode.HasValue)
            {
                barcodeReader.Options.PureBarcode = ScanningOptions.PureBarcode.Value;
            }
            if (ScanningOptions.AutoRotate.HasValue)
            {
                Console.WriteLine("AUTO_ROTATE: " + ScanningOptions.AutoRotate.Value);
                barcodeReader.AutoRotate = ScanningOptions.AutoRotate.Value;
            }
            if (!string.IsNullOrEmpty(ScanningOptions.CharacterSet))
            {
                barcodeReader.Options.CharacterSet = ScanningOptions.CharacterSet;
            }
            if (ScanningOptions.TryInverted.HasValue)
            {
                barcodeReader.TryInverted = ScanningOptions.TryInverted.Value;
            }

            if (ScanningOptions.PossibleFormats != null && ScanningOptions.PossibleFormats.Count > 0)
            {
                barcodeReader.Options.PossibleFormats = new List <BarcodeFormat>();

                foreach (var pf in ScanningOptions.PossibleFormats)
                {
                    barcodeReader.Options.PossibleFormats.Add(pf);
                }
            }

            outputRecorder = new OutputRecorder(ScanningOptions, img =>
            {
                if (!IsAnalyzing)
                {
                    return(false);
                }

                try
                {
                    //var sw = new System.Diagnostics.Stopwatch();
                    //sw.Start();

                    var rs = barcodeReader.Decode(img);

                    //sw.Stop();

                    //Console.WriteLine("Decode Time: {0} ms", sw.ElapsedMilliseconds);

                    if (rs != null)
                    {
                        resultCallback(rs);
                        return(true);
                    }
                }
                catch (Exception ex)
                {
                    Console.WriteLine("DECODE FAILED: " + ex);
                }

                return(false);
            });

            output.AlwaysDiscardsLateVideoFrames = true;
            output.SetSampleBufferDelegate(outputRecorder, queue);

            PerformanceCounter.Stop(perf4, "PERF: SetupCamera Finished.  Took {0} ms.");

            session.AddOutput(output);
            //session.StartRunning ();


            var perf5 = PerformanceCounter.Start();

            NSError err = null;
            if (captureDevice.LockForConfiguration(out err))
            {
                if (captureDevice.IsFocusModeSupported(AVCaptureFocusMode.ContinuousAutoFocus))
                {
                    captureDevice.FocusMode = AVCaptureFocusMode.ContinuousAutoFocus;
                }
                else if (captureDevice.IsFocusModeSupported(AVCaptureFocusMode.AutoFocus))
                {
                    captureDevice.FocusMode = AVCaptureFocusMode.AutoFocus;
                }

                if (captureDevice.IsExposureModeSupported(AVCaptureExposureMode.ContinuousAutoExposure))
                {
                    captureDevice.ExposureMode = AVCaptureExposureMode.ContinuousAutoExposure;
                }
                else if (captureDevice.IsExposureModeSupported(AVCaptureExposureMode.AutoExpose))
                {
                    captureDevice.ExposureMode = AVCaptureExposureMode.AutoExpose;
                }

                if (captureDevice.IsWhiteBalanceModeSupported(AVCaptureWhiteBalanceMode.ContinuousAutoWhiteBalance))
                {
                    captureDevice.WhiteBalanceMode = AVCaptureWhiteBalanceMode.ContinuousAutoWhiteBalance;
                }
                else if (captureDevice.IsWhiteBalanceModeSupported(AVCaptureWhiteBalanceMode.AutoWhiteBalance))
                {
                    captureDevice.WhiteBalanceMode = AVCaptureWhiteBalanceMode.AutoWhiteBalance;
                }

                if (UIDevice.CurrentDevice.CheckSystemVersion(7, 0) && captureDevice.AutoFocusRangeRestrictionSupported)
                {
                    captureDevice.AutoFocusRangeRestriction = AVCaptureAutoFocusRangeRestriction.Near;
                }

                if (captureDevice.FocusPointOfInterestSupported)
                {
                    captureDevice.FocusPointOfInterest = new PointF(0.5f, 0.5f);
                }

                if (captureDevice.ExposurePointOfInterestSupported)
                {
                    captureDevice.ExposurePointOfInterest = new PointF(0.5f, 0.5f);
                }

                captureDevice.UnlockForConfiguration();
            }
            else
            {
                Console.WriteLine("Failed to Lock for Config: " + err.Description);
            }

            PerformanceCounter.Stop(perf5, "PERF: Setup Focus in {0} ms.");

            return(true);
        }
Пример #3
0
        public async Task StartScanningAsync(Action <Result> scanResultCallback, MobileBarcodeScanningOptions options = null)
        {
            this.callback        = scanResultCallback;
            this.scanningOptions = options ?? MobileBarcodeScanningOptions.Default;

            lastPreviewAnalysis = DateTime.UtcNow.AddMilliseconds(this.scanningOptions.InitialDelayBeforeAnalyzingFrames);
            isAnalyzing         = true;

            Console.WriteLine("StartScanning");

            CheckCameraPermissions();

            var perf = PerformanceCounter.Start();

            GetExclusiveAccess();

            try {
                var version = Build.VERSION.SdkInt;

                if (version >= BuildVersionCodes.Gingerbread)
                {
                    Android.Util.Log.Debug(MobileBarcodeScanner.TAG, "Checking Number of cameras...");

                    var numCameras = Camera.NumberOfCameras;
                    var camInfo    = new Camera.CameraInfo();
                    var found      = false;
                    Android.Util.Log.Debug(MobileBarcodeScanner.TAG, "Found " + numCameras + " cameras...");

                    var whichCamera = CameraFacing.Back;

                    if (this.scanningOptions.UseFrontCameraIfAvailable.HasValue && this.scanningOptions.UseFrontCameraIfAvailable.Value)
                    {
                        whichCamera = CameraFacing.Front;
                    }

                    for (int i = 0; i < numCameras; i++)
                    {
                        Camera.GetCameraInfo(i, camInfo);
                        if (camInfo.Facing == whichCamera)
                        {
                            Android.Util.Log.Debug(MobileBarcodeScanner.TAG, "Found " + whichCamera + " Camera, opening...");
                            camera   = Camera.Open(i);
                            cameraId = i;
                            found    = true;
                            break;
                        }
                    }

                    if (!found)
                    {
                        Android.Util.Log.Debug(MobileBarcodeScanner.TAG, "Finding " + whichCamera + " camera failed, opening camera 0...");
                        camera   = Camera.Open(0);
                        cameraId = 0;
                    }
                }
                else
                {
                    camera = Camera.Open();
                }

                if (camera == null)
                {
                    Android.Util.Log.Debug(MobileBarcodeScanner.TAG, "Camera is null :(");
                }

                camera.SetPreviewCallback(this);
            } catch (Exception ex) {
                ShutdownCamera();

                Console.WriteLine("Setup Error: " + ex);
            }

            PerformanceCounter.Stop(perf, "Camera took {0}ms");

            if (!surfaceChanged)
            {
                await waitSurface.WaitAsync();
            }

            if (camera == null)
            {
                return;
            }

            perf = PerformanceCounter.Start();

            var parameters = camera.GetParameters();

            parameters.PreviewFormat = ImageFormatType.Nv21;


            var availableResolutions = new List <CameraResolution> ();

            foreach (var sps in parameters.SupportedPreviewSizes)
            {
                availableResolutions.Add(new CameraResolution {
                    Width  = sps.Width,
                    Height = sps.Height
                });
            }

            // Try and get a desired resolution from the options selector
            var resolution = scanningOptions.GetResolution(availableResolutions);

            // If the user did not specify a resolution, let's try and find a suitable one
            if (resolution == null)
            {
                // Loop through all supported sizes
                foreach (var sps in parameters.SupportedPreviewSizes)
                {
                    // Find one that's >= 640x360 but <= 1000x1000
                    // This will likely pick the *smallest* size in that range, which should be fine
                    if (sps.Width >= 640 && sps.Width <= 1000 && sps.Height >= 360 && sps.Height <= 1000)
                    {
                        resolution = new CameraResolution {
                            Width  = sps.Width,
                            Height = sps.Height
                        };
                        break;
                    }
                }
            }

            // Google Glass requires this fix to display the camera output correctly
            if (Build.Model.Contains("Glass"))
            {
                resolution = new CameraResolution {
                    Width  = 640,
                    Height = 360
                };
                // Glass requires 30fps
                parameters.SetPreviewFpsRange(30000, 30000);
            }

            // Hopefully a resolution was selected at some point
            if (resolution != null)
            {
                Android.Util.Log.Debug(MobileBarcodeScanner.TAG, "Selected Resolution: " + resolution.Width + "x" + resolution.Height);
                parameters.SetPreviewSize(resolution.Width, resolution.Height);
            }

            camera.SetParameters(parameters);

            SetCameraDisplayOrientation(this.activity);

            camera.SetPreviewDisplay(this.Holder);
            camera.StartPreview();

            PerformanceCounter.Stop(perf, "SurfaceChanged took {0}ms");

            AutoFocus();
        }
        public async Task StartScanningAsync(Action<ZXing.Result> scanCallback, MobileBarcodeScanningOptions options = null)
        {
            if (stopping)
                return;

            isAnalyzing = true;
            ScanCallback = scanCallback;
            ScanningOptions = options ?? MobileBarcodeScanningOptions.Default;

            topText.Text = TopText ?? string.Empty;
            bottomText.Text = BottomText ?? string.Empty;

            if (UseCustomOverlay)
            {
                gridCustomOverlay.Children.Clear();
                if (CustomOverlay != null)
                    gridCustomOverlay.Children.Add(CustomOverlay);

                gridCustomOverlay.Visibility = Visibility.Visible;
                gridDefaultOverlay.Visibility = Visibility.Collapsed;
            }
            else
            {
                gridCustomOverlay.Visibility = Visibility.Collapsed;
                gridDefaultOverlay.Visibility = Visibility.Visible;
            }

