title: Video recorded on iOS plays upside down
body: <p>During my work I usually use <code>CVOpenGLESTextureCacheCreateTextureFromImage</code> to get the cache texture from fob. I then use asssetwriter to write a mov file, the mov plays good but the video is upside-down.</p>
  
  <p>I did search the internet and found that i should code this :</p>
  
  <pre><code>assetWriterInput.transform=CGAffineTransformMakeScale(1.0, -1.0);
  </code></pre>
  
  <p>It works fine, but when I play it on Windows XP, it is still upside down. I found that it plays well just on iOS or the  Quicktime video player on non Apple OS.</p>
  
  <p>So what's the reason? Why does it not work?</p>