void BindScan(ProcessCameraProvider cameraProvider, int width, int height)
{
var preview = new Preview.Builder().Build();
// 绑定预览
preview.SetSurfaceProvider(binding !.previewView.SurfaceProvider);
// 使用后置相机
var cameraSelector = new CameraSelector.Builder()
.RequireLensFacing(CameraSelector.LensFacingBack)
.Build();
// 绑定图片扫描解析
var imageAnalysis = new ImageAnalysis.Builder()
.SetTargetResolution(new(width, height))
.SetBackpressureStrategy(ImageAnalysis.StrategyKeepOnlyLatest)
.Build();
// 绑定图片扫描解析
analyser = new((barCodes, imageWidth, imageHeight) =>
{
// 解绑当前所有相机操作
cameraProvider.UnbindAll();
ScanCompletedHandler?.Invoke(barCodes.Select(x => x.GetRawBytes()));
ScanCompletedHandler = null;
Finish();
});
imageAnalysis.SetAnalyzer(Executors.NewSingleThreadExecutor(), analyser);
camera = cameraProvider.BindToLifecycle(this, cameraSelector, imageAnalysis, preview);
}
private void FindAndOpenCamera()
{
bool cameraPermissions = CheckCameraPermissions();
if (!cameraPermissions)
{
return;
}
string errorMessage = "Unknown error";
bool foundCamera = false;
IListenableFuture cameraProviderFuture = ProcessCameraProvider.GetInstance(this);
cameraProviderFuture.AddListener(new Runnable(() =>
{
// Camera provider is now guaranteed to be available
mCameraProvider = cameraProviderFuture.Get() as ProcessCameraProvider;
try
{
// Find first back-facing camera that has necessary capability.
CameraSelector cameraSelector = new CameraSelector.Builder().RequireLensFacing((int)mLensFacing).Build();
// Find a good size for output - largest 4:3 aspect ratio that's less than 720p
Preview.Builder previewBuilder = new Preview.Builder()
.SetTargetAspectRatio(AspectRatio.Ratio43);
Camera2Interop.Extender previewExtender = new Camera2Interop.Extender(previewBuilder);
previewExtender.SetSessionCaptureCallback(mCaptureCallback);
Preview preview = previewBuilder.Build();
// Must unbind the use-cases before rebinding them
mCameraProvider.UnbindAll();
ICamera camera = mCameraProvider.BindToLifecycle(
this as ILifecycleOwner, cameraSelector, preview);
if (camera != null)
{
// Found suitable camera - get info, open, and set up outputs
mCameraInfo = camera.CameraInfo;
mCameraControl = camera.CameraControl;
preview.SetSurfaceProvider(this);
foundCamera = true;
}
if (!foundCamera)
{
errorMessage = GetString(Resource.String.camera_no_good);
}
SwitchRenderMode(0);
}
catch (CameraAccessException e)
{
errorMessage = GetErrorString(e);
}
if (!foundCamera)
{
ShowErrorDialog(errorMessage);
}
}), ContextCompat.GetMainExecutor(this));
}
/// <summary>
/// https://codelabs.developers.google.com/codelabs/camerax-getting-started#3
/// </summary>
private void StartCamera()
{
var cameraProviderFuture = ProcessCameraProvider.GetInstance(this);
cameraProviderFuture.AddListener(new Runnable(() =>
{
// Used to bind the lifecycle of cameras to the lifecycle owner
var cameraProvider = (ProcessCameraProvider)cameraProviderFuture.Get();
// Preview
var preview = new Preview.Builder().Build();
preview.SetSurfaceProvider(viewFinder.CreateSurfaceProvider());
// Take Photo
this.imageCapture = new ImageCapture.Builder().Build();
// Frame by frame analyze
var imageAnalyzer = new ImageAnalysis.Builder().Build();
imageAnalyzer.SetAnalyzer(cameraExecutor, new LuminosityAnalyzer(luma =>
Log.Debug(TAG, $"Average luminosity: {luma}")
));
// Select back camera as a default, or front camera otherwise
CameraSelector cameraSelector = null;
if (cameraProvider.HasCamera(CameraSelector.DefaultBackCamera) == true)
{
cameraSelector = CameraSelector.DefaultBackCamera;
}
else if (cameraProvider.HasCamera(CameraSelector.DefaultFrontCamera) == true)
{
cameraSelector = CameraSelector.DefaultFrontCamera;
}
else
{
throw new System.Exception("Camera not found");
}
try
{
// Unbind use cases before rebinding
cameraProvider.UnbindAll();
// Bind use cases to camera
cameraProvider.BindToLifecycle(this, cameraSelector, preview, imageCapture, imageAnalyzer);
}
catch (Exception exc)
{
Log.Debug(TAG, "Use case binding failed", exc);
Toast.MakeText(this, $"Use case binding failed: {exc.Message}", ToastLength.Short).Show();
}
}), ContextCompat.GetMainExecutor(this)); //GetMainExecutor: returns an Executor that runs on the main thread.
