[opus] opus file trimming/clipping

[Timothy B. Terriberry]

Matt Ruck wrote:
> I think producing a new .opus file would be ideal to maintain the
> benefits of using the opus codec for transmission over the Internet, and
> I have had success encoding to and decoding from .opus to .wav using
> opus-tools.

Okay, opusfile produces decoded data, so that's probably not what you 
want to be looking at. You want a tool similar to vcut from 
vorbis-tools. No one's written an equivalent for Opus. It's not _too_ 
much work to do so, but it does require a fairly good understanding of 
Ogg and the Ogg mapping for Opus (see https://www.xiph.org/ogg/doc/ and 
http://tools.ietf.org/html/draft-ietf-codec-oggopus).