            // Find which device to use
            var preferredCamera = await this.GetFilteredCameraOrDefaultAsync(ScanningOptions);            
            mediaCapture = new MediaCapture();
            
            // Initialize the capture with the settings above
            await mediaCapture.InitializeAsync(new MediaCaptureInitializationSettings()
            {
                StreamingCaptureMode = StreamingCaptureMode.Video,
                VideoDeviceId = preferredCamera.Id
            });

            // Set the capture element's source to show it in the UI
            captureElement.Source = mediaCapture;

            // Start the preview
            await mediaCapture.StartPreviewAsync();
            
            // Get all the available resolutions for preview
            var availableProperties = mediaCapture.VideoDeviceController.GetAvailableMediaStreamProperties(MediaStreamType.VideoPreview);
            var availableResolutions = new List<CameraResolution>();
            foreach (var ap in availableProperties)
            {
                var vp = (VideoEncodingProperties)ap;
                System.Diagnostics.Debug.WriteLine("Camera Preview Resolution: {0}x{1}", vp.Width, vp.Height);
                availableResolutions.Add(new CameraResolution { Width = (int)vp.Width, Height = (int)vp.Height });                
            }
            CameraResolution previewResolution = null;
            if (ScanningOptions.CameraResolutionSelector != null)
                previewResolution = ScanningOptions.CameraResolutionSelector(availableResolutions);

            // If the user did not specify a resolution, let's try and find a suitable one
            if (previewResolution == null)
            {
                // Loop through all supported sizes
                foreach (var sps in availableResolutions)
                {
                    // Find one that's >= 640x360 but <= 1000x1000
                    // This will likely pick the *smallest* size in that range, which should be fine
                    if (sps.Width >= 640 && sps.Width <= 1000 && sps.Height >= 360 && sps.Height <= 1000)
                    {
                        previewResolution = new CameraResolution
                        {
                            Width = sps.Width,
                            Height = sps.Height
                        };
                        break;
                    }
                }
            }

            if (previewResolution == null)
                previewResolution = availableResolutions.LastOrDefault();

            System.Diagnostics.Debug.WriteLine("Using Preview Resolution: {0}x{1}", previewResolution.Width, previewResolution.Height);

            // Find the matching property based on the selection, again
            var chosenProp = availableProperties.FirstOrDefault(ap => ((VideoEncodingProperties)ap).Width == previewResolution.Width && ((VideoEncodingProperties)ap).Height == previewResolution.Height);
            
            // Set the selected resolution
            await mediaCapture.VideoDeviceController.SetMediaStreamPropertiesAsync(MediaStreamType.VideoPreview, chosenProp);

            await SetPreviewRotationAsync();

            captureElement.Stretch = Stretch.UniformToFill;

            // Get our preview properties
            var previewProperties = mediaCapture.VideoDeviceController.GetMediaStreamProperties(MediaStreamType.VideoPreview) as VideoEncodingProperties;
            
            // Setup a frame to use as the input settings
            var destFrame = new VideoFrame(Windows.Graphics.Imaging.BitmapPixelFormat.Bgra8, (int)previewProperties.Width, (int)previewProperties.Height);

            var zxing = ScanningOptions.BuildBarcodeReader();

            timerPreview = new Timer(async (state) => {
                if (stopping)
                    return;                               
                if (mediaCapture == null || mediaCapture.CameraStreamState != Windows.Media.Devices.CameraStreamState.Streaming)
                    return;
                if (processing)
                    return;
                if (!isAnalyzing)
                    return;

                processing = true;

                SoftwareBitmapLuminanceSource luminanceSource = null;

                try
                {

                    // Get preview 
                    var frame = await mediaCapture.GetPreviewFrameAsync(destFrame);

                    // Create our luminance source
                    luminanceSource = new SoftwareBitmapLuminanceSource(frame.SoftwareBitmap);

                } catch (Exception ex)
                {
                    System.Diagnostics.Debug.WriteLine("GetPreviewFrame Failed: {0}", ex);
                }

                ZXing.Result result = null;

                try
                {
                    // Try decoding the image
                    if (luminanceSource != null)
                        result = zxing.Decode(luminanceSource);
                }
                catch (Exception ex)
                {
                    
                }

                // Check if a result was found
                if (result != null && !string.IsNullOrEmpty (result.Text))
                {
                    if (!ContinuousScanning)
                        await StopScanningAsync();
                    LastScanResult = result;
                    ScanCallback(result);                    
                }

                processing = false;
                         
            }, null, TimeSpan.FromMilliseconds(200), TimeSpan.FromMilliseconds(200));           
        }
        bool SetupCaptureSession()
        {
            var availableResolutions = new List <CameraResolution> ();

            var consideredResolutions = new Dictionary <NSString, CameraResolution> {
                { AVCaptureSession.Preset352x288, new CameraResolution   {
                      Width = 352, Height = 288
                  } },
                { AVCaptureSession.PresetMedium, new CameraResolution    {
                      Width = 480, Height = 360
                  } },                                                                                      //480x360
                { AVCaptureSession.Preset640x480, new CameraResolution   {
                      Width = 640, Height = 480
                  } },
                { AVCaptureSession.Preset1280x720, new CameraResolution  {
                      Width = 1280, Height = 720
                  } },
                { AVCaptureSession.Preset1920x1080, new CameraResolution {
                      Width = 1920, Height = 1080
                  } }
            };

            // configure the capture session for low resolution, change this if your code
            // can cope with more data or volume
            session = new AVCaptureSession()
            {
                SessionPreset = AVCaptureSession.Preset640x480
            };

            // create a device input and attach it to the session
//			var captureDevice = AVCaptureDevice.DefaultDeviceWithMediaType (AVMediaType.Video);
            AVCaptureDevice captureDevice = null;
            var             devices       = AVCaptureDevice.DevicesWithMediaType(AVMediaType.Video);

            foreach (var device in devices)
            {
                captureDevice = device;
                if (options.UseFrontCameraIfAvailable.HasValue &&
                    options.UseFrontCameraIfAvailable.Value &&
                    device.Position == AVCaptureDevicePosition.Front)
                {
                    break;                     //Front camera successfully set
                }
                else if (device.Position == AVCaptureDevicePosition.Back && (!options.UseFrontCameraIfAvailable.HasValue || !options.UseFrontCameraIfAvailable.Value))
                {
                    break;                     //Back camera succesfully set
                }
            }
            if (captureDevice == null)
            {
                Console.WriteLine("No captureDevice - this won't work on the simulator, try a physical device");
                if (overlayView != null)
                {
                    this.AddSubview(overlayView);
                    this.BringSubviewToFront(overlayView);
                }
                return(false);
            }

            CameraResolution resolution = null;

            // Find resolution
            // Go through the resolutions we can even consider
            foreach (var cr in consideredResolutions)
            {
                // Now check to make sure our selected device supports the resolution
                // so we can add it to the list to pick from
                if (captureDevice.SupportsAVCaptureSessionPreset(cr.Key))
                {
                    availableResolutions.Add(cr.Value);
                }
            }

            resolution = options.GetResolution(availableResolutions);

            // See if the user selected a resolution
            if (resolution != null)
            {
                // Now get the preset string from the resolution chosen
                var preset = (from c in consideredResolutions
                              where c.Value.Width == resolution.Width &&
                              c.Value.Height == resolution.Height
                              select c.Key).FirstOrDefault();

                // If we found a matching preset, let's set it on the session
                if (!string.IsNullOrEmpty(preset))
                {
                    session.SessionPreset = preset;
                }
            }

            var input = AVCaptureDeviceInput.FromDevice(captureDevice);

            if (input == null)
            {
                Console.WriteLine("No input - this won't work on the simulator, try a physical device");
                if (overlayView != null)
                {
                    this.AddSubview(overlayView);
                    this.BringSubviewToFront(overlayView);
                }
                return(false);
            }
            else
            {
                session.AddInput(input);
            }


            foundResult = false;
            //Detect barcodes with built in avcapture stuff
            AVCaptureMetadataOutput metadataOutput = new AVCaptureMetadataOutput();

            captureDelegate = new CaptureDelegate(metaDataObjects =>
            {
                if (!analyzing)
                {
                    return;
                }

                //Console.WriteLine("Found MetaData Objects");

                var msSinceLastPreview = (DateTime.UtcNow - lastAnalysis).TotalMilliseconds;

                if (msSinceLastPreview < options.DelayBetweenAnalyzingFrames ||
                    (wasScanned && msSinceLastPreview < options.DelayBetweenContinuousScans) ||
                    working)
                //|| CancelTokenSource.IsCancellationRequested)
                {
                    return;
                }

                working      = true;
                wasScanned   = false;
                lastAnalysis = DateTime.UtcNow;

                var mdo = metaDataObjects.FirstOrDefault();

                if (mdo == null)
                {
                    return;
                }

                var readableObj = mdo as AVMetadataMachineReadableCodeObject;

                if (readableObj == null)
                {
                    return;
                }

                wasScanned = true;

                var zxingFormat = ZXingBarcodeFormatFromAVCaptureBarcodeFormat(readableObj.Type.ToString());

                var rs = new ZXing.Result(readableObj.StringValue, null, null, zxingFormat);

                resultCallback(rs);

                working = false;
            });

            metadataOutput.SetDelegate(captureDelegate, DispatchQueue.MainQueue);
            session.AddOutput(metadataOutput);

