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File Formats and Codecs You Need to Know When Working with Video

Many of us have run into the complication of receiving a file format or DVD that our computer can t play. Usually you ll get an error message  codec not supported  or  can t find file codec  and not knowing what a  codec  is you give up and think something is broken. Unfortunately, that s not the case at all, instead your computer is missing a simple, but key element needed to play your video.

Watching DVDs and video on your computer is easy if you just have the right players and a little knowledge about codecs. There are many different kinds of video file formats and codecs. Here, we are going to explain some of the most common formats and where you can download small plug-in codecs and players for free.

DVD Video/MPEG-2
DVDs are made up of many file types, but the portion that contains the video is usually an MPEG-2 or VOB file. Out often you ll place a DVD in your DVD drive expecting to watch a movie and nothing happens, or if you re using Windows Media Player and computer with Windows XP you receive an error message, usually something about codecs, and unable to read the disc. This is because you are missing a DVD decoder or sometimes called an MPEG-2 decoder. This is a little piece of information that your media player is missing keeping it from recognizing the disc in your drive. It s like the key fits in the slot, but won t actually open the door.

The only way to fix this problem is to download a DVD/ MPEG-2 encoder DVD player software.

However, this may not be the case if you have Windows Vista. Windows Vista Home Premium and Ultimate include Windows Media Center which already includes DVD playback.

For those using XP check out our reviews of DVD player software.

Or you can download VideoLan VLC a popular and free media player that supports all of the codecs mentioned in this article including MPEG-2.

Video_TS/ Audio_TS
Video_TS and Audio_TS files are the files you see when you rip the information from a DVD to your hard drive. The Video_TS contains all the information your DVD needs for playback, whereas, the Audio_TS file is usually empty but should to be included for audio and voice synch compatibility with some older stand alone DVD players.

Video_TS files are usually made up of several file types including the VOB files mentioned earlier, IFO and BUP. If you already have DVD player software installed it s likely that your software will automatically assign your VOB files, and sometimes IFO files, as MPEG-2 and you ll never know the difference.

However, if you rip your DVD using popular programs like DVD Shrink or DVD Decryptor, your Video_TS files will have several video files each containing some kind of video information; the majority of video information is stored in the VOB files and can be played on DVD player software and the aforementioned VLC media player.

IFO files work with the VOB files and tell the DVD player which screen to start on, where chapters are split and where the audio is located. Most DVD rippers and video converters rely on VOB files, but some argue that IFO files are more valuable and create a better quality copy.

BUP files are less common than VOB and IFO files. They contain the same information as IFO files and are intended as backups.

AVI is a very popular video container created by Microsoft. An AVI file is actually compatible with several video codecs including DivX, Xvid, MOV and more. To play an AVI file you have to have the appropriate codecs installed.

Additionally, most DV camcorder use a compressed AVI file called DV-AVI. Eventually, you would convert his file to something more compatible with your software usually a more standard AVI for computer playback or MPEG codec for DVD encoding and playback.

Windows Media Player and Quicktime media player will support AVI files if you have the correct codecs installed. Most common AVI codecs are free to install. See below for common AVI codecs.

DivX is increasingly becoming a more common video codec, usually in an AVI container. Usually you ll have a file with a .avi extension but it will contain a video encoded as DivX. You can download the Divx codec for free and play your videos in Windows Media Player, Apple QuickTime and several DVD Player software programs.

Some DVD players can also read DivX. Compatibility is usually displayed directly on the DVD player.

Xvid files function very similarly to DivX files. Like DivX, Xvid is a video codec usually in an AVI container. This means your video file may say .avi, but it is actually encoded using Xvid. All you need to do is download the free Xvid codec. Xvid is arguably better than DivX in that it allows for faster data transmission and more efficient storage. However, Xvid isn t as common or popular as DivX and is compatible with fewer media players.

WMV stands for Windows Media Video. It is a proprietary video format developed by Microsoft. Windows Media Player natively plays WMV files and if you are using a computer with a Windows based operating system the only download you should need is the Windows Media Player. If you are using a Mac you can download a third-party plug-in for QuickTime.

Windows Vista already includes Windows Media Player as part of the operating system and shouldn t require any additional downloads to play WMV files.

MOV is a video container file, much like AVI, developed by Apple for their QuickTime media player. Sometimes MOV movies will have a .qt file extension. Either way these are video formats designed specifically for the QuickTime media player.

QuickTime is a free media player that can be installed on Mac and Windows computers.

MP4 is a format that is commonly used for video files on iPod and PSP and is based on QuickTime s MOV container. Therefore, the MP4 format is usually associated with Apple software. However, the popularity of iPod has forced many manufactures to make their desktop media players more compatible with MP4 files.

Software like QuickTime, iTunes, RealPlayer and Zune Marketplace support MP4 files without any additional codec downloads. Windows Media Player on the other hand cannot easily play MP4 or MOV files.

When dealing with multiple file formats from various sources, it s best to have multiple media player choices. Although it would be nice to have one media player for all your video needs there is just too much competition and contention among manufacturers.

Some media players like VLC and Media Player Classic try to accommodate most users and are actually pretty successful but they are usually secondary players to Windows Media Player and QuickTime that come preinstalled with your operating system.

Also, you may be interested in checking out our DVD Authoring Software Review!