title: Camera cannot detect face with medium resolution in flutter
body: <p>I'm making an app can detect face in flutter with firebase-ml-vision package but the it can detect with every resolution but medium. It's a best solution for my app since with medium resolution, the quality of image is not too low but still keep the performance smooth.</p>
  
  <p>Is that a bug? This is my code:</p>
  
  <pre><code>Center(
      child: Container(
        child: RotatedBox(
          quarterTurns:
          (MediaQuery
              .of(context)
              .orientation == Orientation.landscape)
              ? 3
              : 0,
          child: CustomPaint(
            foregroundPainter:
            (faces.isEmpty) ? null : MyPainter(faces, imageSize),
            child: AspectRatio(
              aspectRatio: controller.value.aspectRatio,
              child: CameraPreview(controller),
            ),
          ),
        ),
      ),
    ),
  </code></pre>
  
  <p>I have an idea that I can use an camera controller with low resolution to detect and other camera with high resolution to display. Is it okay to have 2 camera controller in a same page?</p>