            //Setup barcode formats
            if (ScanningOptions.PossibleFormats != null && ScanningOptions.PossibleFormats.Count > 0)
            {
                #if __UNIFIED__
                var formats = AVMetadataObjectType.None;

                foreach (var f in ScanningOptions.PossibleFormats)
                {
                    formats |= AVCaptureBarcodeFormatFromZXingBarcodeFormat(f);
                }

                formats &= ~AVMetadataObjectType.None;

                metadataOutput.MetadataObjectTypes = formats;
                #else
                var formats = new List <string> ();

                foreach (var f in ScanningOptions.PossibleFormats)
                {
                    formats.AddRange(AVCaptureBarcodeFormatFromZXingBarcodeFormat(f));
                }

                metadataOutput.MetadataObjectTypes = (from f in formats.Distinct() select new NSString(f)).ToArray();
                #endif
            }
            else
            {
                metadataOutput.MetadataObjectTypes = metadataOutput.AvailableMetadataObjectTypes;
            }



            previewLayer = new AVCaptureVideoPreviewLayer(session);

            //Framerate set here (15 fps)
            if (previewLayer.RespondsToSelector(new Selector("connection")))
            {
                if (UIDevice.CurrentDevice.CheckSystemVersion(7, 0))
                {
                    var perf1 = PerformanceCounter.Start();

                    NSError lockForConfigErr = null;

                    captureDevice.LockForConfiguration(out lockForConfigErr);
                    if (lockForConfigErr == null)
                    {
                        captureDevice.ActiveVideoMinFrameDuration = new CMTime(1, 10);
                        captureDevice.UnlockForConfiguration();
                    }

                    PerformanceCounter.Stop(perf1, "PERF: ActiveVideoMinFrameDuration Took {0} ms");
                }
                else
                {
                    previewLayer.Connection.VideoMinFrameDuration = new CMTime(1, 10);
                }
            }

                        #if __UNIFIED__
            previewLayer.VideoGravity = AVLayerVideoGravity.ResizeAspectFill;
                        #else
            previewLayer.LayerVideoGravity = AVLayerVideoGravity.ResizeAspectFill;
                        #endif
            previewLayer.Frame    = new CGRect(0, 0, this.Frame.Width, this.Frame.Height);
            previewLayer.Position = new CGPoint(this.Layer.Bounds.Width / 2, (this.Layer.Bounds.Height / 2));

            layerView = new UIView(new CGRect(0, 0, this.Frame.Width, this.Frame.Height));
            layerView.AutoresizingMask = UIViewAutoresizing.FlexibleWidth | UIViewAutoresizing.FlexibleHeight;
            layerView.Layer.AddSublayer(previewLayer);

            this.AddSubview(layerView);

            ResizePreview(UIApplication.SharedApplication.StatusBarOrientation);

            if (overlayView != null)
            {
                this.AddSubview(overlayView);
                this.BringSubviewToFront(overlayView);

                //overlayView.LayoutSubviews ();
            }

            session.StartRunning();

            Console.WriteLine("RUNNING!!!");



            //output.AlwaysDiscardsLateVideoFrames = true;


            Console.WriteLine("SetupCamera Finished");

            //session.AddOutput (output);
            //session.StartRunning ();


            if (captureDevice.IsFocusModeSupported(AVCaptureFocusMode.ContinuousAutoFocus))
            {
                NSError err = null;
                if (captureDevice.LockForConfiguration(out err))
                {
                    if (captureDevice.IsFocusModeSupported(AVCaptureFocusMode.ContinuousAutoFocus))
                    {
                        captureDevice.FocusMode = AVCaptureFocusMode.ContinuousAutoFocus;
                    }
                    else if (captureDevice.IsFocusModeSupported(AVCaptureFocusMode.AutoFocus))
                    {
                        captureDevice.FocusMode = AVCaptureFocusMode.AutoFocus;
                    }

                    if (captureDevice.IsExposureModeSupported(AVCaptureExposureMode.ContinuousAutoExposure))
                    {
                        captureDevice.ExposureMode = AVCaptureExposureMode.ContinuousAutoExposure;
                    }
                    else if (captureDevice.IsExposureModeSupported(AVCaptureExposureMode.AutoExpose))
                    {
                        captureDevice.ExposureMode = AVCaptureExposureMode.AutoExpose;
                    }

                    if (captureDevice.IsWhiteBalanceModeSupported(AVCaptureWhiteBalanceMode.ContinuousAutoWhiteBalance))
                    {
                        captureDevice.WhiteBalanceMode = AVCaptureWhiteBalanceMode.ContinuousAutoWhiteBalance;
                    }
                    else if (captureDevice.IsWhiteBalanceModeSupported(AVCaptureWhiteBalanceMode.AutoWhiteBalance))
                    {
                        captureDevice.WhiteBalanceMode = AVCaptureWhiteBalanceMode.AutoWhiteBalance;
                    }

                    if (UIDevice.CurrentDevice.CheckSystemVersion(7, 0) && captureDevice.AutoFocusRangeRestrictionSupported)
                    {
                        captureDevice.AutoFocusRangeRestriction = AVCaptureAutoFocusRangeRestriction.Near;
                    }

                    if (captureDevice.FocusPointOfInterestSupported)
                    {
                        captureDevice.FocusPointOfInterest = new CGPoint(0.5f, 0.5f);
                    }

                    if (captureDevice.ExposurePointOfInterestSupported)
                    {
                        captureDevice.ExposurePointOfInterest = new CGPoint(0.5f, 0.5f);
                    }

                    captureDevice.UnlockForConfiguration();
                }
                else
                {
                    Console.WriteLine("Failed to Lock for Config: " + err.Description);
                }
            }

            return(true);
        }
Пример #6
0
        public void SurfaceChanged(ISurfaceHolder holder, Format format, int w, int h)
        {
            if (camera == null)
                return;

            var perf = PerformanceCounter.Start ();

            var parameters = camera.GetParameters ();
            parameters.PreviewFormat = ImageFormatType.Nv21;

            var availableResolutions = new List<CameraResolution> ();
            foreach (var sps in parameters.SupportedPreviewSizes) {
                availableResolutions.Add (new CameraResolution {
                    Width = sps.Width,
                    Height = sps.Height
                });
            }

            // Try and get a desired resolution from the options selector
            var resolution = options.GetResolution (availableResolutions);

            // If the user did not specify a resolution, let's try and find a suitable one
            if (resolution == null) {
                // Loop through all supported sizes
                foreach (var sps in parameters.SupportedPreviewSizes) {

                    // Find one that's >= 640x360 but <= 1000x1000
                    // This will likely pick the *smallest* size in that range, which should be fine
                    if (sps.Width >= 640 && sps.Width <= 1000 && sps.Height >= 360 && sps.Height <= 1000) {
                        resolution = new CameraResolution {
                            Width = sps.Width,
                            Height = sps.Height
                        };
                        break;
                    }
                }
            }

            // Google Glass requires this fix to display the camera output correctly
            if (Build.Model.Contains ("Glass")) {
                resolution = new CameraResolution {
                    Width = 640,
                    Height = 360
                };
                // Glass requires 30fps
                parameters.SetPreviewFpsRange (30000, 30000);
            }

            // Hopefully a resolution was selected at some point
            if (resolution != null) {
                Android.Util.Log.Debug(MobileBarcodeScanner.TAG, "Selected Resolution: " + resolution.Width + "x" + resolution.Height);
                parameters.SetPreviewSize (resolution.Width, resolution.Height);
            }

            camera.SetParameters (parameters);

            SetCameraDisplayOrientation (this.activity);

            camera.SetPreviewDisplay (holder);
            camera.StartPreview ();

            //cameraResolution = new Size(parameters.PreviewSize.Width, parameters.PreviewSize.Height);

            PerformanceCounter.Stop (perf, "SurfaceChanged took {0}ms");

            AutoFocus();
        }
        public async Task StartScanningAsync(Action <ZXing.Result> scanCallback, MobileBarcodeScanningOptions options = null)
        {
            if (stopping)
            {
                var error = "Camera is closing";
                OnScannerError?.Invoke(new[] { error });
                return;
            }


            displayRequest.RequestActive();

            isAnalyzing     = true;
            ScanCallback    = scanCallback;
            ScanningOptions = options ?? MobileBarcodeScanningOptions.Default;

            topText.Text    = TopText ?? string.Empty;
            bottomText.Text = BottomText ?? string.Empty;

            if (UseCustomOverlay)
            {
                gridCustomOverlay.Children.Clear();
                if (CustomOverlay != null)
                {
                    gridCustomOverlay.Children.Add(CustomOverlay);
                }

                gridCustomOverlay.Visibility  = Visibility.Visible;
                gridDefaultOverlay.Visibility = Visibility.Collapsed;
            }
            else
            {
                gridCustomOverlay.Visibility  = Visibility.Collapsed;
                gridDefaultOverlay.Visibility = Visibility.Visible;
            }

            // Find which device to use
            var preferredCamera = await GetFilteredCameraOrDefaultAsync(ScanningOptions);

            if (preferredCamera == null)
            {
                var error = "No camera available";
                System.Diagnostics.Debug.WriteLine(error);
                isMediaCaptureInitialized = false;
                OnScannerError?.Invoke(new[] { error });
                return;
            }

            if (preferredCamera.EnclosureLocation == null || preferredCamera.EnclosureLocation.Panel == Windows.Devices.Enumeration.Panel.Unknown)
            {
                // No information on the location of the camera, assume it's an external camera, not integrated on the device.
                externalCamera = true;
            }
            else
            {
                // Camera is fixed on the device.
                externalCamera = false;

