- Advanced Member
- Posts: 168
- Joined: Thu Feb 10, 2011 12:23 am
- Location: EU
A video file (.avi, .mp4) compressed using the X codec will be different from a file (also .avi, .mp4) compressed using the Y codec, although they both have the same extension, as you mentioned.
I recommend you to check out Codecs FAQ page, i've added links to some good resources there.