public void close() {
        Util.validateMainThread();

        if (open) {
            cameraThread.enqueue(closer);
        } else {
            cameraClosed = true;
        }

        open = false;
    }
Changes the settings for Camera.

@param callback {@link CameraParametersCallback}
zxing-android-embedded/src/com/journeyapps/barcodescanner/camera/CameraInstance.java