VOB

Last updated
VOB
Filename extension
.vob, .ifo, .bup
Internet media type
video/dvd, video/mpeg, [1] [2] video/x-ms-vob[ citation needed ]
Developed by DVD Forum
Type of format Container format
Container for Audio, video, subtitles
Contained by DVD-Video
Extended from MPEG program stream (ISO/IEC 13818-1)
Standard DVD-Video Book [3] [4]
Open format?No
Free format?No

VOB (for video object) is the container format in DVD-Video media. VOB can contain digital video, digital audio, subtitles, DVD menus and navigation contents multiplexed together into a stream form. Files in VOB format may be encrypted.

Contents

File format

Files in VOB format have a .vob filename extension and are typically stored in the VIDEO_TS directory at the root of a DVD. [5] The VOB format is based on the MPEG program stream format, but with additional limitations and specifications in the private streams. [6] [7] [8] The MPEG program stream has provisions for non-standard data (as used in VOB files) in the form of so-called private streams. VOB files are a very strict subset of the MPEG program stream standard. While all VOB files are MPEG program streams, not all MPEG program streams comply with the definition for a VOB file. [6]

Analogous to the MPEG program stream, a VOB file can contain H.262/MPEG-2 Part 2 or MPEG-1 Part 2 video, MPEG-1 Audio Layer II or MPEG-2 Audio Layer II audio, but usage of these compression formats in a VOB file has some restrictions in comparison to the MPEG program stream. In addition, a VOB file can contain linear PCM, AC-3 or DTS audio and subpictures (subtitles). [7] [9] [10] VOB files cannot contain AAC audio (MPEG-2 Part 7), MPEG-4 compression formats and others, which are allowed in the MPEG program stream standard.[ citation needed ]

On the DVD, all of the content for one title set is contiguous, but if necessary is broken up into 1 GB VOB files in order to be compatible with all operating systems, as some cannot read files larger than that size. [6] [11]

Companion files

VOB files may be accompanied with IFO and BUP files. These files respectively have .ifo and .bup filename extensions.

IFO (information) files contain all the information a DVD player needs to know about a DVD so that the user can navigate and play all DVD content properly, [12] such as where a chapter starts, where a certain audio or subtitle stream is located, information about menu functions and navigation. BUP (backup) files are exact redundant copies of IFO files, supplied to help in case of corruption. Video players may not allow DVD navigation when IFO or BUP files are absent.

Copy protection

Almost all commercially produced DVD-Video titles use some restriction or copy protection method, which also affects VOB files. [13] Copy protection is usually used for copyrighted content.

Many DVD-Video titles are encrypted with Content Scramble System (CSS). This is a data encryption and communications authentication method designed to prevent copying video and audio data directly from the DVD-Video discs. Decryption and authentication keys needed for playing back encrypted VOB files are stored in the normally inaccessible lead-in area of the DVD and are used only by CSS decryption software (e.g., in a DVD player or software player). If someone is trying to copy the contents of an encrypted DVD-Video (e.g., VOB files) to a hard drive, an error can occur, because the DVD was not authenticated in the drive by CSS decryption software. Authentication of the disc allows the copying of individual VOB files without error, but the encryption keys will not be copied. If the copied undecrypted VOB files are opened in a player, they will request the keys from the DVD-ROM drive and will fail. [14] [15] There are many CSS-decrypting programs, or ripping software, such as libdvdcss, DeCSS, DVD Decrypter, AnyDVD or DVD Shrink which allow a protected DVD-Video disc to be played without access to the original key or copied to hard disk unscrambled. In some countries, their usage can be a violation of law (e.g. for non-personal use). [15]

Playback

A player of generic MPEG-2 files can usually play unencrypted VOB files, which contain MPEG-1 Audio Layer II audio. Other audio compression formats such as AC-3 or DTS are less widely supported.[ citation needed ]

KMPlayer, VLC media player, GOM player, Media Player Classic and more platform-specific players like ALLPlayer play VOB files.

Other DVD containers

Some DVD Recorders use DVD-VR format and store multiplexed audiovisual content in VRO containers. [16] [17] A VRO file is equivalent to a collection of DVD-Video VOB files. The VRO files can be played directly like a VOB if no editing is intended. [18] Fragmented VRO files are not widely supported by software players and video editing software. [16]

Enhanced VOB (EVO) is also an extension to VOB, originally meant for the now-discontinued HD DVD video. It can contain additional video and audio formats such H.264 and AAC.

See also

Related Research Articles

<span class="mw-page-title-main">DVD-Audio</span> DVD format for storing high-fidelity audio

DVD-Audio is a digital format for delivering high-fidelity audio content on a DVD. DVD-Audio uses most of the storage on the disc for high-quality audio and is not intended to be a video delivery format.

<span class="mw-page-title-main">VideoLAN</span> Non-profit organization developing software

VideoLAN is a non-profit organization which develops software for playing video and other media formats. It originally developed two programs for media streaming, VideoLAN Client (VLC) and VideoLAN Server (VLS), but most of the features of VLS have been incorporated into VLC, with the result renamed VLC media player.

