private bool InitScanner(BarcodeScanner.BarcodeFormat barcodeType)
{
device = AVCaptureDevice.GetDefaultDevice(AVMediaType.Video);
if (device == null)
{
return(false);
}
input = AVCaptureDeviceInput.FromDevice(device);
if (input.Device.IsFocusModeSupported(AVCaptureFocusMode.ContinuousAutoFocus))
{
input.Device.LockForConfiguration(out NSError err);
input.Device.FocusMode = AVCaptureFocusMode.ContinuousAutoFocus;
input.Device.UnlockForConfiguration();
}
if (input == null)
{
return(false);
}
output = new AVCaptureMetadataOutput();
output.SetDelegate(this, DispatchQueue.MainQueue);
session = new AVCaptureSession();
session.AddInput(input);
session.AddOutput(output);
output.MetadataObjectTypes = GetBarcodeFormat(barcodeType);
captureVideoPreviewLayer = AVCaptureVideoPreviewLayer.FromSession(session);
captureVideoPreviewLayer.Frame = CGRect.Empty;
captureVideoPreviewLayer.VideoGravity = AVLayerVideoGravity.ResizeAspectFill;
captureVideoPreviewLayer.Connection.VideoOrientation = GetDeviceOrientation();
return(true);
}
private bool initScanner()
{
device = AVCaptureDevice.DefaultDeviceWithMediaType(AVMediaType.Video);
if (device == null)
{
this.Debug("AVCaptureDevice is null");
return(false);
}
input = AVCaptureDeviceInput.FromDevice(device);
if (input == null)
{
this.Debug("AVCaptureDeviceInput is null");
return(false);
}
output = new AVCaptureMetadataOutput();
output.SetDelegate(this, DispatchQueue.MainQueue);
session = new AVCaptureSession();
session.AddInput(input);
session.AddOutput(output);
output.MetadataObjectTypes = configuration.Barcodes.ConvertToIOS();
captureVideoPreviewLayer = AVCaptureVideoPreviewLayer.FromSession(session);
captureVideoPreviewLayer.Frame = CGRect.Empty;
captureVideoPreviewLayer.VideoGravity = AVLayerVideoGravity.ResizeAspectFill;
captureVideoPreviewLayer.Connection.VideoOrientation = getDeviceOrientation();
return(true);
}
void SetupCaptureDevice()
{
captureDevice = AVCaptureDevice.GetDefaultDevice(AVMediaTypes.Video);
if (captureDevice == null)
{
Console.WriteLine("Error: no video devices available");
return;
}
videoDeviceInput = AVCaptureDeviceInput.FromDevice(captureDevice);
if (videoDeviceInput == null)
{
Console.WriteLine("Error: could not create AVCaptureDeviceInput");
return;
}
if (captureSession.CanAddInput(videoDeviceInput))
{
captureSession.AddInput(videoDeviceInput);
}
previewLayer = AVCaptureVideoPreviewLayer.FromSession(captureSession);
previewLayer.VideoGravity = AVLayerVideoGravity.ResizeAspect;
previewLayer.Connection.VideoOrientation = AVCaptureVideoOrientation.Portrait;
}
public override void ViewDidLoad()
{
base.ViewDidLoad();
var device = AVCaptureDevice.GetDefaultDevice(AVMediaTypes.Video);
if (device is null)
{
this.ShowAlert("无法访问相机", null);
return;
}
var input = AVCaptureDeviceInput.FromDevice(device);
if (input is null)
{
this.ShowAlert("无法访问相机", null);
return;
}
session.AddInput(input);
try
{
var output = new AVCaptureMetadataOutput();
output.SetDelegate(this, DispatchQueue.MainQueue);
session.AddOutput(output);
output.MetadataObjectTypes = AVMetadataObjectType.QRCode;
}
catch
{
return;
}
preview = AVCaptureVideoPreviewLayer.FromSession(session);
if (preview is null)
{
this.ShowAlert("无法显示扫描预览", null);
return;
}
preview.VideoGravity = AVLayerVideoGravity.Resize;
preview.Frame = View.Layer.Bounds;
View.Layer.AddSublayer(preview);
session.StartRunning();
codeFrame = new UIView();
codeFrame.Layer.BorderColor = UIColor.Green.CGColor;
codeFrame.Layer.BorderWidth = 2;
View.AddSubview(codeFrame);
View.BringSubviewToFront(codeFrame);
}
void InitializeCameraLayer()
{
this.captureSession = new AVCaptureSession()
{
SessionPreset = AVCaptureSession.PresetMedium // TODO investigate that
};
var captureDevice = AVCaptureDevice.DevicesWithMediaType(AVMediaType.Video).Where(dev => dev.Position == AVCaptureDevicePosition.Front).FirstOrDefault();
