AVI

AVI, which stands for Audio Video Interleave, is a Container format used by Microsoft's Video for Windows multimedia framework. Since it was developed for Windows 3.1 in 1992 it lacks some features found in newer containers like MPEG or MP4, but is still widely used by consumers and even supported by some standalone DVD players. Although still supported in Windows, and suitable for certain formats like DV, it's not a good general purpose container, and even Microsoft uses other containers for their own video formats.

FourCC
In order for Windows to play an AVI file its necessary to know what decoder on your computer should be used to render the video. AVI files all have a property called a FourCC, which consists of four letters, based on what kind of encoding is used. VfW decoders then register particular FourCCs with Windows, letting it know that they can Decode video in those formats. Some FourCCs correspond to a single application, meaning only one Codec can be used for decoding. Others, like DVSC for DV or any of the standard MPEG-4 FourCCs, can be decoded by a variety of VfW decoders that conform to those standards. The FourCC of a file can be changed with a tool called AVI FourCC Changer (see software links below).

MPEG-4
When video enthusiasts began tinkering with MPEG-4 ASP encoding they found that it was possible to store the video in the already deprecated AVI container. Although later on an official MPEG-4 container (MP4) was developed, compatibility with existing tools and VfW codecs has remained popular for MPEG-4 ASP encoding with such codecs as DivX, XviD, and 3ivX.

DVD Player Support
In 2003 the Kiss DP-450 DVD player was introduced to the public. It was the first standalone DVD player capable of MPEG-4 playback. In the years since a number of other manufacturers, including more mainstream companies like Onkyo, Panasonic, and Pioneer, have began selling such DVD players. Although supported features of different MPEG-4 codecs varies somewhat, one common feature is the ability to read AVI files.

DV
Since DV doesn't have an official container of its own most Windows software designed for working with it assumes the AVI container will be used. DV files stored in the AVI container may be of two different types - Type 1 and Type 2.

Type 1 DV
Type 1 DV files are technically not VfW compatible because the video and audio inside must be split into separate streams by DirectShow software, normally implemented in DirectShow. While this affects VfW based tools like VirtualDub, it can be solved by using AviSynth, which is capable of using DirectShow to open files. Type 1 files can also be converted (losslessly) to Type 2 in order to open with standard VfW applications. The format used to mux the video and audio in a Type 1 file is the same as what's used when a camcorder stores it to DV tape.

Type 2 DV
Type 2 DV files can be opened in the same way as other AVI files, meaning you need to have a VfW DV codec installed on your system. While Microsoft provides a DirectShow decoder for Type 1 files, you must use a third party decoder of some kind for Type 2 files.

Uncompressed AVI
AVI files can be created with no Compression, resulting in extremely large file sizes, but with no loss of quality from the input video to the saved file. This also requires no codecs to be installed, either for saving or playback. This is generally not recommended. Instead it's better to use a Lossless Compression format like Huffyuv.

Lossless Compression
If you want to create a smaller AVI than you can get with no compression, but with the highest quality possible, you can also use a lossless codec like HuffYUV or Lagaraith. The files will still be significantly larger than standard compressed files, but good for use as intermediary files for editing and then compressing later.

Return to Introduction to Haali Media Splitter

Related Guides

How to play AVI files

How to play AVI? is probably the most common question a person new to digital video asks. The same question is being asked by many ways: "I downloaded a movie and it wont play", "AVI wont open!" and "This video doesn't work!" -- all of them asking basically the same question. We try to address this question in this article as well as we can.... (Read More)

What codecs to use? The AVIcodec guide

If you have received a video files, such as an AVI file, but cannot play it, it may be because you do not have the appropriate codecs installed on your computer. The video and audio tracks in a file have been "encoded" or "coded", and in order to play the file back you need to "decode" it.... (Read More)

Find what video and audio codecs you need by using GSpot

If you have received a video files, such as an AVI file, but cannot play it, it may be because you do not have the appropriate codecs installed on your computer. The video and audio tracks in a file have been "encoded" or "coded", and in order to play the file back you need to "decode" it.... (Read More)

