How to get Color Temperature from Color Correction Gain

I am trying to find out the Color Temperature of a Photo captured by the Camera.

final CameraCaptureSession.CaptureCallback previewSSession = new CameraCaptureSession.CaptureCallback() {
    @Override
    public void onCaptureStarted(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, long timestamp, long frameNumber) {
        super.onCaptureStarted(session, request, timestamp, frameNumber);
    }

    @Override
    public void onCaptureCompleted(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, TotalCaptureResult result) {
        super.onCaptureCompleted(session, request, result);
        RggbChannelVector rggbChannelVector = result.get(CaptureResult.COLOR_CORRECTION_GAINS);
        getColorTemperature(rggbChannelVector);

        startCamera();
    }
};

private void getColorTemperature(RggbChannelVector rggbChannelVector) {
    //rggbChannelVector.getRed() = 2.192929
    //rggbChannelVector.getGreenEven() = 1.0
    //rggbChannelVector.getGreenOdd() = 1.0
    //rggbChannelVector.getBlue() = 1.832323
}

iOS seems to have a readily available method to do that temperatureAndTintValues

While searching for something similar(in Java or any other language which I can adopt), almost all such methods expect a RGB value with [0, 255] range.

There are few methods to convert XYZ to CCT(Correlated Color Temperature) but even to get the XYZ value correct I need RGB values with in [0, 255]

As you can see the values from COLOR_CORRECTION_GAINS are >1 i.e greater than 255 which is not unusual because its a gain and iOS returns similar values(greater than 1).