Where can i find collection of various common File Extension structure?

Suppose i want to fstream some image file like jpeg, i'd need to know its internal structure, and how it is stored. Therefore, i just want to know if there exist some website that collect information on structure of each file extension? There's only website开发者_如何学C such as filext.com that tell us about what kind of file it is. I just want to know if there exists websites or documents that generally tell me all common file extension's structure.

PS: if there isn't one, then i'll have to lookup each file extensions' documentation...

http://www.wotsit.org/ Has descriptions for many file formats.

You will have a hard time implementing parsers for "all common file extensions" though. You are probably going to have better success using libraries, or depending what you are trying to do, using OS-specific file info functions. Maybe even supporting an existing plugin format like Windows Explorer.