How to convert video files to DVD using VSO ConvertXtoDVD

ConvertXtoDVD is the new improved software that replaced DivxToDVD from VSO Software. It has the ability to convert multiple file types, including AVI files.... (Read More)

How to convert AVI files (DivX, XviD etc.) to DVD with Avi2DVD

Avi2DVD is a new GUI that uses freeware tools to perform conversions such as AVI to DVD, SVCD, VCD or DVD to DVD, SVCD or VCD.... (Read More)

Extract AC3 from AVI files

This is a very brief guide on how to extract an AC3 surround audio (also known as Dolby Digital) from an AVI movie.... (Read More)

Joining AVI files

If you have multiple AVI files that you would like to join together (like if you made a DVDRip before and ended up with two 700MB AVI files, then you might want to join them together) then this guide will show you how to do just that.... (Read More)

Splitting AVI files

Ok, it happens often that you need to split AVI into smaller files -- maybe you want to fit your DVD rip into 2 CDs or something.... (Read More)

Adding subtitles to AVI

Here is a quick and simple guide to add subtitles to any .avi file that you would like.... (Read More)

Synonyms

Audio Video Interleave

Related glossary terms

Related software tools

	AVI FourCC Changer (Open source) Changes the FourCC code from any AVI file
	AVI ReComp (Freeware) AVI ReComp allows you to recompress your AVI files.
	AVI-Mux GUI (Open source) AVI-Mux GUI is a tool that can create AVI-files with multiple audio streams.
	Avi2Dvd (Freeware) Avi2DVD is a GUI in order to convert with just few clicks an AVI/OGM/MKV/DVD to DVD/SVCD/VCD.
	AVIcodec (Open source) AVIcodec is a nice little tool for identifying what codecs you need in order to play your multimedia files. Program supports MPEG-1/2, AVI, Ogg, ASF, WMV, etc formats.
	avidemux (Open source) Avidemux is a free open-source program designed for multi-purpose video editing and processing.
	avidemux for Mac OS X (Open source) Avidemux is a free open-source program designed for multi-purpose video editing and processing.
	AviSplit classic (Freeware) AviSplit is an application for cutting and rejoining AVI/DivX files.
	AviSynth (Open source) AviSynth is an extremely powerful frameserver for Windows that allows using VirtualDub and TMPGEnc plugins as well as tons of its own plugins to be added to the frameserving process.
	AviTricks classic (Freeware) AviTricks is a non-linear, non-destructive AVI video editor with real-time preview.
	AVI_IO (Freeware) AVI_IO is an excellent and light-weight capture tool that supports most of the regular video capture cards.
	DivX (Ad-supported) The latest version of the DivX. That is, you need to have this file installed if you want to watch DivX movies. And latest codec gives you the best quality.
	DivX (Win98/ME) (Shareware) The latest version of the DivX codec for Win98/ME platforms. You need to have this codec installed in case you want to watch or encode DivX movies.
	DivX ;-) MPEG4 Codec (Freeware) DivX ;-) is a hacked MPEG4 codec that allows you to watch and encode DivX ;-) video clips. You really need this one, trust me...
	DivX Create (Shareware) This is the DivX pack you want if you're planning to encode DivX movies on your own.
	DivX for Linux (Freeware) Official DivX codec for Linux -- provides same features and same quality as the Windows version does.
	DivX for Mac OS X (Shareware) DivX5 for Mac is _the_ official DivX codec for Mac -- it has been developed by DivX Networks, same guys who have developed DivX4 for Win. Excellent MPEG-4 based video codec.
	DivX Pro (Win98/ME) (Shareware) DivX is an extremely popular implementation of the MPEG-4 standard.
	DivX Pro for Mac OS (15 day trial) (Freeware) DivX5 for Mac is _the_ official DivX codec for Mac -- it has been developed by DivX Networks, same guys who have developed DivX4 for Win. Excellent MPEG-4 based video codec.