                // Only mirror the preview if the camera is on the front panel.
                mirroringPreview = preferredCamera.EnclosureLocation.Panel == Windows.Devices.Enumeration.Panel.Front;
            }

            mediaCapture = new MediaCapture();

            // Initialize the capture with the settings above
            try
            {
                await mediaCapture.InitializeAsync(new MediaCaptureInitializationSettings
                {
                    StreamingCaptureMode = StreamingCaptureMode.Video,
                    VideoDeviceId        = preferredCamera.Id
                });

                isMediaCaptureInitialized = true;
            }
            catch (UnauthorizedAccessException)
            {
                System.Diagnostics.Debug.WriteLine("Denied access to the camera");
            }
            catch (Exception ex)
            {
                System.Diagnostics.Debug.WriteLine("Exception when init MediaCapture: {0}", ex);
            }

            if (!isMediaCaptureInitialized)
            {
                var error = "Unexpected error on Camera initialisation";
                OnScannerError?.Invoke(new[] { error });
                return;
            }


            // Set the capture element's source to show it in the UI
            captureElement.Source        = mediaCapture;
            captureElement.FlowDirection = mirroringPreview ? FlowDirection.RightToLeft : FlowDirection.LeftToRight;

            try
            {
                // Start the preview
                await mediaCapture.StartPreviewAsync();
            }
            catch (Exception ex)
            {
                var error = "Unexpected error on Camera initialisation";
                OnScannerError?.Invoke(new[] { error });
                return;
            }

            if (mediaCapture.CameraStreamState == CameraStreamState.Streaming)
            {
                OnCameraInitialized?.Invoke();
            }

            // Get all the available resolutions for preview
            var availableProperties  = mediaCapture.VideoDeviceController.GetAvailableMediaStreamProperties(MediaStreamType.VideoPreview);
            var availableResolutions = new List <CameraResolution>();

            foreach (var ap in availableProperties)
            {
                var vp = (VideoEncodingProperties)ap;
                System.Diagnostics.Debug.WriteLine("Camera Preview Resolution: {0}x{1}", vp.Width, vp.Height);
                availableResolutions.Add(new CameraResolution {
                    Width = (int)vp.Width, Height = (int)vp.Height
                });
            }
            CameraResolution previewResolution = null;

            if (ScanningOptions.CameraResolutionSelector != null)
            {
                previewResolution = ScanningOptions.CameraResolutionSelector(availableResolutions);
            }

            if (availableResolutions == null || availableResolutions.Count < 1)
            {
                var error = "Camera is busy. Try to close all applications that use camera.";
                OnScannerError?.Invoke(new[] { error });
                return;
            }

            // If the user did not specify a resolution, let's try and find a suitable one
            if (previewResolution == null)
            {
                // Loop through all supported sizes
                foreach (var sps in availableResolutions)
                {
                    // Find one that's >= 640x360 but <= 1000x1000
                    // This will likely pick the *smallest* size in that range, which should be fine
                    if (sps.Width >= 640 && sps.Width <= 1000 && sps.Height >= 360 && sps.Height <= 1000)
                    {
                        previewResolution = new CameraResolution
                        {
                            Width  = sps.Width,
                            Height = sps.Height
                        };
                        break;
                    }
                }
            }

            if (previewResolution == null)
            {
                previewResolution = availableResolutions.LastOrDefault();
            }

            if (previewResolution == null)
            {
                System.Diagnostics.Debug.WriteLine("No preview resolution available. Camera may be in use by another application.");
                return;
            }

            MobileBarcodeScanner.Log("Using Preview Resolution: {0}x{1}", previewResolution.Width, previewResolution.Height);

            // Find the matching property based on the selection, again
            var chosenProp = availableProperties.FirstOrDefault(ap => ((VideoEncodingProperties)ap).Width == previewResolution.Width && ((VideoEncodingProperties)ap).Height == previewResolution.Height);

            // Pass in the requested preview size properties
            // so we can set them at the same time as the preview rotation
            // to save an additional set property call
            await SetPreviewRotationAsync(chosenProp);

            // *after* the preview is setup, set this so that the UI layout happens
            // otherwise the preview gets stuck in a funny place on screen
            captureElement.Stretch = Stretch.UniformToFill;

            await SetupAutoFocus();

            var zxing = ScanningOptions.BuildBarcodeReader();

            timerPreview = new Timer(async(state) =>
            {
                var delay = ScanningOptions.DelayBetweenAnalyzingFrames;

                if (stopping || processing || !isAnalyzing ||
                    (mediaCapture == null || mediaCapture.CameraStreamState != Windows.Media.Devices.CameraStreamState.Streaming))
                {
                    timerPreview.Change(delay, Timeout.Infinite);
                    return;
                }

                processing = true;

                SoftwareBitmapLuminanceSource luminanceSource = null;

                try
                {
                    // Get preview
                    var frame = await mediaCapture.GetPreviewFrameAsync(videoFrame);

                    // Create our luminance source
                    luminanceSource = new SoftwareBitmapLuminanceSource(frame.SoftwareBitmap);
                }
                catch (Exception ex)
                {
                    MobileBarcodeScanner.Log("GetPreviewFrame Failed: {0}", ex);
                }

                ZXing.Result result = null;

                try
                {
                    // Try decoding the image
                    if (luminanceSource != null)
                    {
                        result = zxing.Decode(luminanceSource);
                    }
                }
                catch (Exception ex)
                {
                    MobileBarcodeScanner.Log("Warning: zxing.Decode Failed: {0}", ex);
                }

                // Check if a result was found
                if (result != null && !string.IsNullOrEmpty(result.Text))
                {
                    if (!ContinuousScanning)
                    {
                        delay = Timeout.Infinite;
                        await Dispatcher.RunAsync(CoreDispatcherPriority.Normal, async() => { await StopScanningAsync(); });
                    }
                    else
                    {
                        delay = ScanningOptions.DelayBetweenContinuousScans;
                    }

                    LastScanResult = result;
                    ScanCallback(result);
                }

                processing = false;

                timerPreview.Change(delay, Timeout.Infinite);
            }, null, ScanningOptions.InitialDelayBeforeAnalyzingFrames, Timeout.Infinite);
        }
Пример #8
0
        public async Task StartScanningAsync(Action <ZXing.Result> scanCallback, MobileBarcodeScanningOptions options = null)
        {
            if (stopping)
            {
                return;
            }

            isAnalyzing     = true;
            ScanCallback    = scanCallback;
            ScanningOptions = options ?? MobileBarcodeScanningOptions.Default;

            topText.Text    = TopText ?? string.Empty;
            bottomText.Text = BottomText ?? string.Empty;

            if (UseCustomOverlay)
            {
                gridCustomOverlay.Children.Clear();
                if (CustomOverlay != null)
                {
                    gridCustomOverlay.Children.Add(CustomOverlay);
                }

                gridCustomOverlay.Visibility  = Visibility.Visible;
                gridDefaultOverlay.Visibility = Visibility.Collapsed;
            }
            else
            {
                gridCustomOverlay.Visibility  = Visibility.Collapsed;
                gridDefaultOverlay.Visibility = Visibility.Visible;
            }

            // Find which device to use
            var preferredCamera = await this.GetFilteredCameraOrDefaultAsync(ScanningOptions);

            mediaCapture = new MediaCapture();

            // Initialize the capture with the settings above
            await mediaCapture.InitializeAsync(new MediaCaptureInitializationSettings()
            {
                StreamingCaptureMode = StreamingCaptureMode.Video,
                VideoDeviceId        = preferredCamera.Id
            });

            // Set the capture element's source to show it in the UI
            captureElement.Source = mediaCapture;

            // Start the preview
            await mediaCapture.StartPreviewAsync();

            // Get all the available resolutions for preview
            var availableProperties  = mediaCapture.VideoDeviceController.GetAvailableMediaStreamProperties(MediaStreamType.VideoPreview);
            var availableResolutions = new List <CameraResolution>();

            foreach (var ap in availableProperties)
            {
                var vp = (VideoEncodingProperties)ap;
                System.Diagnostics.Debug.WriteLine("Camera Preview Resolution: {0}x{1}", vp.Width, vp.Height);
                availableResolutions.Add(new CameraResolution {
                    Width = (int)vp.Width, Height = (int)vp.Height
                });
            }
            CameraResolution previewResolution = null;

            if (ScanningOptions.CameraResolutionSelector != null)
            {
                previewResolution = ScanningOptions.CameraResolutionSelector(availableResolutions);
            }

            // If the user did not specify a resolution, let's try and find a suitable one
            if (previewResolution == null)
            {
                // Loop through all supported sizes
                foreach (var sps in availableResolutions)
                {
                    // Find one that's >= 640x360 but <= 1000x1000
                    // This will likely pick the *smallest* size in that range, which should be fine
                    if (sps.Width >= 640 && sps.Width <= 1000 && sps.Height >= 360 && sps.Height <= 1000)
                    {
                        previewResolution = new CameraResolution
                        {
                            Width  = sps.Width,
                            Height = sps.Height
                        };
                        break;
                    }
                }
            }

            if (previewResolution == null)
            {
                previewResolution = availableResolutions.LastOrDefault();
            }

            System.Diagnostics.Debug.WriteLine("Using Preview Resolution: {0}x{1}", previewResolution.Width, previewResolution.Height);

