title: Auto-Focus: select focus point
body: <p>The camera app that comes with the HTC Desire HD allows the user to touch the screen at the point they wish focus on; a bounding indicator comes up around the area and the auto-focus does its magic. Thus a captured image can have a far point in the top right and a near point in the bottom left, with the user able to select which of these is in focus before taking the picture.</p>
  
  <p>I've been asked to create an app that allows the user to select the region of interest after a picture is taken, obviously it would be good for this region to be in focus before taking the picture as described above.</p>
  
  <p>My app so far does the auto-focus thing on the centre of the image but I can find no reference to selecting the region to focus on in any documentation. Any ideas.</p>