	DivX Pro for Mac OS X (15 day trial) (Shareware) DivX5 for Mac is _the_ official DivX codec for Mac -- it has been developed by DivX Networks, same guys who have developed DivX4 for Win. Excellent MPEG-4 based video codec.
	Dr. DivX (Freeware) Dr. DivX is officially the unofficial DivX encoding tool to create DivX media files for playback on DivX hardware and software players.
	DVIO (Freeware) DVIO is a very small and free tool for capturing video files from FireWire/IEEE.1394 compatible digital videocameras (most miniDV and D8 cameras).
	DVtool (Freeware) A brilliant toolkit for all your digital video needs.
	FFDSHOW (Open source) FFDSHOW is a super-fast DirectShow decoding filter for decompressing DivX, XviD, WMV, MPEG-1 and MPEG-2 movies and supports subtitles as well. If you ever want to watch movies, get this!
	GSpot (Freeware) GSpot is a nice little tool that allows you to see what codecs your video file uses in order to determine what you need to install on your system to watch it.
	Huffyuv (Freeware) Huffyuv is a lossless video codec that is highly recommended to use in tasks that are done prior encoding to a lossy formats, like DivX or VCD. Must-have codec for video capturing, etc.
	ImTOO AVI MPEG Converter (Shareware) ImTOO AVI MPEG Converter is able to convert avi to mpeg1,mpeg2,mpeg4 and mpeg1,mpeg2 to avi.
	ImTOO AVI to DVD Converter (Shareware) ImTOO AVI to DVD Converter is a DVD burning software which can convert AVI to DVD and burn it on DVD disc.
	Media Player Classic (Open source) Media Player Classic is an extremely light-weight media player for Windows. It looks just like the good-old Media Player v6.4, but has lots of nice extra features.
	MeGUI (Freeware) MeGUI is the most comprehensive GUI based ISO MPEG-4 solution.
	VirtualDub (Freeware) Extremely efficient video capture and processing program. This version is not the latest one, but this is the last version that has ASF support
	VirtualDubMod (Freeware) VirtualDubMod is a modified version of the excellent video handling tool, VirtualDub. VirtualDubMod adds support for MPEG-2, AC3, Ogg Vorbis and VBR MP3 to the original VirtualDub.
	VirtualDubMod Surround (Open source) VirtualDubMod Surround is a VirtualDubMod with some bugs fixed. It's also capable of utilizing 6 channel audio ACM encoders.
	VLC (Open source) VLC (initially VideoLAN Client) is a highly portable multimedia player for various audio and video formats such as MPEG-1, MPEG-2, MPEG-4, DivX, mp3, ogg, ...
	VLC for Linux (Freeware) VLC (initially VideoLAN Client) is a highly portable multimedia player for various audio and video formats such as MPEG-1, MPEG-2, MPEG-4, DivX, mp3, ogg, ...
	VLC for Mac OS X (Intel 32-bit) (Open source) VLC (initially VideoLAN Client) is a highly portable multimedia player for various audio and video formats (MPEG-1, MPEG-2, MPEG-4, DivX, mp3, ogg, ...) as well as DVDs, VCDs, and various st
	VSO ConvertXtoDVD (Shareware) Easy-to-use tool that allows converting any video file format (DivX, AVI, WMV, ..) to a DVD-compliant video.
	WinAVI Video Converter (Shareware) WinAVI Video Converter is software for video conversion.
	WinDV (Freeware) WinDV is a small and easy to use Windows application for capturing videos from DV device (camcorder) into AVI-files.
	XviD Bitrate Calculator (Freeware) Nice little bitrate and resolution calculator for XviD videos, which does everything you can ask from a bitrate calculator. Only nag is the installation of the tool, which can get painful.
	XviD Codec (Open source) XviD is an open source video codec that lets you play and create MPEG-4 compatible videos.
	XviD Codec (Open source) XviD is a MPEG-4 compatible codec, which produces very good video quality -- something that really competes with DivX.