if (captureDevice == null)
{
Console.WriteLine("No captureDevice - this won't work on the simulator, try a physical device");
return;
}
var input = AVCaptureDeviceInput.FromDevice(captureDevice);
if (input == null)
{
Console.WriteLine("No input - this won't work on the simulator, try a physical device");
return;
}
this.captureSession.AddInput(input);
// set up the output
output = new AVCaptureStillImageOutput();
var dict = new NSMutableDictionary();
dict [AVVideo.CodecKey] = new NSNumber((int)AVVideoCodec.JPEG);
captureSession.AddOutput(output);
this.previewLayer = AVCaptureVideoPreviewLayer.FromSession(this.captureSession);
this.previewLayer.LayerVideoGravity = AVLayerVideoGravity.ResizeAspectFill;
this.previewLayer.Frame = this.View.Frame;
this.captureSession.StartRunning();
this.cameraInitialized = true;
}
void setupCaptureSession()
{
//Create a device for capturing Barcodes
var captureDevice = AVCaptureDevice.GetDefaultDevice(AVMediaTypes.Video);
//Configure the dvice for something fancy autofocus stuffs
ConfigureCameraForDevice(captureDevice);
//Create an input from that device - meaning to instaniate the device to make an input node... err something like that
var captureInput = AVCaptureDeviceInput.FromDevice(captureDevice);
//Add the input to the session
session.AddInput(captureInput);
//Create a preview layer for the view
var previewLayer = AVCaptureVideoPreviewLayer.FromSession(session);
previewLayer.VideoGravity = AVLayerVideoGravity.ResizeAspectFill;
previewLayer.Frame = vie_Preview_cam.Frame;
//Add the preview layer to the View for the camera uiview
vie_Preview_cam.Layer.AddSublayer(previewLayer);
//Assign who's going to handle the metadataoutput
var metadataoutput = new AVCaptureMetadataOutput();
//Set delegate
metadataoutput.SetDelegate(this, CoreFoundation.DispatchQueue.MainQueue);
//Add the metadataoutput to session
session.AddOutput(metadataoutput);
//Assign which type of Codes will be read,
metadataoutput.MetadataObjectTypes = AVMetadataObjectType.QRCode;
//Start the Session
session.StartRunning();
}
public override void ViewDidLoad()
{
base.ViewDidLoad();
this.View.BackgroundColor = UIColor.White;
NSError error;
// Setup detector options.
var options = new CIDetectorOptions {
Accuracy = FaceDetectorAccuracy.High,
// Can give a hint here about the rects to detect. 1.4 would be for A4 sheets of paper for instance.
AspectRatio = 1.41f,
};
// Create a rectangle detector. Note that you can also create QR detector or a face detector.
// Most of this code will also work with other detectors (like streaming to a preview layer and grabbing images).
this.detector = CIDetector.CreateRectangleDetector(context: null, detectorOptions: options);
// Create the session. The AVCaptureSession is the managing instance of the whole video handling.
var captureSession = new AVCaptureSession()
{
// Defines what quality we want to use for the images we grab. Photo gives highest resolutions.
SessionPreset = AVCaptureSession.PresetPhoto
};
// Find a suitable AVCaptureDevice for video input.
var device = AVCaptureDevice.DefaultDeviceWithMediaType(AVMediaType.Video);
if (device == null)
{
// This will not work on the iOS Simulator - there is no camera. :-)
throw new InvalidProgramException("Failed to get AVCaptureDevice for video input!");
}
// Create a device input with the device and add it to the session.
var videoInput = AVCaptureDeviceInput.FromDevice(device, out error);
if (videoInput == null)
{
throw new InvalidProgramException("Failed to get AVCaptureDeviceInput from AVCaptureDevice!");
}
// Let session read from the input, this is our source.
captureSession.AddInput(videoInput);
// Create output for the video stream. This is the destination.
