A CDE Definition
Video for Windows
Microsoft's first video playback implementation in Windows. Featuring the AVI movie format, Video for Windows (VfW) had to be installed separately in Windows 3.x, but, starting with Windows 95, it was incorporated into the OS. Initially, the Video 1, RLE and Indeo codecs (compression methods) were included. Windows 95 added the Cinepak codec and provided drivers for Sony ViSCA VCRs and LaserDiscs. Playback quality was rather poor on 486s and earlier Pentiums; however, in the late 1990s, the DivX codec was introduced into the AVI format and greatly improved the video playback. See DivX.
(1) A family of video codecs, formats and software from DivXNetworks, Inc., San Diego, CA (www.divx.com) that is popular for downloading movies from the Internet. Based on MPEG-4, DivX can compress a DVD movie to fit on a CD, and DivX HD can reduce an HD movie to fit on a DVD. The DivX software provides tools for encoding in DivX and MPEG-4, as well as a player for DivX, MPEG-4 and other video formats.
In the late 1990s, DivX was the first video codec for the Windows AVI container format that provided strong compression along with good picture quality. Enabling acceptable video to be streamed over the Internet, DivX quickly became the predominant video compression method for the AVI format (see AVI).
DivX Formats: AVI and MKV Containers
From its development as a codec, DivX evolved into a specification for the AVI container that uses the DivX or Xvid codecs and MP3 or AC-3 audio. Developers creating DivX Media Format (DMF) AVI files, which use an .AVI or .DIVX file extension, adhere to the DivX encoding guidelines. The DivX format also became popular on Divx-certified consumer electronics devices, including DVD and Blu-ray players, portable video players and mobile phones.
The newer DivX Plus HD format uses the MKV/Matroska container with H.264 video and AAC audio (see Matroska). DivX Plus HD supports multilingual subtitles, surround sound and multiple audio tracks and titles. Like the DivX format, encoders must comply with certain specifications.
The following table of file sizes comes from an actual video that was available on the Web in multiple formats. Note that the iPod and PSP formats support only tiny screens. See XviD.
PlayStation Portable (PSP) 42
QuickTime (MOV) 135
Windows Media (WMV) 191
(2) (Divx) (DIgital Video EXpress) A DVD rental system rolled out in 1998 and taken off the market one year later due to poor sales. A joint venture of Circuit City and a Los Angeles entertainment law firm, Divx was a special type of DVD disc playable only in a Divx-enabled DVD player. Consumers paid a rental charge for the non-returnable disc, which was good for two days after its first viewing. Additional time as well as unlimited use could be purchased via modem from the Divx player. A major problem was that Divx discs registered to a specific machine could not be played on other Divx players.
(3) A copy of the DVD copy protection decryption algorithm that was lifted from a media player and passed around hacker sites. The Divx name was used in honor of the defunct Digital Video Express system.
Before/After Your Search Term
Terms By Topic
Click any of the following categories for a list of fundamental terms.