Merge pull request w3c#3 from guest271314/master

Merging media fragments from different input containers to a single output container

Author: pthatcherg

explainer.md

@@ -50,6 +50,7 @@ Provide web apps with efficient access to built-in (software and hardware) media
  - control over buffer behavior
  - spatial and temporal scalability
 - Decoded and encoding images
+- Reencoding multiple input media streams in order to merge many encoded media streams into one encoded media stream.
 
 
 ## Proposed solutions