var videoOutput = new AVCaptureVideoDataOutput()
{
AlwaysDiscardsLateVideoFrames = true
};
// Define the video format we want to use. Note that Xamarin exposes the CompressedVideoSetting and UncompressedVideoSetting
// properties on AVCaptureVideoDataOutput un Unified API, but I could not get these to work. The VideoSettings property is deprecated,
// so I use the WeakVideoSettings instead which takes an NSDictionary as input.
this.videoSettingsDict = new NSMutableDictionary();
this.videoSettingsDict.Add(CVPixelBuffer.PixelFormatTypeKey, NSNumber.FromUInt32((uint)CVPixelFormatType.CV32BGRA));
videoOutput.WeakVideoSettings = this.videoSettingsDict;
// Create a delegate to report back to us when an image has been captured.
// We want to grab the camera stream and feed it through a AVCaptureVideoDataOutputSampleBufferDelegate
// which allows us to get notified if a new image is availeble. An implementation of that delegate is VideoFrameSampleDelegate in this project.
this.sampleBufferDelegate = new VideoFrameSamplerDelegate();
// Processing happens via Grand Central Dispatch (GCD), so we need to provide a queue.
// This is pretty much like a system managed thread (see: http://zeroheroblog.com/ios/concurrency-in-ios-grand-central-dispatch-gcd-dispatch-queues).
this.sessionQueue = new DispatchQueue("AVSessionQueue");
// Assign the queue and the delegate to the output. Now all output will go through the delegate.
videoOutput.SetSampleBufferDelegate(this.sampleBufferDelegate, this.sessionQueue);
// Add output to session.
captureSession.AddOutput(videoOutput);
// We also want to visualize the input stream. The raw stream can be fed into an AVCaptureVideoPreviewLayer, which is a subclass of CALayer.
// A CALayer can be added to a UIView. We add that layer to the controller's main view.
var layer = this.View.Layer;
this.videoLayer = AVCaptureVideoPreviewLayer.FromSession(captureSession);
this.videoLayer.Frame = layer.Bounds;
layer.AddSublayer(this.videoLayer);
// All setup! Start capturing!
captureSession.StartRunning();
// This is just for information and allows you to get valid values for the detection framerate.
Console.WriteLine("Available capture framerates:");
var rateRanges = device.ActiveFormat.VideoSupportedFrameRateRanges;
foreach (var r in rateRanges)
{
Console.WriteLine(r.MinFrameRate + "; " + r.MaxFrameRate + "; " + r.MinFrameDuration + "; " + r.MaxFrameDuration);
}
// Configure framerate. Kind of weird way of doing it but the only one that works.
device.LockForConfiguration(out error);
// CMTime constructor means: 1 = one second, DETECTION_FPS = how many samples per unit, which is 1 second in this case.
device.ActiveVideoMinFrameDuration = new CMTime(1, DETECTION_FPS);
device.ActiveVideoMaxFrameDuration = new CMTime(1, DETECTION_FPS);
device.UnlockForConfiguration();
// Put a small image view at the top left that shows the live image with the detected rectangle(s).
this.imageViewOverlay = new UIImageView
{
ContentMode = UIViewContentMode.ScaleAspectFit,
BackgroundColor = UIColor.Gray
};
this.imageViewOverlay.Layer.BorderColor = UIColor.Red.CGColor;
this.imageViewOverlay.Layer.BorderWidth = 3f;
this.Add(this.imageViewOverlay);
// Put another image view top right that shows the image with perspective correction.
this.imageViewPerspective = new UIImageView
{
ContentMode = UIViewContentMode.ScaleAspectFit,
BackgroundColor = UIColor.Gray
};
this.imageViewPerspective.Layer.BorderColor = UIColor.Red.CGColor;
this.imageViewPerspective.Layer.BorderWidth = 3f;
this.Add(this.imageViewPerspective);
// Add some lables for information.
this.mainWindowLbl = new UILabel
{
Text = "Live stream from camera. Point camera to a rectangular object.",
TextAlignment = UITextAlignment.Center
};
this.Add(this.mainWindowLbl);
this.detectionWindowLbl = new UILabel
{
Text = "Detected rectangle overlay",
TextAlignment = UITextAlignment.Center
};
this.Add(this.detectionWindowLbl);
this.perspectiveWindowLbl = new UILabel
{
Text = "Perspective corrected",
TextAlignment = UITextAlignment.Center
};
this.Add(this.perspectiveWindowLbl);
}
/// <summary>
/// 스캐너를 초기화합니다.
