What is DVD?
DVD (Digital Versatile Disc or Digital Video Disc) is a format not unlike CD, only it holds more data and stores it in a format that allows it to playback "cinema quality" video. It can also store data in addition to audio and video tracks.
The current standard for DVD video is known in the industry as DVD-5, capable of storing 4.7GB (133 minutes of video) of data on a single side with a single layer. Emerging formats are capable of holding up to 17GB of data on both dual-layered sides. All DVD players are capable of playing back all formats. Recordable formats also exist, most notably DVD-R (which can be written once) and DVD-R/W (which can be written and erased hundreds of times).
DVD video is encoded as MPEG-1 (roughly VHS quality) or MPEG-2 (broadcast quality). Almost all consumer DVD products utilize MPEG-2, which allows data rates of up to 9.8 Megabits/sec and supports both 4:3 and 16:9 aspect ratios.
The DVD format utilizes Dolby AC3 Digital Surround Sound (in NTSC territories), can accommodate up to 32 subtitle tracks, eight different audio tracks (e.g., different languages), and nine different camera angles. It also features a menu-driven interface that allows access to various additional data, whether that resides on disc or online. DVD has a pixel resolution of 720 x 480 and, depending on the monitor and connection, can reproduce 500 horizontal scan lines (vs. VHS’s 240). DVD players are currently available for as little as $400.
DVD Authoring
Professional systems include Sonic Solutions’ DVD Creator and Daikin’s Scenarist, both outstanding and exorbitantly expensive (starting at around $100,000). New systems from Spruce Technologies and Astarte promise to bring the cost of DVD production out of the stratosphere. Spruce’s DVDMaestro ($49,950) [www.spruce-tech.com] is a professional-quality NT-based system that does it all at about a third of what you’d expect to pay for a turnkey authoring solution. Astarte’s DVDDirector [www.astarte.de] offers a stripped-down but very useful MPEG-2 encoding solution for the Mac for about $5,000. Heuris’ MPEGPower Professional-DVD [www.heuris.com], meanwhile, is a software encoder that can turn your Avid or Media 100 files into MPEG-2 for about $2,500.