No, but that sounds like an excellent open source project to start on.
The problem comes in that wireshark is able to do it because protocols don't change much (they can't; applications wouldn't be able to keep up and interoperability wouldn't happen). This isn't true of file formats, however, which have the annoying tendency to change more frequently.
You should check out the 'file' command (if you haven't yet) which identifies files quite well. Then you could pull in some programs like identify from the ImageMagick suite which could help you break down files.
But then you'll quickly realize that every single library must be pulled in because files are huge and complex and not simple to break down in the first place (unlike packets). That's the whole reason that applications are so large in the first place! To manipulate those nasty files!
I know all about file, but what I'm looking for is something that actually lets me explore the data in the file, rather than just telling me what kind of file it is. – dirtside – 2011-03-23T06:04:02.373