            // Find the matching property based on the selection, again
            var chosenProp = availableProperties.FirstOrDefault(ap => ((VideoEncodingProperties)ap).Width == previewResolution.Width && ((VideoEncodingProperties)ap).Height == previewResolution.Height);

            // Set the selected resolution
            await mediaCapture.VideoDeviceController.SetMediaStreamPropertiesAsync(MediaStreamType.VideoPreview, chosenProp);

            await SetPreviewRotationAsync();

            captureElement.Stretch = Stretch.UniformToFill;

            // Get our preview properties
            var previewProperties = mediaCapture.VideoDeviceController.GetMediaStreamProperties(MediaStreamType.VideoPreview) as VideoEncodingProperties;

            // Setup a frame to use as the input settings
            var destFrame = new VideoFrame(Windows.Graphics.Imaging.BitmapPixelFormat.Bgra8, (int)previewProperties.Width, (int)previewProperties.Height);

            var zxing = ScanningOptions.BuildBarcodeReader();

            timerPreview = new Timer(async(state) => {
                var delay = ScanningOptions.DelayBetweenAnalyzingFrames;

                if (stopping || processing || !isAnalyzing ||
                    (mediaCapture == null || mediaCapture.CameraStreamState != Windows.Media.Devices.CameraStreamState.Streaming))
                {
                    timerPreview.Change(delay, Timeout.Infinite);
                    return;
                }

                processing = true;

                SoftwareBitmapLuminanceSource luminanceSource = null;

                try
                {
                    // Get preview
                    var frame = await mediaCapture.GetPreviewFrameAsync(destFrame);

                    // Create our luminance source
                    luminanceSource = new SoftwareBitmapLuminanceSource(frame.SoftwareBitmap);
                } catch (Exception ex)
                {
                    System.Diagnostics.Debug.WriteLine("GetPreviewFrame Failed: {0}", ex);
                }

                ZXing.Result result = null;

                try
                {
                    // Try decoding the image
                    if (luminanceSource != null)
                    {
                        result = zxing.Decode(luminanceSource);
                    }
                }
                catch (Exception ex)
                {
                }

                // Check if a result was found
                if (result != null && !string.IsNullOrEmpty(result.Text))
                {
                    if (!ContinuousScanning)
                    {
                        delay = Timeout.Infinite;
                        await Dispatcher.RunAsync(CoreDispatcherPriority.Normal, async() => { await StopScanningAsync(); });
                    }
                    else
                    {
                        delay = ScanningOptions.DelayBetweenContinuousScans;
                    }

                    LastScanResult = result;
                    ScanCallback(result);
                }

                processing = false;

                timerPreview.Change(delay, Timeout.Infinite);
            }, null, ScanningOptions.InitialDelayBeforeAnalyzingFrames, Timeout.Infinite);
        }
Пример #9
0
        public void SurfaceChanged(ISurfaceHolder holder, Format format, int w, int h)
        {
            if (camera == null)
            {
                return;
            }

            var perf = PerformanceCounter.Start();

            var parameters = camera.GetParameters();

            parameters.PreviewFormat = ImageFormatType.Nv21;


            var availableResolutions = new List <CameraResolution> ();

            foreach (var sps in parameters.SupportedPreviewSizes)
            {
                availableResolutions.Add(new CameraResolution {
                    Width  = sps.Width,
                    Height = sps.Height
                });
            }

            // Try and get a desired resolution from the options selector
            var resolution = options.GetResolution(availableResolutions);

            // If the user did not specify a resolution, let's try and find a suitable one
            if (resolution == null)
            {
                // Loop through all supported sizes
                foreach (var sps in parameters.SupportedPreviewSizes)
                {
                    // Find one that's >= 640x360 but <= 1000x1000
                    // This will likely pick the *smallest* size in that range, which should be fine
                    if (sps.Width >= 640 && sps.Width <= 1000 && sps.Height >= 360 && sps.Height <= 1000)
                    {
                        resolution = new CameraResolution {
                            Width  = sps.Width,
                            Height = sps.Height
                        };
                        break;
                    }
                }
            }

            // Google Glass requires this fix to display the camera output correctly
            if (Build.Model.Contains("Glass"))
            {
                resolution = new CameraResolution {
                    Width  = 640,
                    Height = 360
                };
                // Glass requires 30fps
                parameters.SetPreviewFpsRange(30000, 30000);
            }

            // Hopefully a resolution was selected at some point
            if (resolution != null)
            {
                Android.Util.Log.Debug(MobileBarcodeScanner.TAG, "Selected Resolution: " + resolution.Width + "x" + resolution.Height);
                parameters.SetPreviewSize(resolution.Width, resolution.Height);
            }

            camera.SetParameters(parameters);

            SetCameraDisplayOrientation(this.activity);

            camera.SetPreviewDisplay(holder);
            camera.StartPreview();

            //cameraResolution = new Size(parameters.PreviewSize.Width, parameters.PreviewSize.Height);

            PerformanceCounter.Stop(perf, "SurfaceChanged took {0}ms");

            AutoFocus();
        }
Пример #10
0
        bool SetupCaptureSession()
        {
            var started = DateTime.UtcNow;

            var availableResolutions = new List <CameraResolution>();

            var consideredResolutions = new Dictionary <NSString, CameraResolution> {
                { AVCaptureSession.Preset352x288, new CameraResolution   {
                      Width = 352, Height = 288
                  } },
                { AVCaptureSession.PresetMedium, new CameraResolution    {
                      Width = 480, Height = 360
                  } },                                                                                                          //480x360
                { AVCaptureSession.Preset640x480, new CameraResolution   {
                      Width = 640, Height = 480
                  } },
                { AVCaptureSession.Preset1280x720, new CameraResolution  {
                      Width = 1280, Height = 720
                  } },
                { AVCaptureSession.Preset1920x1080, new CameraResolution {
                      Width = 1920, Height = 1080
                  } }
            };

            // configure the capture session for low resolution, change this if your code
            // can cope with more data or volume
            session = new AVCaptureSession()
            {
                SessionPreset = AVCaptureSession.Preset640x480
            };

            // create a device input and attach it to the session
            var devices = AVCaptureDevice.DevicesWithMediaType(AVMediaType.Video);

            foreach (var device in devices)
            {
                captureDevice = device;
                if (ScanningOptions.UseFrontCameraIfAvailable.HasValue &&
                    ScanningOptions.UseFrontCameraIfAvailable.Value &&
                    device.Position == AVCaptureDevicePosition.Front)
                {
                    break;                     //Front camera successfully set
                }
                else if (device.Position == AVCaptureDevicePosition.Back && (!ScanningOptions.UseFrontCameraIfAvailable.HasValue || !ScanningOptions.UseFrontCameraIfAvailable.Value))
                {
                    break;                     //Back camera succesfully set
                }
            }
            if (captureDevice == null)
            {
                Console.WriteLine("No captureDevice - this won't work on the simulator, try a physical device");
                if (overlayView != null)
                {
                    AddSubview(overlayView);
                    BringSubviewToFront(overlayView);
                }
                return(false);
            }

            CameraResolution resolution = null;

            // Find resolution
            // Go through the resolutions we can even consider
            foreach (var cr in consideredResolutions)
            {
                // Now check to make sure our selected device supports the resolution
                // so we can add it to the list to pick from
                if (captureDevice.SupportsAVCaptureSessionPreset(cr.Key))
                {
                    availableResolutions.Add(cr.Value);
                }
            }

            resolution = ScanningOptions.GetResolution(availableResolutions);

            // See if the user selected a resolution
            if (resolution != null)
            {
                // Now get the preset string from the resolution chosen
                var preset = (from c in consideredResolutions
                              where c.Value.Width == resolution.Width &&
                              c.Value.Height == resolution.Height
                              select c.Key).FirstOrDefault();

                // If we found a matching preset, let's set it on the session
                if (!string.IsNullOrEmpty(preset))
                {
                    session.SessionPreset = preset;
                }
            }

            var input = AVCaptureDeviceInput.FromDevice(captureDevice);

            if (input == null)
            {
                Console.WriteLine("No input - this won't work on the simulator, try a physical device");
                if (overlayView != null)
                {
                    AddSubview(overlayView);
                    BringSubviewToFront(overlayView);
                }
                return(false);
            }
            else
            {
                session.AddInput(input);
            }


            var startedAVPreviewLayerAlloc = PerformanceCounter.Start();

            previewLayer = new AVCaptureVideoPreviewLayer(session);

            PerformanceCounter.Stop(startedAVPreviewLayerAlloc, "Alloc AVCaptureVideoPreviewLayer took {0} ms.");

            var perf2 = PerformanceCounter.Start();

            previewLayer.VideoGravity = AVLayerVideoGravity.ResizeAspectFill;
            previewLayer.Frame        = new CGRect(0, 0, Frame.Width, Frame.Height);
            previewLayer.Position     = new CGPoint(Layer.Bounds.Width / 2, (Layer.Bounds.Height / 2));

            layerView = new UIView(new CGRect(0, 0, Frame.Width, Frame.Height));
            layerView.AutoresizingMask = UIViewAutoresizing.FlexibleWidth | UIViewAutoresizing.FlexibleHeight;
            layerView.Layer.AddSublayer(previewLayer);

            AddSubview(layerView);

            ResizePreview(UIApplication.SharedApplication.StatusBarOrientation);

            if (overlayView != null)
            {
                AddSubview(overlayView);
                BringSubviewToFront(overlayView);
            }