}
/// <summary>
/// 初始化并绑定摄像头
/// </summary>
/// <param name="lifecycleOwner"></param>
public void InitAndStartCamera(ILifecycleOwner lifecycleOwner, Action <bool, string> InitCallBack)
{
var cameraProviderFuture = ProcessCameraProvider.GetInstance(this.Context);
cameraExecutor = Executors.NewSingleThreadExecutor();
cameraProviderFuture.AddListener(new Java.Lang.Runnable(() =>
{
// Used to bind the lifecycle of cameras to the lifecycle owner
var cameraProvider = (ProcessCameraProvider)cameraProviderFuture.Get();
// Preview
var preview = new Preview.Builder()
.Build();
preview.SetSurfaceProvider(_CameraPreView.SurfaceProvider);
// Take Photo
this._ImageCapture = new ImageCapture.Builder()
.SetTargetResolution(new Size(CaptureImageSize_Width, CaptureImageSize_Height))
.Build();
// Frame by frame analyze(Not Use Now)
var imageAnalyzer = new ImageAnalysis.Builder().Build();
imageAnalysisFrameProcess = new ImageAnalysisFrameProcess();
imageAnalyzer.SetAnalyzer(cameraExecutor, imageAnalysisFrameProcess);
//imageAnalyzer.SetAnalyzer(cameraExecutor, new LuminosityAnalyzer(luma =>
// Log.Debug("", $"Average luminosity: {luma}")
// ));
#region Select back camera as a default, or front camera otherwise
CameraSelector cameraSelector = null;
//if (cameraProvider.HasCamera(CameraSelector.DefaultBackCamera) == true)
// cameraSelector = CameraSelector.DefaultBackCamera;
//else if (cameraProvider.HasCamera(CameraSelector.DefaultFrontCamera) == true)
// cameraSelector = CameraSelector.DefaultFrontCamera;
//else
// throw new System.Exception("Camera not found");
switch (CameraFacing)
{
case CameraFacing.Back:
if (cameraProvider.HasCamera(CameraSelector.DefaultBackCamera) == true)
{
cameraSelector = CameraSelector.DefaultBackCamera;
}
else
{
if (cameraProvider.HasCamera(CameraSelector.DefaultFrontCamera) == true)
{
cameraSelector = CameraSelector.DefaultFrontCamera;
}
else
{
InitCallBack?.Invoke(false, "Not found any camera device");
return;
}
}
break;
case CameraFacing.Front:
{
if (cameraProvider.HasCamera(CameraSelector.DefaultFrontCamera) == true)
{
cameraSelector = CameraSelector.DefaultFrontCamera;
}
else
{
if (cameraProvider.HasCamera(CameraSelector.DefaultBackCamera) == true)
{
cameraSelector = CameraSelector.DefaultBackCamera;
}
else
{
InitCallBack?.Invoke(false, "Not found any camera device");
return;
}
}
}
break;
}
#endregion
try
{
// Unbind use cases before rebinding
cameraProvider.UnbindAll();
// Bind use cases to camera
var camera = cameraProvider.BindToLifecycle(lifecycleOwner, cameraSelector, preview, _ImageCapture, imageAnalyzer);
_CameraController = camera.CameraControl;
_CameraInfo = camera.CameraInfo;
InitCallBack?.Invoke(true, "");
}
catch (Exception exc)
{
Toast.MakeText(this.Context, $"Use case binding failed: {exc.Message}", ToastLength.Short).Show();
}
}), AndroidX.Core.Content.ContextCompat.GetMainExecutor(this.Context));
}
