android：相机测光在某些设备中不起作用

Question

我需要计量直播，下面的代码在某些设备（Vivo，oppo）中正常工作，但计量在某些设备（三星和美图）中不起作用，如何计量这些设备？

这是我的代码（触摸屏幕时会调用handleMetering）：

   private void setMeteringParam() {
    synchronized (mCameraLock) {
        Camera.Parameters params = mMasterCamera.getParameters();
        if (params.getMaxNumMeteringAreas() > 0) {
            List<Camera.Area> meteringAreas = new ArrayList<>();
            meteringAreas.add(new Camera.Area(mMeteringRect, 800)); //100%
            params.setMeteringAreas(meteringAreas);
            params.setMeteringAreas(meteringAreas);
            params.setExposureCompensation(0);
            YMFLog.error("wudan", "Enable metering area! Metering Area = " + params.getMeteringAreas().toString());
        } else {
            YMFLog.error("wudan", "metering areas not supported");
        }
        mMasterCamera.setParameters(params);
    }

}

private Rect mMeteringRect = null;
public void handleMetering(MotionEvent event, int width, int height) {
    mMeteringRect = calculateTapArea(event.getX(), event.getY(), 1.0f, width, height);
    if (mMeteringRect != null) {
        setMeteringParam();
    }

}

private Rect calculateTapArea(float x, float y, float coefficient, int w, int h) {
    float focusAreaSize = 20;
    int areaSize = Float.valueOf(focusAreaSize * coefficient).intValue();
    int centerX = (int) (x / w * 2000 - 1000);
    int centerY = (int) (y / h * 2000 - 1000);

    int top = clamp(centerX - areaSize / 2, -1000, 1000 - areaSize);
    int left = clamp(centerY - areaSize / 2, -1000, 1000 - areaSize);

    RectF rectF = new RectF(-(left + areaSize),-(top + areaSize), -left, -top);

    return new Rect(Math.round(rectF.left), Math.round(rectF.top), Math.round(rectF.right), Math.round(rectF.bottom));
}

private int clamp(int x, int min, int max) {
    if (x > max) {
        return max;
    }
    if (x < min) {
        return min;
    }
    return x;
}