            PerformanceCounter.Stop(perf2, "PERF: Setting up layers took {0} ms");

            var perf3 = PerformanceCounter.Start();

            session.StartRunning();

            PerformanceCounter.Stop(perf3, "PERF: session.StartRunning() took {0} ms");

            var perf4 = PerformanceCounter.Start();

            var videoSettings = NSDictionary.FromObjectAndKey(new NSNumber((int)CVPixelFormatType.CV32BGRA),
                                                              CVPixelBuffer.PixelFormatTypeKey);

            // create a VideoDataOutput and add it to the sesion
            output = new AVCaptureVideoDataOutput
            {
                WeakVideoSettings = videoSettings
            };

            // configure the output
            queue = new DispatchQueue("ZxingScannerView");             // (Guid.NewGuid().ToString());

            var barcodeReader = ScanningOptions.BuildBarcodeReader();

            outputRecorder = new OutputRecorder(this, img =>
            {
                var ls = img;

                if (!IsAnalyzing)
                {
                    return(false);
                }

                try
                {
                    var perfDecode = PerformanceCounter.Start();

                    if (shouldRotatePreviewBuffer)
                    {
                        ls = ls.rotateCounterClockwise();
                    }

                    var result = barcodeReader.Decode(ls);

                    PerformanceCounter.Stop(perfDecode, "Decode Time: {0} ms");

                    if (result != null)
                    {
                        resultCallback(new ScanResult(result, null));
                        return(true);
                    }
                }
                catch (Exception ex)
                {
                    Console.WriteLine("DECODE FAILED: " + ex);
                }

                return(false);
            });

            output.AlwaysDiscardsLateVideoFrames = true;
            output.SetSampleBufferDelegate(outputRecorder, queue);

            PerformanceCounter.Stop(perf4, "PERF: SetupCamera Finished.  Took {0} ms.");

            session.AddOutput(output);

            var perf5 = PerformanceCounter.Start();

            if (captureDevice.LockForConfiguration(out var err))
            {
                captureDeviceOriginalConfig = new AVConfigs
                {
                    FocusMode                 = captureDevice.FocusMode,
                    ExposureMode              = captureDevice.ExposureMode,
                    WhiteBalanceMode          = captureDevice.WhiteBalanceMode,
                    AutoFocusRangeRestriction = captureDevice.AutoFocusRangeRestriction,
                };

                if (captureDevice.HasFlash)
                {
                    captureDeviceOriginalConfig.FlashMode = captureDevice.FlashMode;
                }
                if (captureDevice.HasTorch)
                {
                    captureDeviceOriginalConfig.TorchMode = captureDevice.TorchMode;
                }
                if (captureDevice.FocusPointOfInterestSupported)
                {
                    captureDeviceOriginalConfig.FocusPointOfInterest = captureDevice.FocusPointOfInterest;
                }
                if (captureDevice.ExposurePointOfInterestSupported)
                {
                    captureDeviceOriginalConfig.ExposurePointOfInterest = captureDevice.ExposurePointOfInterest;
                }

                if (ScanningOptions.DisableAutofocus)
                {
                    captureDevice.FocusMode = AVCaptureFocusMode.Locked;
                }
                else
                {
                    if (captureDevice.IsFocusModeSupported(AVCaptureFocusMode.ContinuousAutoFocus))
                    {
                        captureDevice.FocusMode = AVCaptureFocusMode.ContinuousAutoFocus;
                    }
                    else if (captureDevice.IsFocusModeSupported(AVCaptureFocusMode.AutoFocus))
                    {
                        captureDevice.FocusMode = AVCaptureFocusMode.AutoFocus;
                    }
                }

                if (captureDevice.IsExposureModeSupported(AVCaptureExposureMode.ContinuousAutoExposure))
                {
                    captureDevice.ExposureMode = AVCaptureExposureMode.ContinuousAutoExposure;
                }
                else if (captureDevice.IsExposureModeSupported(AVCaptureExposureMode.AutoExpose))
                {
                    captureDevice.ExposureMode = AVCaptureExposureMode.AutoExpose;
                }

                if (captureDevice.IsWhiteBalanceModeSupported(AVCaptureWhiteBalanceMode.ContinuousAutoWhiteBalance))
                {
                    captureDevice.WhiteBalanceMode = AVCaptureWhiteBalanceMode.ContinuousAutoWhiteBalance;
                }
                else if (captureDevice.IsWhiteBalanceModeSupported(AVCaptureWhiteBalanceMode.AutoWhiteBalance))
                {
                    captureDevice.WhiteBalanceMode = AVCaptureWhiteBalanceMode.AutoWhiteBalance;
                }

                if (UIDevice.CurrentDevice.CheckSystemVersion(7, 0) && captureDevice.AutoFocusRangeRestrictionSupported)
                {
                    captureDevice.AutoFocusRangeRestriction = AVCaptureAutoFocusRangeRestriction.Near;
                }

                if (captureDevice.FocusPointOfInterestSupported)
                {
                    captureDevice.FocusPointOfInterest = new PointF(0.5f, 0.5f);
                }

                if (captureDevice.ExposurePointOfInterestSupported)
                {
                    captureDevice.ExposurePointOfInterest = new PointF(0.5f, 0.5f);
                }

                captureDevice.UnlockForConfiguration();
            }
            else
            {
                Console.WriteLine("Failed to Lock for Config: " + err.Description);
            }

            PerformanceCounter.Stop(perf5, "PERF: Setup Focus in {0} ms.");

            return(true);
        }
        public async Task StartScanningAsync(Action<ZXing.Result> scanCallback, MobileBarcodeScanningOptions options = null)
        {
            if (stopping)
                return;

            displayRequest.RequestActive();

            isAnalyzing = true;
            ScanCallback = scanCallback;
            ScanningOptions = options ?? MobileBarcodeScanningOptions.Default;

            topText.Text = TopText ?? string.Empty;
            bottomText.Text = BottomText ?? string.Empty;

            if (UseCustomOverlay)
            {
                gridCustomOverlay.Children.Clear();
                if (CustomOverlay != null)
                    gridCustomOverlay.Children.Add(CustomOverlay);

                gridCustomOverlay.Visibility = Visibility.Visible;
                gridDefaultOverlay.Visibility = Visibility.Collapsed;
            }
            else
            {
                gridCustomOverlay.Visibility = Visibility.Collapsed;
                gridDefaultOverlay.Visibility = Visibility.Visible;
            }

            // Find which device to use
            var preferredCamera = await GetFilteredCameraOrDefaultAsync(ScanningOptions);
            if (preferredCamera == null)
            {
                System.Diagnostics.Debug.WriteLine("No camera available");
                isMediaCaptureInitialized = false;
                return;
            }

            if (preferredCamera.EnclosureLocation == null || preferredCamera.EnclosureLocation.Panel == Windows.Devices.Enumeration.Panel.Unknown)
            {
                // No information on the location of the camera, assume it's an external camera, not integrated on the device.
                externalCamera = true;
            }
            else
            {
                // Camera is fixed on the device.
                externalCamera = false;

                // Only mirror the preview if the camera is on the front panel.
                mirroringPreview = preferredCamera.EnclosureLocation.Panel == Windows.Devices.Enumeration.Panel.Front;
            }

            mediaCapture = new MediaCapture();

            // Initialize the capture with the settings above
            try
            {
                await mediaCapture.InitializeAsync(new MediaCaptureInitializationSettings
                {
                    StreamingCaptureMode = StreamingCaptureMode.Video,
                    VideoDeviceId = preferredCamera.Id
                });
                isMediaCaptureInitialized = true;
            }
            catch (UnauthorizedAccessException)
            {
                System.Diagnostics.Debug.WriteLine("Denied access to the camera");
            }
            catch (Exception ex)
            {
                System.Diagnostics.Debug.WriteLine("Exception when init MediaCapture: {0}", ex);
            }

            if (!isMediaCaptureInitialized)
                return;

            // Set the capture element's source to show it in the UI
            captureElement.Source = mediaCapture;

            // Start the preview
            await mediaCapture.StartPreviewAsync();


            // Get all the available resolutions for preview
            var availableProperties = mediaCapture.VideoDeviceController.GetAvailableMediaStreamProperties(MediaStreamType.VideoPreview);
            var availableResolutions = new List<CameraResolution>();
            foreach (var ap in availableProperties)
            {
                var vp = (VideoEncodingProperties)ap;
                System.Diagnostics.Debug.WriteLine("Camera Preview Resolution: {0}x{1}", vp.Width, vp.Height);
                availableResolutions.Add(new CameraResolution { Width = (int)vp.Width, Height = (int)vp.Height });                
            }
            CameraResolution previewResolution = null;
            if (ScanningOptions.CameraResolutionSelector != null)
                previewResolution = ScanningOptions.CameraResolutionSelector(availableResolutions);

            // If the user did not specify a resolution, let's try and find a suitable one
            if (previewResolution == null)
            {
                // Loop through all supported sizes
                foreach (var sps in availableResolutions)
                {
                    // Find one that's >= 640x360 but <= 1000x1000
                    // This will likely pick the *smallest* size in that range, which should be fine
                    if (sps.Width >= 640 && sps.Width <= 1000 && sps.Height >= 360 && sps.Height <= 1000)
                    {
                        previewResolution = new CameraResolution
                        {
                            Width = sps.Width,
                            Height = sps.Height
                        };
                        break;
                    }
                }
            }

            if (previewResolution == null)
                previewResolution = availableResolutions.LastOrDefault();

            MobileBarcodeScanner.Log("Using Preview Resolution: {0}x{1}", previewResolution.Width, previewResolution.Height);

