title: Draw a rectangleBox on CameraX preview and capture only that area
body: <p>I want to open the camera with a rectangle border over it. And capture only the rectangle area image. The rectangle border can resize as per the user's choice.
  Tried with many SO link but still no answer.
  Below is the SO link that I want to achieve.
  <a href="https://stackoverflow.com/questions/55006224/display-a-rectangular-bounding-box-overlay-on-custom-camera2-api-so-only-the-i">Display a rectangular bounding box (overlay) on custom Camera2 API so only the image inside the box is captured</a></p>