How do I find which codec is needed to play an AVI file?

he AVI file is a basically a wrapper that can contain a multitude of different formats of video and audio. If you don’t have the correct codec installed on your PC, you will not be able to play any AVI that makes use of that format but it is often not simple to figure out what codec you need. To help get round this problem, Richard Thomas has written a helpful application that you can use to determine which codec a given AVI file needs. You can download the program from:

Run it from a DOS prompt using the syntax “qaviinfo <avi_filename>” and it will provide information about the contents of the AVI. The output will look something like:

File Info:

# of streams : 2

Size : 300x224

File Type : AVI Default File Handler

Stream Info:

Type Codec Rate Scale Length

vids IV32    12     1     58

auds      11289   512    106

To determine the video codec, look for the line starting “vids” in the “Stream Info:” section. The FOURCC of the codec is given immediately to the right of “vids”. Knowing this, you can cross reference the FOURCC on the Compressed Formats/Codecs page of this site. If you are lucky, you may even find a link to download the software you need to play the AVI.

If you don’t want to download and run Richard’s app, you can also try this simple method to determine the FOURCC. If you open the AVI file in Windows Wordpad (in Start/Programs/Accessories) you should see something along the lines of “vidsXXXX” somewhere in the top few lines of garbage displayed. In this case, the XXXX is the FOURCC that the AVI file needs to decode its video.

Another option is to try Andre John Mas‘ Java RiffFileReader app. Obviously, you will need to have Java installed to use this.