            // Find the matching property based on the selection, again
            var chosenProp = availableProperties.FirstOrDefault(ap => ((VideoEncodingProperties)ap).Width == previewResolution.Width && ((VideoEncodingProperties)ap).Height == previewResolution.Height);

            // Pass in the requested preview size properties
            // so we can set them at the same time as the preview rotation
            // to save an additional set property call
            await SetPreviewRotationAsync(chosenProp);
            
            // *after* the preview is setup, set this so that the UI layout happens
            // otherwise the preview gets stuck in a funny place on screen
            captureElement.Stretch = Stretch.UniformToFill;
            
            await SetupAutoFocus();
                        
            var zxing = ScanningOptions.BuildBarcodeReader();

            timerPreview = new Timer(async (state) => {

                var delay = ScanningOptions.DelayBetweenAnalyzingFrames;

                if (stopping || processing || !isAnalyzing
                || (mediaCapture == null || mediaCapture.CameraStreamState != Windows.Media.Devices.CameraStreamState.Streaming))
                {
                    timerPreview.Change(delay, Timeout.Infinite);
                    return;
                }

                processing = true;

                SoftwareBitmapLuminanceSource luminanceSource = null;

                try
                {
                    // Get preview 
                    var frame = await mediaCapture.GetPreviewFrameAsync(videoFrame);

                    // Create our luminance source
                    luminanceSource = new SoftwareBitmapLuminanceSource(frame.SoftwareBitmap);

                } catch (Exception ex)
                {
                    MobileBarcodeScanner.Log ("GetPreviewFrame Failed: {0}", ex);
                }

                ZXing.Result result = null;

                try
                {
                    // Try decoding the image
                    if (luminanceSource != null)
                        result = zxing.Decode(luminanceSource);
                }
                catch (Exception ex)
                {
                    MobileBarcodeScanner.Log("Warning: zxing.Decode Failed: {0}", ex);
                }

                // Check if a result was found
                if (result != null && !string.IsNullOrEmpty (result.Text))
                {
                    if (!ContinuousScanning)
                    {
                        delay = Timeout.Infinite;
                        await Dispatcher.RunAsync(CoreDispatcherPriority.Normal, async () => { await StopScanningAsync(); });
                    }
                    else
                    {
                        delay = ScanningOptions.DelayBetweenContinuousScans;
                    }

                    LastScanResult = result;
                    ScanCallback(result);
                }

                processing = false;

                timerPreview.Change(delay, Timeout.Infinite);
                         
            }, null, ScanningOptions.InitialDelayBeforeAnalyzingFrames, Timeout.Infinite);
        }
Пример #12
0
        public async Task StartScanningAsync (Action<Result> scanResultCallback, MobileBarcodeScanningOptions options = null)
        {
            this.callback = scanResultCallback;
            this.scanningOptions = options ?? MobileBarcodeScanningOptions.Default;

            lastPreviewAnalysis = DateTime.UtcNow.AddMilliseconds (this.scanningOptions.InitialDelayBeforeAnalyzingFrames);
            isAnalyzing = true;

            Console.WriteLine ("StartScanning");

            CheckCameraPermissions ();

            var perf = PerformanceCounter.Start ();

            GetExclusiveAccess ();

            try {
                var version = Build.VERSION.SdkInt;

                if (version >= BuildVersionCodes.Gingerbread) {
                    Android.Util.Log.Debug (MobileBarcodeScanner.TAG, "Checking Number of cameras...");

                    var numCameras = Camera.NumberOfCameras;
                    var camInfo = new Camera.CameraInfo ();
                    var found = false;
                    Android.Util.Log.Debug (MobileBarcodeScanner.TAG, "Found " + numCameras + " cameras...");

                    var whichCamera = CameraFacing.Back;

                    if (this.scanningOptions.UseFrontCameraIfAvailable.HasValue && this.scanningOptions.UseFrontCameraIfAvailable.Value)
                        whichCamera = CameraFacing.Front;

                    for (int i = 0; i < numCameras; i++) {
                        Camera.GetCameraInfo (i, camInfo);
                        if (camInfo.Facing == whichCamera) {
                            Android.Util.Log.Debug (MobileBarcodeScanner.TAG, "Found " + whichCamera + " Camera, opening...");
                            camera = Camera.Open (i);
                            cameraId = i;
                            found = true;
                            break;
                        }
                    }

                    if (!found) {
                        Android.Util.Log.Debug (MobileBarcodeScanner.TAG, "Finding " + whichCamera + " camera failed, opening camera 0...");
                        camera = Camera.Open (0);
                        cameraId = 0;
                    }
                } else {
                    camera = Camera.Open ();
                }

                if (camera == null)
                    Android.Util.Log.Debug (MobileBarcodeScanner.TAG, "Camera is null :(");

                camera.SetPreviewCallback (this);

            } catch (Exception ex) {
                ShutdownCamera ();

                Console.WriteLine ("Setup Error: " + ex);
            }

            PerformanceCounter.Stop (perf, "Camera took {0}ms");

            if (!surfaceChanged)
                await waitSurface.WaitAsync ();
            
            if (camera == null)
                return;

            perf = PerformanceCounter.Start ();

            var parameters = camera.GetParameters ();
            parameters.PreviewFormat = ImageFormatType.Nv21;


            var availableResolutions = new List<CameraResolution> ();
            foreach (var sps in parameters.SupportedPreviewSizes) {
                availableResolutions.Add (new CameraResolution {
                    Width = sps.Width,
                    Height = sps.Height
                });
            }

            // Try and get a desired resolution from the options selector
            var resolution = scanningOptions.GetResolution (availableResolutions);

            // If the user did not specify a resolution, let's try and find a suitable one
            if (resolution == null) {
                // Loop through all supported sizes
                foreach (var sps in parameters.SupportedPreviewSizes) {

                    // Find one that's >= 640x360 but <= 1000x1000
                    // This will likely pick the *smallest* size in that range, which should be fine
                    if (sps.Width >= 640 && sps.Width <= 1000 && sps.Height >= 360 && sps.Height <= 1000) {
                        resolution = new CameraResolution {
                            Width = sps.Width,
                            Height = sps.Height
                        };
                        break;
                    }
                }
            }

            // Google Glass requires this fix to display the camera output correctly
            if (Build.Model.Contains ("Glass")) {
                resolution = new CameraResolution {
                    Width = 640,
                    Height = 360
                };
                // Glass requires 30fps
                parameters.SetPreviewFpsRange (30000, 30000);
            }

            // Hopefully a resolution was selected at some point
            if (resolution != null) {
                Android.Util.Log.Debug (MobileBarcodeScanner.TAG, "Selected Resolution: " + resolution.Width + "x" + resolution.Height);
                parameters.SetPreviewSize (resolution.Width, resolution.Height);
            }

            camera.SetParameters (parameters);

            SetCameraDisplayOrientation (this.activity);

            camera.SetPreviewDisplay (this.Holder);
            camera.StartPreview ();

            PerformanceCounter.Stop (perf, "SurfaceChanged took {0}ms");

            AutoFocus ();

        }
        async Task SetupCamera()
        {
            if (camera != null)
            {
                return;
            }

            await tcsSurfaceReady.Task;

            lastPreviewAnalysis = DateTime.UtcNow.AddMilliseconds(this.scanningOptions.InitialDelayBeforeAnalyzingFrames);
            isAnalyzing         = true;

            CheckCameraPermissions();

            var perf = PerformanceCounter.Start();

            GetExclusiveAccess();

            try {
                var version = Build.VERSION.SdkInt;

                if (version >= BuildVersionCodes.Gingerbread)
                {
                    Android.Util.Log.Debug(MobileBarcodeScanner.TAG, "Checking Number of cameras...");

                    var numCameras = Camera.NumberOfCameras;
                    var camInfo    = new Camera.CameraInfo();
                    var found      = false;
                    Android.Util.Log.Debug(MobileBarcodeScanner.TAG, "Found " + numCameras + " cameras...");

                    var whichCamera = CameraFacing.Back;

                    if (this.scanningOptions.UseFrontCameraIfAvailable.HasValue && this.scanningOptions.UseFrontCameraIfAvailable.Value)
                    {
                        whichCamera = CameraFacing.Front;
                    }

                    for (int i = 0; i < numCameras; i++)
                    {
                        Camera.GetCameraInfo(i, camInfo);
                        if (camInfo.Facing == whichCamera)
                        {
                            Android.Util.Log.Debug(MobileBarcodeScanner.TAG, "Found " + whichCamera + " Camera, opening...");
                            camera   = Camera.Open(i);
                            cameraId = i;
                            found    = true;
                            break;
                        }
                    }

                    if (!found)
                    {
                        Android.Util.Log.Debug(MobileBarcodeScanner.TAG, "Finding " + whichCamera + " camera failed, opening camera 0...");
                        camera   = Camera.Open(0);
                        cameraId = 0;
                    }
                }
                else
                {
                    camera = Camera.Open();
                }

                if (camera != null)
                {
                    camera.SetPreviewCallback(this);
                }
                else
                {
                    MobileBarcodeScanner.LogWarn(MobileBarcodeScanner.TAG, "Camera is null :(");
                    return;
                }
            } catch (Exception ex) {
                ShutdownCamera();
                MobileBarcodeScanner.LogError("Setup Error: {0}", ex);
                return;
            }
            PerformanceCounter.Stop(perf, "Setup Camera took {0}ms");

            perf = PerformanceCounter.Start();

            var parameters = camera.GetParameters();

            parameters.PreviewFormat = ImageFormatType.Nv21;

