Technical format overview
The DVD-VR standard defines a logical format for recording and editing of video on a DVD disc. Instead of modifying the DVD Video standard, a separate standard was created to allow for this.
Video is recorded as an MPEG-2 program stream. Video resolution depends on the recording quality and the video format used. Multiple audio encodings are allowed including MPEG Audio, Dolby AC3 and Linear PCM.
A DVD-VR recorded disc contains a 'DVD_RTAV' directory in the root of the filesystem, in which a single 'VR_MOVIE.VRO' file exists, containing the raw audio and video data for all video recordings on the disc. The recording metadata along with navigation data to represent playlist,programs and so on are also stored in the 'VR_MANGR.IFO' file in the same directory. A backup copy of this file (VR_MANGR.BUP) typically is present as well.
The file system used on the media is UDF Revision 2.0. DVD-VR uses the realtime file extensions for UDF. For DVD-R media the VAT flavor is used, for DVD-RAM the plain flavor is used, and the spared flavor is used for DVD-RW media.
Packet writing technology is used to allow random access to, and incremental updating of the optical media.
In order to allow interchange between recorders, it may be necessary to finalize or protect DVD-RW media before putting these in another recording system. DVD-R media must be finalized before playback is possible in players. Also finalization may be required before a DVD-R disc can be accessed in another recording system.
