title: How to extract List - movi tag from AVI files on iOS
body: <p>I am trying to retrieve RIFF data from AVI file in my iOS app.  I tried to convert AVI file to NSDATA and then i have converted to NSASCIIStringEncoding and i am getting all tag as string but how to retrieve particular tag,in this case I am getting all data but as there is lots data inside it, it is tough to get data from specific tags. I want to retrieve specific data from the specific tag.  Here I have enclosed screenshot which shows how data looks like on Windows computer. I have used software named AVI master to see RIFF data in windows computer .As you can see in the screenshot, I will need data associated with 03tx tag. 
  I tried all possible ways to read chunk by chunk and also tried Libavformat library, but no success. Is there any other way to get RIFF data associated with AVI file? 
  Please advise. </p>
  
  <p><a href="https://i.stack.imgur.com/fbrmv.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/fbrmv.png" alt=""></a></p>