A term, usually found in filenames, referring to a particular style of DVD ripping. The term 'XDVD' is also used to refer to a CD-R containing an XDVD avi file. Such a CD-R usually contains the install files for the codec used to compress the XDVD as well. When used as part of a filename, the accepted forms are:
- Name of Movie (XDVD).avi (for movies encoded using the DivX ;-) codec)
- Name of Movie (XDVD).wmv (for movies encoded using Microsoft Windows Media 8 tools)
- Name of Series - Episode 01 (XDVD).avi
- Name of Universe - Name of Series - Episode 01 (XDVD).avi
- Name of Movie (XDVD) (Part 1 of 2).avi
Legal Note: The legality of XDVDs, and DVD rips in general, is unclear. My interpretation of relevant legal statutes is as follows: Using decss-like programs is legal. The studios agree that personal home taping is legal. Whether courts will extend the VHS-to-VHS quid pro quo to encompass DVD-to-CD remains to be seen. Of significance is that nothing currently protects second-hand copying in the case one is unable to copy the rented material oneself, which is the intended use-case for distributing XDVDs to others. The No Electronic Theft Act suggests that one may rip, distribute, or download up to 40 movies (or so) every six months, regardless of other right, without such activity being considered criminal. The preceeding may not be considered legal advice of any sort, and has not been evaluated by any legal professional.
Use of the moniker 'XDVD' asserts that several principles were followed in in a movie's creation. The following text is adapted from a readme file which one found along with some of the earliest XDVDs.
Nothing besides the MPEG4 codec (usually the DivX ;-) codec)and a video player such as Microsoft's Media Player should be required to view the movie. Thus, subtitled movies will have the subtitles as part of the video track.
The movies are usually encoded with 512 pixels of horizontal resolution. The reason for this choice is twofold: the video is perfect for display on a standard television using tv-out or projector hardware, and may be rendered pixel-doubled on a 1024x768 display with the minimum image distortion and CPU overhead possible. It also happens to be an excellent size for most movies in terms of the quality which can be obtained given the 700 MB filesize limit.
Occasionally, it is possible to preserve the original's 720 pixel horizontal dimension while maintaining the quality and filesize standards of XDVD, especially with the advent of variable encoding techniques. This practice is acceptable.
Whether the original was anamorphic, widescreen, or full frame, the XDVD should match the film's intended display aspect as closely as possible. Any black bars (letterboxing) should be eliminated. Restrictions on the height of MPEG-encoded video result in a few extra black pixels on some films.
One of the results of this principle is that a full-frame movie will have up to twice as much information per frame as a 2.4:1 super-widescreen film. As a result, widescreen movies tend to look a bit better.
An XDVD should be encoded to maximize the amount of space
used on a standard 700 MB CD-R. This is to facilitate building a personal home video library, as when one copies rented VHS movies for personal use. The studios don't seem to mind if you have a copy of a movie you've rented for your own use, and you can even lend it to a friend. (However, you have no legally granted right to do so — see the legal note above.) So it should be fine if you copy an XDVD of a movie you've rented in the past but couldn't copy yourself. You can also borrow someone else's XDVD, even if you haven't rented that movie before. Get it? (please /msg me if this explanation is still confusing.)
Some unusually long- or action-packed movies, or those whose audio track is largely symphonic, will be encoded in two parts, usually broken on a chapter boundary from the original DVD, each filling a CD-R.
When the maker of a particular XDVD cares about the subject more than usual, one might put much effort into combining multiple encodings to get the best mix of overall detail and quality fast-moving scenes. These XDVDs will sometimes have 'V.E.' (for variable encoding) or something similar in their filenames as well.
One exception to these guidelines is anime, especially DVDs which compile television series like Evangelion or Trigun. Several features of Japanese-style animation, and the way they encode their DVD video, make it particularly hard to compress efficiently with current MPEG4 encoders. The hard outline edges between shapes causes the same problems as with JPEG. The impact of full-frame video has already been mentioned. More insidious is the impact the large jumps contours and objects make from frame to frame in animation -- changes much larger that of the smooth motion of natural objects the encoder's motion compensation routines are good at. Also, especially for TV series, interlacing artifacts are often present and impossible to eradicate completely, resulting in extraneous detail (the interlaced lines) on which the encoder wastes much bandwidth. Usually, acceptable quality can be achieved only by limiting the length of each disc to an hour at most. Individual episodes are always encoded in separate files. Thus, the intention is usually that one will burn two episodes per CD-R.