<span class="mw-page-title-main">VLC media player</span> Free and open-source media-player and streaming-media-server

VLC media player is a free and open-source, portable, cross-platform media player software and streaming media server developed by the VideoLAN project. VLC is available for desktop operating systems and mobile platforms, such as Android, iOS and iPadOS. VLC is also available on digital distribution platforms such as Apple's App Store, Google Play, and Microsoft Store.

Ripping is extracting all or parts of digital content from a container. Originally, it meant to rip music out of Commodore 64 games. Later, the term was used to mean to extract WAV or MP3 format files from digital audio CDs, but got applied as well to extract the contents of any media, including DVD and Blu-ray discs, and video game sprites.

<span class="mw-page-title-main">DVD Shrink</span> Optical disc authoring software

DVD Shrink is a freeware DVD transcoder program for Microsoft Windows that uses a DVD ripper to back up DVD video. The final versions are 3.2.0.15 (English) and 3.2.0.16 (German); all other versions, such as DVD Shrink 2010, are illegitimate. DVD Shrink's purpose is, as its name implies, to reduce the amount of data stored on a DVD with minimal loss of quality, although some loss of quality is inevitable. It creates a copy of a DVD, during which the DVD region code is removed, and copy protection may also be circumvented. A stamped DVD may require more space than is available on a writeable DVD, unless shrunk. Many commercially released video DVDs are dual layer ; DVD Shrink can make a shrunk copy which will fit on a single-layer writeable DVD, processing the video with some loss of quality and allowing the user to discard unwanted content such as foreign-language soundtracks.

Nero Digital is a brand name applied to a suite of MPEG-4-compatible video and audio compression codecs developed by Nero AG of Germany and Ateme of France. The audio codecs are integrated into the Nero Digital Audio+ audio encoding tool for Microsoft Windows, and the audio & video codecs are integrated into Nero's Recode DVD ripping software.

The following comparison of video players compares general and technical information for notable software media player programs.

TMPGEnc or TSUNAMI MPEG Encoder is a video transcoder software application primarily for encoding video files to VCD and SVCD-compliant MPEG video formats and was developed by Hiroyuki Hori and Pegasys Inc. TMPGEnc can also refer to the family of software video encoders created after the success of the original TMPGEnc encoder. These include: TMPGEnc Plus, TMPGEnc Free Version, TMPGenc Video Mastering Works, TMPGEnc Authoring Works, TMPGEnc MovieStyle and TMPGEnc MPEG Editor. TMPGEnc products run on Microsoft Windows.

cDVD discs, also known as mini-DVD discs, are regular data CDs that contain MPEG-2 or MPEG-1 video structured in accordance with the DVD-Video specifications.

These tables compare features of multimedia container formats, most often used for storing or streaming digital video or digital audio content. To see which multimedia players support which container format, look at comparison of media players.

Flash Video is a container file format used to deliver digital video content over the Internet using Adobe Flash Player version 6 and newer. Flash Video content may also be embedded within SWF files. There are two different Flash Video file formats: FLV and F4V. The audio and video data within FLV files are encoded in the same way as SWF files. The F4V file format is based on the ISO base media file format, starting with Flash Player 9 update 3. Both formats are supported in Adobe Flash Player and developed by Adobe Systems. FLV was originally developed by Macromedia. In the early 2000s, Flash Video was the de facto standard for web-based streaming video. Users include Hulu, VEVO, Yahoo! Video, metacafe, Reuters.com, and many other news providers.

<span class="mw-page-title-main">KMPlayer</span> Freeware media player for Microsoft Windows

K-Multimedia Player is an Adware-supported media player for Windows and iOS that can play most current audio and video formats, including VCD, HDML, DVD, AVI, MKV, Ogg, OGM, 3GP, MPEG-1/2/4, AAC, WMA 7, 8, WMV, RealMedia, FLV and QuickTime. KMPlayer shows many advertisements, including in the homepage, side panels, options panel, and as pop-up ads.

Program stream is a container format for multiplexing digital audio, video and more. The PS format is specified in MPEG-1 Part 1 and MPEG-2 Part 1, Systems. The MPEG-2 Program Stream is analogous and similar to ISO/IEC 11172 Systems layer and it is forward compatible.

The DVD-VR standard defines a logical format for video recording on DVD-R, DVD-RW, and DVD-RAM style media, including the dual layer versions of these media. As opposed to media recorded with the DVD+VR recording standard, the resulting media are not DVD-Video compliant, and do not play back in some DVD-Video players. Most DVD video recorders in the market that support DVD-R, DVD-RW, or DVD-RAM media record to these media in DVD-VR mode, as well as in a DVD-Video compliant mode. It is possible to use the DVD-VR format with DVD+R and DVD+RW media, but no examples are known other than some PC based recording utilities.