            // First try continuous video, then auto focus, then fixed
            var supportedFocusModes = parameters.SupportedFocusModes;

            if (Build.VERSION.SdkInt >= BuildVersionCodes.IceCreamSandwich &&
                supportedFocusModes.Contains(Camera.Parameters.FocusModeContinuousPicture))
            {
                parameters.FocusMode = Camera.Parameters.FocusModeContinuousPicture;
            }
            else if (supportedFocusModes.Contains(Camera.Parameters.FocusModeContinuousVideo))
            {
                parameters.FocusMode = Camera.Parameters.FocusModeContinuousVideo;
            }
            else if (supportedFocusModes.Contains(Camera.Parameters.FocusModeAuto))
            {
                parameters.FocusMode = Camera.Parameters.FocusModeAuto;
            }
            else if (supportedFocusModes.Contains(Camera.Parameters.FocusModeFixed))
            {
                parameters.FocusMode = Camera.Parameters.FocusModeFixed;
            }

            var selectedFps = parameters.SupportedPreviewFpsRange.FirstOrDefault();

            if (selectedFps != null)
            {
                // This will make sure we select a range with the lowest minimum FPS
                // and maximum FPS which still has the lowest minimum
                // This should help maximize performance / support for hardware
                foreach (var fpsRange in parameters.SupportedPreviewFpsRange)
                {
                    if (fpsRange [0] <= selectedFps [0] &&
                        fpsRange [1] > selectedFps [1])
                    {
                        selectedFps = fpsRange;
                    }
                }
                parameters.SetPreviewFpsRange(selectedFps [0], selectedFps [1]);
            }

            var availableResolutions = new List <CameraResolution> ();

            foreach (var sps in parameters.SupportedPreviewSizes)
            {
                availableResolutions.Add(new CameraResolution {
                    Width  = sps.Width,
                    Height = sps.Height
                });
            }

            // Try and get a desired resolution from the options selector
            var resolution = scanningOptions.GetResolution(availableResolutions);

            // If the user did not specify a resolution, let's try and find a suitable one
            if (resolution == null)
            {
                // Loop through all supported sizes
                foreach (var sps in parameters.SupportedPreviewSizes)
                {
                    // Find one that's >= 640x360 but <= 1000x1000
                    // This will likely pick the *smallest* size in that range, which should be fine
                    if (sps.Width >= 640 && sps.Width <= 1000 && sps.Height >= 360 && sps.Height <= 1000)
                    {
                        resolution = new CameraResolution {
                            Width  = sps.Width,
                            Height = sps.Height
                        };
                        break;
                    }
                }
            }

            // Google Glass requires this fix to display the camera output correctly
            if (Build.Model.Contains("Glass"))
            {
                resolution = new CameraResolution {
                    Width  = 640,
                    Height = 360
                };
                // Glass requires 30fps
                parameters.SetPreviewFpsRange(30000, 30000);
            }

            // Hopefully a resolution was selected at some point
            if (resolution != null)
            {
                Android.Util.Log.Debug(MobileBarcodeScanner.TAG, "Selected Resolution: " + resolution.Width + "x" + resolution.Height);
                parameters.SetPreviewSize(resolution.Width, resolution.Height);
            }

            camera.SetParameters(parameters);

            SetCameraDisplayOrientation(this.activity);

            camera.SetPreviewDisplay(this.Holder);
            camera.StartPreview();

            PerformanceCounter.Stop(perf, "Setup Camera Parameters took {0}ms");

            // Docs suggest if Auto or Macro modes, we should invoke AutoFocus at least once
            var currentFocusMode = camera.GetParameters().FocusMode;

            if (currentFocusMode == Camera.Parameters.FocusModeAuto ||
                currentFocusMode == Camera.Parameters.FocusModeMacro)
            {
                AutoFocus();
            }
        }
        async Task SetupCamera ()
        {
            if (camera != null)
                return;

            await tcsSurfaceReady.Task;
            
            lastPreviewAnalysis = DateTime.UtcNow.AddMilliseconds (this.scanningOptions.InitialDelayBeforeAnalyzingFrames);
            isAnalyzing = true;

            CheckCameraPermissions ();

            var perf = PerformanceCounter.Start ();

            GetExclusiveAccess ();

            try {
                var version = Build.VERSION.SdkInt;

                if (version >= BuildVersionCodes.Gingerbread) {
                    Android.Util.Log.Debug (MobileBarcodeScanner.TAG, "Checking Number of cameras...");

                    var numCameras = Camera.NumberOfCameras;
                    var camInfo = new Camera.CameraInfo ();
                    var found = false;
                    Android.Util.Log.Debug (MobileBarcodeScanner.TAG, "Found " + numCameras + " cameras...");

                    var whichCamera = CameraFacing.Back;

                    if (this.scanningOptions.UseFrontCameraIfAvailable.HasValue && this.scanningOptions.UseFrontCameraIfAvailable.Value)
                        whichCamera = CameraFacing.Front;

                    for (int i = 0; i < numCameras; i++) {
                        Camera.GetCameraInfo (i, camInfo);
                        if (camInfo.Facing == whichCamera) {
                            Android.Util.Log.Debug (MobileBarcodeScanner.TAG, "Found " + whichCamera + " Camera, opening...");
                            camera = Camera.Open (i);
                            cameraId = i;
                            found = true;
                            break;
                        }
                    }

                    if (!found) {
                        Android.Util.Log.Debug (MobileBarcodeScanner.TAG, "Finding " + whichCamera + " camera failed, opening camera 0...");
                        camera = Camera.Open (0);
                        cameraId = 0;
                    }
                } else {
                    camera = Camera.Open ();
                }

                if (camera != null)
                    camera.SetPreviewCallback (this);
                else {
                    MobileBarcodeScanner.LogWarn (MobileBarcodeScanner.TAG, "Camera is null :(");
                    return;
                }
                
            } catch (Exception ex) {
                ShutdownCamera ();
                MobileBarcodeScanner.LogError ("Setup Error: {0}", ex);
                return;
            }
            PerformanceCounter.Stop (perf, "Setup Camera took {0}ms");

            perf = PerformanceCounter.Start ();

            var parameters = camera.GetParameters ();
            parameters.PreviewFormat = ImageFormatType.Nv21;

            // First try continuous video, then auto focus, then fixed
            var supportedFocusModes = parameters.SupportedFocusModes;
            if (supportedFocusModes.Contains (Camera.Parameters.FocusModeAuto))
                parameters.FocusMode = Camera.Parameters.FocusModeAuto;
            else if (supportedFocusModes.Contains (Camera.Parameters.FocusModeContinuousVideo))
                parameters.FocusMode = Camera.Parameters.FocusModeContinuousVideo;
            else if (supportedFocusModes.Contains (Camera.Parameters.FocusModeFixed))
                parameters.FocusMode = Camera.Parameters.FocusModeFixed;

            var selectedFps = parameters.SupportedPreviewFpsRange.FirstOrDefault ();
            if (selectedFps != null) {
                // This will make sure we select a range with the lowest minimum FPS
                // and maximum FPS which still has the lowest minimum
                // This should help maximize performance / support for hardware
                foreach (var fpsRange in parameters.SupportedPreviewFpsRange) {
                    if (fpsRange [0] <= selectedFps [0]
                        && fpsRange [1] > selectedFps [1])
                        selectedFps = fpsRange;
                }
                parameters.SetPreviewFpsRange (selectedFps [0], selectedFps [1]);
            }

            var availableResolutions = new List<CameraResolution> ();
            foreach (var sps in parameters.SupportedPreviewSizes) {
                availableResolutions.Add (new CameraResolution {
                    Width = sps.Width,
                    Height = sps.Height
                });
            }

            // Try and get a desired resolution from the options selector
            var resolution = scanningOptions.GetResolution (availableResolutions);

            // If the user did not specify a resolution, let's try and find a suitable one
            if (resolution == null) {
                // Loop through all supported sizes
                foreach (var sps in parameters.SupportedPreviewSizes) {

                    // Find one that's >= 640x360 but <= 1000x1000
                    // This will likely pick the *smallest* size in that range, which should be fine
                    if (sps.Width >= 640 && sps.Width <= 1000 && sps.Height >= 360 && sps.Height <= 1000) {
                        resolution = new CameraResolution {
                            Width = sps.Width,
                            Height = sps.Height
                        };
                        break;
                    }
                }
            }

            // Google Glass requires this fix to display the camera output correctly
            if (Build.Model.Contains ("Glass")) {
                resolution = new CameraResolution {
                    Width = 640,
                    Height = 360
                };
                // Glass requires 30fps
                parameters.SetPreviewFpsRange (30000, 30000);
            }

            // Hopefully a resolution was selected at some point
            if (resolution != null) {
                Android.Util.Log.Debug (MobileBarcodeScanner.TAG, "Selected Resolution: " + resolution.Width + "x" + resolution.Height);
                parameters.SetPreviewSize (resolution.Width, resolution.Height);
            }

            camera.SetParameters (parameters);

            SetCameraDisplayOrientation (this.activity);

            camera.SetPreviewDisplay (this.Holder);
            camera.StartPreview ();

            PerformanceCounter.Stop (perf, "Setup Camera Parameters took {0}ms");

            // Docs suggest if Auto or Macro modes, we should invoke AutoFocus at least once
            var currentFocusMode = camera.GetParameters ().FocusMode;
            if (currentFocusMode == Camera.Parameters.FocusModeAuto 
               || currentFocusMode == Camera.Parameters.FocusModeMacro)
                AutoFocus ();
        }