private int FindBackFacingCamera()
{
var cameraId = 0;
// Search for the front facing camera
int numberOfCameras = Camera.NumberOfCameras;
for (int i = 0; i < numberOfCameras; i++)
{
var info = new Camera.CameraInfo();
Camera.GetCameraInfo(i, info);
if (info.Facing == Camera.CameraInfo.CameraFacingBack)
{
cameraId = i;
break;
}
}
return(cameraId);
}
private void prepareCamera(int encWidth, int encHeight)
{
if (_camera != null)
{
throw new RuntimeException("camera already initialized");
}
Camera.CameraInfo info = new Camera.CameraInfo();
// Try to find a front-facing camera (e.g. for videoconferencing).
int numCameras = Camera.NumberOfCameras;
for (int i = 0; i < numCameras; i++)
{
Camera.GetCameraInfo(i, info);
if (info.Facing == Camera.CameraInfo.CameraFacingFront)
{
_camera = Camera.Open(i);
break;
}
}
if (_camera == null)
{
Log.Debug(TAG, "No front-facing camera found; opening default");
_camera = Camera.Open(); // opens first back-facing camera
}
if (_camera == null)
{
throw new RuntimeException("Unable to open camera");
}
Camera.Parameters parms = _camera.GetParameters();
choosePreviewSize(parms, encWidth, encHeight);
// leave the frame rate set to default
_camera.SetParameters(parms);
Camera.Size size = parms.PreviewSize;
Log.Debug(TAG, "Camera preview size is " + size.Width + "x" + size.Height);
}
public override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
// Create a RelativeLayout container that will hold a SurfaceView,
// and set it as the content of our activity.
mPreview = new Preview(this.Activity);
// Find the total number of cameras available
mNumberOfCameras = Camera.NumberOfCameras;
// Find the ID of the default camera
Camera.CameraInfo cameraInfo = new Camera.CameraInfo();
for (int i = 0; i < mNumberOfCameras; i++)
{
Camera.GetCameraInfo(i, cameraInfo);
if (cameraInfo.Facing == Camera.CameraInfo.CameraFacingBack)
{
mDefaultCameraId = i;
}
}
SetHasOptionsMenu(mNumberOfCameras > 1);
}
/**
* Gets the current screen rotation in order to understand how much
* the surface needs to be rotated
*/
private void UpdateCameraDisplayOrientation()
{
int cameraID = _cameraId;
if (_camera == null)
{
Console.WriteLine("updateCameraDisplayOrientation(): warning, camera is null");
return;
}
int result = 0;
MainActivity parentActivity = (MainActivity)Context;
int rotation = (int)parentActivity.Window.WindowManager.DefaultDisplay.Rotation;
int degrees = 0;
switch (rotation)
{
case (int)SurfaceOrientation.Rotation0:
degrees = 0;
break;
case (int)SurfaceOrientation.Rotation90:
degrees = 90;
break;
case (int)SurfaceOrientation.Rotation180:
degrees = 180;
break;
case (int)SurfaceOrientation.Rotation270:
degrees = 270;
break;
}
if ((int)Build.VERSION.SdkInt >= 9)
{
// on >= API 9 we can proceed with the CameraInfo method
// and also we have to keep in mind that the camera could be the front one
Camera.CameraInfo info = new Camera.CameraInfo();
Camera.GetCameraInfo(cameraID, info);
if (info.Facing == Camera.CameraInfo.CameraFacingFront)
{
result = (info.Orientation + degrees) % 360;
result = (360 - result) % 360; // compensate the mirror
}
else
{
// back-facing
result = (info.Orientation - degrees + 360) % 360;
}
}
else
{
// TODO: on the majority of API 8 devices, this trick works good
// and doesn't produce an upside-down preview.
// ... but there is a small amount of devices that don't like it!
result = Math.Abs(degrees - 90);
}
_camera.SetDisplayOrientation(result); // save settings
}
