| static private LogWarn ( string format ) : void | ||
| format | string | |
| return | void | |
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();
}
}
