title: Android pinch zoom large image, memory efficient without losing detail
body: <p>My app has to display a number of high resolution images (about 1900*2200 px), support pinch zoom. To avoid Out of memory error I plan to decode image to show full screen by using</p>
  
  <pre><code>options.inSampleSize = scale (scale was calculated as Power of 2 as Document)
  </code></pre>
  
  <p>(My view i used is <code>TouchImageView</code> extends of <code>ImageView</code>)</p>
  
  <p>So i can quickly load image and swipe smoothly between screens(images). However, when i pinch zoom, my app loses detail because of scaled image.
  If i load full image, i can't load quickly or smoothly swipe, drag after pinch zoom.
  Then i try to only load full image when user begin pinch-zooming, but i still can't drag smoothly image because of very large image. Android gallery can do it perfectly even 8Mpx images.</p>
  
  <p>Anyone can help me. Thanks in advance</p>