Confused between Encoder and Video type

[linuxking]

I'm confused about the distinction between encoders and videotypes. By video types, I AVI, MPEG, DIVX - vs. Intel 5.04, Cineplex, Windows MPEG-2 Type 1, and so on.

I thought, for example, AVI has a particular spec for how video and sound is encoded. You could change things within AVI - like resolution. But when I started fooling with ULead, Virtual Dub, and VCD Easy; I had to start fooling with the codec.

For example, in ULead when I capture a file from my camcorder with a firewire connection, I save as AVI *BUT* I also chose the codec. I could use any codec on my computer that ULead 'found' - like the Intel 5.04 or Windows MPEG-2 Type 1. This affected the quality of the capture - and file size.

So, where and what is AVI and why can I use an MPEG-2 codec to capture AVI? I thought if I wanted to capture and compress with MPEG-2, I saved as MPEG.

Thanks for reading this and your replies are appreciated.

[larsli]

Found this in a newsgroup:
AVI stands for Audio Video Interleaved. The .AVI format defines where the
computer should expect to find header information, audio data, and video
data. The data itself may be compressed/encoded in a manner unrelated to the specification of the .AVI file format.