title: Need example of how to create/manipulate image pixel data with iPhone SDK
body: <p>Looking for a simple example or link to a tutorial.</p>
  
  <p>Say I have a bunch of values stored in an array.  I would like to create an image and update the image data from my array.  Assume the array values are intensity data and will be updating a grayscale image.  Assume the array values are between 0 and 255 -- or that I will convert it to that range.</p>
  
  <p>This is not for purposes of animation.  Rather the image would be updated based on user interaction.  This is something I know how to do well in Java, but am very new to iPhone programming.  I've googled some information about CGImage and UIImage -- but am confused as to where to start.</p>
  
  <p>Any help would be appreciated.</p>