How to rotate android device camera preview(libgdx)

Question

I'm using libgdx to make an application and I need to use the camera so I followed this tutorial and all my camera feed is rotated 90 degrees but they are being drawn as if they weren't. Unfortunately that means the preview is totally distorted and is very hard to use.

I won't post my code here unless snippets are asked for because I copy-pasted the code from the tutorial into my game.. The only change I recall making was as follows.

I changed the original surfaceCreated() method in CameraSurace.java

 public void surfaceCreated( SurfaceHolder holder ) {
    // Once the surface is created, simply open a handle to the camera hardware.
    camera = Camera.open();
}

to open the front facing camera (Im using a Nexus 7 that only has a front camera...)

    public void surfaceCreated( SurfaceHolder holder ) {
    // Once the surface is created, simply open a handle to the camera hardware.
    camera = openFrontFacingCamera();
}


@SuppressLint("NewApi")
private Camera openFrontFacingCamera() 
{
    int cameraCount = 0;
    Camera cam = null;
    Camera.CameraInfo cameraInfo = new Camera.CameraInfo();
    cameraCount = Camera.getNumberOfCameras();
    for ( int camIdx = 0; camIdx < cameraCount; camIdx++ ) {
        Camera.getCameraInfo( camIdx, cameraInfo );
        if ( cameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_FRONT  ) {
            try {
                cam = Camera.open( camIdx );
            } catch (RuntimeException e) {
                System.out.println("Falied to open.");
            }
        }
    }

    return cam;
}

Other than that change the rest of the code is almost the exact same (excluding minor variable changes and such.)

Answer 1

You can use the ExifInterface class to determine the ORIENTATION_TAG associated with your image and rotate the image accordingly.

The code would look like this:

ei = new ExifInterface(imagePath); orientation = ei.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL); switch (orientation) { case ExifInterface.ORIENTATION_ROTATE_90: imageView.setRotation(90); break; ... default: break; }

Answer 2

Upon diving into the camera API, I found that all I have to do is use a nice little method called setDisplayOrientation(90) and it works perfectly now.

revised code:

    @SuppressLint("NewApi")
public void surfaceCreated( SurfaceHolder holder ) {
    // Once the surface is created, simply open a handle to the camera hardware.
    camera = openFrontFacingCamera();
    camera.setDisplayOrientation(90);
}


@SuppressLint("NewApi")
private Camera openFrontFacingCamera() 
{
    int cameraCount = 0;
    Camera cam = null;
    Camera.CameraInfo cameraInfo = new Camera.CameraInfo();
    cameraCount = Camera.getNumberOfCameras();
    for ( int camIdx = 0; camIdx < cameraCount; camIdx++ ) {
        Camera.getCameraInfo( camIdx, cameraInfo );
        if ( cameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_FRONT  ) {
            try {
                cam = Camera.open( camIdx );
            } catch (RuntimeException e) {
                System.out.println("Falied to open.");
            }
        }
    }

    return cam;
}

PS only reason I'm ignoring the NewApi is because I know the exact device this app will be running on, and it is specific to that device... Would not recommend unless you know that the device's API is high enough... (it only requires API 8)