/// </summary>
/// <param name="barcodeFormat">인식할 바코드 포멧</param>
/// <param name="sessionPreset">해상도</param>
/// <returns></returns>
private bool InitScanner(AVMetadataObjectType barcodeFormat, NSString sessionPreset)
{
// 카메라 접근 권한 확인
if (!IsCameraAuthorized)
{
this.Write("카메라 사용이 허용되지 않습니다.");
return(false);
}
// 후면 카메라를 캡처할 장치로 설정
Device = AVCaptureDevice
.DevicesWithMediaType(AVMediaType.Video)
.FirstOrDefault(e => e.Position == AVCaptureDevicePosition.Back);
if (Device == null)
{
this.Write("후면 카메라가 없습니다.");
return(false);
}
// 입력 설정
Input = AVCaptureDeviceInput.FromDevice(Device);
if (Input == null)
{
this.Write("AVCaptureDeviceInput이 null 입니다.");
return(false);
}
// 출력 설정
CaptureDelegate = new CaptureDelegate((metadataObjects) =>
{
if (BarcodeDetected == null)
{
return;
}
foreach (var metadata in metadataObjects)
{
var data = ((AVMetadataMachineReadableCodeObject)metadata).StringValue;
BarcodeDetected?.Invoke(new BarcodeData(metadata.Type.ToTmonFormat(), data));
}
});
Output = new AVCaptureMetadataOutput();
Output.SetDelegate(CaptureDelegate, DispatchQueue.MainQueue);
// 세션 설정
Session = new AVCaptureSession()
{
SessionPreset = sessionPreset,
};
Session.AddInput(Input);
Session.AddOutput(Output);
// 검출할 바코드 포멧 설정(중요 : 반드시 세션 설정 뒤에 와야함)
Output.MetadataObjectTypes = barcodeFormat;
// 프리뷰어 설정
Previewer = AVCaptureVideoPreviewLayer.FromSession(Session);
Previewer.Frame = CGRect.Empty;
Previewer.VideoGravity = AVLayerVideoGravity.ResizeAspectFill;
Previewer.Connection.VideoOrientation = DeviceOrientation;
return(true);
}
protected virtual void SetupAVCapture()
{
AVCaptureDeviceInput deviceInput;
// Select a video device, make an input
var videoDevice = AVCaptureDeviceDiscoverySession.Create(
new AVCaptureDeviceType[] { AVCaptureDeviceType.BuiltInWideAngleCamera },
AVMediaType.Video,
AVCaptureDevicePosition.Back
).Devices.FirstOrDefault();
deviceInput = new AVCaptureDeviceInput(videoDevice, out NSError error);
if (error != null)
{
Console.WriteLine($"Could not create video device input: {error.LocalizedDescription}");
return;
}
session.BeginConfiguration();
session.SessionPreset = AVCaptureSession.Preset640x480; // Model image size is smaller
// Add a video input
if (!session.CanAddInput(deviceInput))
{
Console.WriteLine("Could not add video device input to the session");
session.CommitConfiguration();
return;
}
session.AddInput(deviceInput);
if (session.CanAddOutput(videoDataOutput))
{
session.AddOutput(videoDataOutput);
// Add a video data ouptut
videoDataOutput.AlwaysDiscardsLateVideoFrames = true;
videoDataOutput.WeakVideoSettings = new NSDictionary(CVPixelBuffer.PixelFormatTypeKey, CVPixelFormatType.CV420YpCbCr8BiPlanarFullRange);
videoDataOutput.SetSampleBufferDelegateQueue(this, videoDataOutputQueue);
}
else
{
Console.WriteLine("Could not add video data output to the session");
session.CommitConfiguration();
return;
}
var captureConnection = videoDataOutput.ConnectionFromMediaType(AVMediaType.Video);
// Always process the frames
captureConnection.Enabled = true;
videoDevice.LockForConfiguration(out NSError error2);
if (error2 == null)
{
var formatDescription = videoDevice.ActiveFormat.FormatDescription as CMVideoFormatDescription;
CMVideoDimensions dimensions = formatDescription.Dimensions;
bufferSize.Width = dimensions.Width;
bufferSize.Height = dimensions.Height;
videoDevice.UnlockForConfiguration();
}
else
{
Console.WriteLine($"{error2.LocalizedDescription}");
}
session.CommitConfiguration();
previewLayer = AVCaptureVideoPreviewLayer.FromSession(session);
previewLayer.VideoGravity = AVLayerVideoGravity.ResizeAspectFill;
rootLayer = previewView.Layer;
previewLayer.Frame = rootLayer.Bounds;
rootLayer.AddSublayer(previewLayer);
}
public override void ViewDidLoad()
{
base.ViewDidLoad();
this.View.BackgroundColor = UIColor.White;
NSError error;
// Create the session. The AVCaptureSession is the managing instance of the whole video handling.
