How to determine a missing Codec for a video file

[videobruce]

Trying to play certain video files in different viewers (IrFanView for starters) and some won't open because a certain Codec is missing. Others with that same extension will play.
How do you determine what Codec is needed with a given file before you try to open it other than looking at the file extension?

 

[Tarkus]

I've had luck by dropping the video file into notepad and looking in the first few lines, the name of the codec should be visible there.

 

[Rick]

You could just hit it with a hammer and install the nimo codec pack - There's not a useful codec that exists that isn't included.

 

[SNGX1275]

I've heard good things about gspot.
But I think it only works with .avi files, but then again those are the ones that seem to require the more obscure codecs.

 

[Nodsu]

Nimo is evil IMHO..
There is a program called avicodec that will tell you the vid and sound codec used in .avi and some .mpg files