<span class="mw-page-title-main">Advanced Access Content System</span> Standard for content distribution and digital rights management

The Advanced Access Content System (AACS) is a standard for content distribution and digital rights management, intended to restrict access to and copying of the post-DVD generation of optical discs. The specification was publicly released in April 2005. The standard has been adopted as the access restriction scheme for HD DVD and Blu-ray Disc (BD). It is developed by AACS Licensing Administrator, LLC, a consortium that includes Disney, Intel, Microsoft, Panasonic, Warner Bros., IBM, Toshiba and Sony. AACS has been operating under an "interim agreement" since the final specification has not yet been finalized.

Enhanced Video Object, also known as Enhanced VOB, EVOB or EVO, is a container format for HD DVD video media. It contains the actual digital video, digital audio, subtitle and DVD menu contents in stream form. It is an extension to VOB. It can contain video encoded in H.264/MPEG-4 AVC, VC-1, or H.262/MPEG-2 Part 2 and audio encoded in AC-3, E-AC-3, Dolby TrueHD, DTS, DTS-HD, PCM, and MPEG-2 Part 3.

.m2ts is a filename extension used for the Blu-ray disc Audio-Video (BDAV) MPEG-2 Transport Stream (M2TS) container file format. It is used for multiplexing audio, video and other streams, such as subtitles. It is based on the MPEG-2 transport stream container. This container format is commonly used for high definition video on Blu-ray Disc and AVCHD.

The Content Scramble System (CSS) is a digital rights management (DRM) and encryption system employed on many commercially produced DVD-Video discs. CSS utilizes a proprietary 40-bit stream cipher algorithm. The system was introduced around 1996 and was first compromised in 1999.

<span class="mw-page-title-main">DVD-Video</span> Format used to store digital video on DVD discs

DVD-Video is a consumer video format used to store digital video on DVD discs. DVD-Video was the dominant consumer home video format in Asia, North America, Europe, and Australia in the 2000s until it was supplanted by the high-definition Blu-ray Disc. Discs using the DVD-Video specification require a DVD drive and an MPEG-2 decoder. Commercial DVD movies are encoded using a combination of MPEG-2 compressed video and audio of varying formats. Typically, the data rate for DVD movies ranges from 3 to 9.5 Mbit/s, and the bit rate is usually adaptive. DVD-Video was first available in Japan on November 1, 1996, followed by a release on March 24, 1997 in the United States—to line up with the 69th Academy Awards that same day.

<span class="mw-page-title-main">MPEG Video Wizard DVD</span>

MPEG Video Wizard DVD, also known as MVW-DVD, is a non-linear video editing software developed by Womble Multimedia, Inc.. It allows users to edit video content, create DVDs with menus and then burn them without the need for any additional software.

References

  1. ↑ "VOB File Format". WhatIs.com. TechTarget. Retrieved 18 April 2012.
  2. ↑ ".VOB File". FileExt. UniBlue. Retrieved 18 April 2012.
  3. ↑ DVD FLLC (2009-02) DVD Book Construction - list of all available DVD Books, Retrieved on 2009-07-24
  4. ↑ DVD FLLC DVD Format Book - History of Supplements for DVD Books, Retrieved on 2009-07-24
  5. ↑ ".VOB File Extension". FileInfo.com. Retrieved 18 April 2012.
  6. 1 2 3 "What is a VOB file". MPUCoder. SoundWare Associates. Retrieved 18 April 2012.
  7. 1 2 "DVD - MPeg (sic.) differences". DVD Resources for Open Source Development. SourceForge . Retrieved 28 April 2012.
  8. ↑ "Is it easy to understand DVD format?". Archived from the original on 2001-10-24. Retrieved 2011-02-26.
  9. ↑ MPEG.org (July 21, 1996) DVD Technical Notes - Video Data Specifications, Retrieved on 2009-07-25
  10. ↑ Videohelp.com What is DVD? Technical Info for DVD-Video, Retrieved on 2009-07-28
  11. ↑ Doom9.org doom9.org What's on a DVD?, Retrieved on 2009-07-26
  12. ↑ AfterDawn.com (2007-07-31) How to play VOB / IFO / BUP files, Retrieved on 2009-07-26
  13. ↑ DVD Demystified (July 13, 2009) What are the copy protection issues?, Retrieved on 2009-07-28
  14. ↑ DVD Demystified (July 13, 2009) DVD Frequently Asked Questions (and Answers) - Why can't I play movies copied to my hard drive?, Retrieved on 2009-07-28
  15. 1 2 What are the copy protection schemes used in DVD ? What is CSS ?, Retrieved on 2009-07-28
  16. 1 2 DVD Demystified (July 13, 2009) What are .IFO, .VOB, .AOB, and .VRO files? How can I play them?, Retrieved on 2009-07-28
  17. ↑ Doom9's forum (2002-2005) DVD-RAM *.VRO File Conversion, Retrieved on 2009-07-28
  18. ↑ DVD-VR Application format notes, Retrieved on 2009-07-28
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.