var captureSession = new AVCaptureSession()
{
// Defines what quality we want to use for the images we grab. Photo gives highest resolutions.
SessionPreset = AVCaptureSession.PresetPhoto
};
// Find a suitable AVCaptureDevice for video input.
var device = AVCaptureDevice.GetDefaultDevice(AVMediaType.Video);
if (device == null)
{
// This will not work on the iOS Simulator - there is no camera. :-)
throw new InvalidProgramException("Failed to get AVCaptureDevice for video input!");
}
// Create a device input with the device and add it to the session.
var videoInput = AVCaptureDeviceInput.FromDevice(device, out error);
if (videoInput == null)
{
throw new InvalidProgramException("Failed to get AVCaptureDeviceInput from AVCaptureDevice!");
}
// Let session read from the input, this is our source.
captureSession.AddInput(videoInput);
// Create output for the video stream. This is the destination.
var videoOutput = new AVCaptureVideoDataOutput()
{
AlwaysDiscardsLateVideoFrames = true
};
// Define the video format we want to use. Note that Xamarin exposes the CompressedVideoSetting and UncompressedVideoSetting
// properties on AVCaptureVideoDataOutput un Unified API, but I could not get these to work. The VideoSettings property is deprecated,
// so I use the WeakVideoSettings instead which takes an NSDictionary as input.
this.videoSettingsDict = new NSMutableDictionary();
this.videoSettingsDict.Add(CVPixelBuffer.PixelFormatTypeKey, NSNumber.FromUInt32((uint)CVPixelFormatType.CV32BGRA));
videoOutput.WeakVideoSettings = this.videoSettingsDict;
// Create a delegate to report back to us when an image has been captured.
// We want to grab the camera stream and feed it through a AVCaptureVideoDataOutputSampleBufferDelegate
// which allows us to get notified if a new image is availeble. An implementation of that delegate is VideoFrameSampleDelegate in this project.
this.sampleBufferDelegate = new VideoFrameSamplerDelegate();
// Processing happens via Grand Central Dispatch (GCD), so we need to provide a queue.
// This is pretty much like a system managed thread (see: http://zeroheroblog.com/ios/concurrency-in-ios-grand-central-dispatch-gcd-dispatch-queues).
this.sessionQueue = new DispatchQueue("AVSessionQueue");
// Assign the queue and the delegate to the output. Now all output will go through the delegate.
videoOutput.SetSampleBufferDelegateQueue(this.sampleBufferDelegate, this.sessionQueue);
// Add output to session.
captureSession.AddOutput(videoOutput);
// We also want to visualize the input stream. The raw stream can be fed into an AVCaptureVideoPreviewLayer, which is a subclass of CALayer.
// A CALayer can be added to a UIView. We add that layer to the controller's main view.
var layer = this.View.Layer;
this.videoLayer = AVCaptureVideoPreviewLayer.FromSession(captureSession);
this.videoLayer.Frame = layer.Bounds;
layer.AddSublayer(this.videoLayer);
// All setup! Start capturing!
captureSession.StartRunning();
// Configure framerate. Kind of weird way of doing it but the only one that works.
device.LockForConfiguration(out error);
// CMTime constructor means: 1 = one second, DETECTION_FPS = how many samples per unit, which is 1 second in this case.
device.ActiveVideoMinFrameDuration = new CMTime(1, DETECTION_FPS);
device.ActiveVideoMaxFrameDuration = new CMTime(1, DETECTION_FPS);
device.UnlockForConfiguration();
}
