There are millions of codecs with varying efficiencies in encoding and compressing multimedia files. However, there are a limited number of popular video codecs and typically, your movie file/CD should be of one of the types in the list below:
MPEG-1 Part 2: One of the most popular, nearly all computers in the world can play this codec. It is regularly used for video CDs (VCDs) and sometime for online video.
MPEG-2 Part 2: Used in most digital video broadcasting, cable distribution and DVD systems. Also used in another form for SVCD. On DVD, it supports widescreen with good picture quality. It’s not as good on SVCD, but definitely better than VCD. (Note: SVCD can hold 40 minutes of video on a CD whereas VCD can fit 60-70 minutes.)
MPEG-4 Part 2: Relative to MPEG-2, it offers better quality and is intended for use on the Internet and broadcast and storage media.
MPEG-4 Part 10: The current state of the art in standardised compression technology. It is rapidly gaining adoption in many applications, and has been recently adopted in a number of companies’ products including the PlayStation Portable, Nero Digital product suite, and Mac OS X v10.4.
DivX, XviD and 3ivx: Video codec packages using MPEG-4 Part 2, with the *.avi, *.mp4, *.ogm or *.mkv file extension formats. Sorenson 3: Many movie trailers on the Internet use this codec. It is used by Apple’s popular QuickTime movies, which have the .mov file extension.
WMV (Windows Media Video): Microsoft’s video codec family includes WMV 7, WMV 8, and WMV 9. It can be used right from low-resolution video for dial-up users to HDTV. Files can be written to CD-Rs and DVD-Rs or output to many types of devices. Also useful for Media Center PCs, WMV can be considered a version of the MPEG-4 codec design.
RealVideo: Developed by RealNetworks, a popular codec (.ram file extension) technology a few years ago, now fading in importance for a variety of reasons.
Flash Video: Gaining popularity of late, the Macromedia Flash Video file format (FLV) is becoming a standard on many Web sites. To play back files, a Macromedia Flash Video player is embedded into the Web page. You may need to also get the Flash plug-in for your browser.
Finding out what codec is missing can be a frustrating process if done manually. Thankfully, there are codec information software tools that will do the job for you. Select the multimedia file that is not playing from within the codec information tool, and it will inform you what codec is required to play the file correctly. Some of the tools also give you direct links to download the missing codecs! Take your pick from some of the popular commercial and freeware tools listed below.
VideoInspector (www.kcsoftwares.com/index.php?vtb): This gives direct download links to missing codecs after analysing the file format. Can analyse most file formats such as AVI, MPEG, etc.
Gspot (www.headbands.com/gspot/): Even though it has some features missing that you can find in others, Gspot is a useful tool. It was a pioneer in troubleshooting video applications.
MediaInfo (http://mediainfo.sourceforge.net/en): An open source alternative to GSpot.
AVICodec (http://avicodec.duby.info): Another useful codec information tool.