RMVB
Encyclopedia
RealMedia Variable Bitrate (RMVB) is a variable bitrate
Variable bitrate
Variable bitrate is a term used in telecommunications and computing that relates to the bitrate used in sound or video encoding. As opposed to constant bitrate , VBR files vary the amount of output data per time segment...

 extension of the RealMedia
RealMedia
RealMedia is a proprietary multimedia container format created by RealNetworks. Its extension is ".rm". It is typically used in conjunction with RealVideo and RealAudio and is used for streaming content over the Internet....

 multimedia
Multimedia
Multimedia is media and content that uses a combination of different content forms. The term can be used as a noun or as an adjective describing a medium as having multiple content forms. The term is used in contrast to media which use only rudimentary computer display such as text-only, or...

 container format
Container format
A container or wrapper format is a meta-file format whose specification describes how different data elements and metadata coexist in a computer file....

 developed by RealNetworks
RealNetworks
RealNetworks, Inc. is a provider of Internet media delivery software and services based in Downtown Seattle, Washington, United States. The company is the creator of RealAudio, a compressed audio format; RealVideo, a compressed video format; RealPlayer, a media player; RealDownloader, a download...

.

As opposed to the more common RealMedia
RealMedia
RealMedia is a proprietary multimedia container format created by RealNetworks. Its extension is ".rm". It is typically used in conjunction with RealVideo and RealAudio and is used for streaming content over the Internet....

 container, which holds streaming media
Streaming media
Streaming media is multimedia that is constantly received by and presented to an end-user while being delivered by a streaming provider.The term "presented" is used in this article in a general sense that includes audio or video playback. The name refers to the delivery method of the medium rather...

 encoded at a constant bitrate
Constant bitrate
Constant bitrate is a term used in telecommunications, relating to the quality of service. Compare with variable bitrate.When referring to codecs, constant bit rate encoding means that the rate at which a codec's output data should be consumed is constant...

 (CBR), RMVB is typically used for multimedia content stored locally. Files using this format have the file extension ".rmvb".

RealMedia uses compression similar to MPEG-4 Part 10
H.264/MPEG-4 AVC
H.264/MPEG-4 Part 10 or AVC is a standard for video compression, and is currently one of the most commonly used formats for the recording, compression, and distribution of high definition video...

 codecs, such as x264
X264
x264 is a free software library for encoding video streams into the H.264/MPEG-4 AVC format. It is released under the terms of the GNU General Public License.-History:...

.

RMVB files are extremely popular for distributing Asian content, especially Chinese television episodes and movies. For this reason, they have become noticeably present (though not entirely popular, partly due to their incompatibility with other media players) on file sharing
File sharing
File sharing is the practice of distributing or providing access to digitally stored information, such as computer programs, multimedia , documents, or electronic books. It may be implemented through a variety of ways...

 platforms such as BitTorrent, eDonkey
EDonkey
eDonkey may refer to:* eDonkey network , a popular file sharing network** eDonkey2000, a discontinued file sharing program that used the eDonkey network...

 and Gnutella
Gnutella
Gnutella is a large peer-to-peer network which, at the time of its creation, was the first decentralized peer-to-peer network of its kind, leading to other, later networks adopting the model...

.

On the Windows
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...

 platform, the proprietary RealPlayer
RealPlayer
RealPlayer is a cross-platform media player by RealNetworks that plays a number of multimedia formats including MP3, MPEG-4, QuickTime, Windows Media, and multiple versions of proprietary RealAudio and RealVideo formats.-History:...

 SP and the open-sourced Media Player Classic
Media Player Classic
Media Player Classic is a compact media player for 32-bit and 64-bit Microsoft Windows. The application mimics the look and feel of the old, lightweight Windows Media Player 6.4 but integrates most options and features found in modern media players...

 support RMVB, using an appropriate DirectShow
DirectShow
DirectShow , codename Quartz, is a multimedia framework and API produced by Microsoft for software developers to perform various operations with media files or streams. It is the replacement for Microsoft's earlier Video for Windows technology...

 filter or Real Alternative. On Linux
Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...

 and other Unix-like
Unix-like
A Unix-like operating system is one that behaves in a manner similar to a Unix system, while not necessarily conforming to or being certified to any version of the Single UNIX Specification....

 platforms, MPlayer
MPlayer
MPlayer is a free and open source media player. The program is available for all major operating systems, including Linux and other Unix-like systems, Microsoft Windows and Mac OS X. Versions for OS/2, Syllable, AmigaOS and MorphOS are also available. The Windows version works, with some minor...

, xine
Xine
xine is a multimedia playback engine for Unix-like operating systems released under the GNU General Public License. xine is built around a shared library that supports different frontend player applications. Another important feature of xine is the ability to manually correct the synchronization...

, and Totem are able to play RMVB files using the open-source, reverse-engineered RMVB implementation in FFmpeg
FFmpeg
FFmpeg is a free software project that produces libraries and programs for handling multimedia data. The most notable parts of FFmpeg are libavcodec, an audio/video codec library used by several other projects, libavformat, an audio/video container mux and demux library, and the ffmpeg command line...

. The format is also supported for playback by the cross-platform VLC media player
VLC media player
VLC media player is a free and open source media player and multimedia framework written by the VideoLAN project.VLC is a portable multimedia player, encoder, and streamer supporting many audio and video codecs and file formats as well as DVDs, VCDs, and various streaming protocols. It is able to...

.

Identifying characters

The file header for the format consists of the four bytes ".RMF" (hex
Hexadecimal
In mathematics and computer science, hexadecimal is a positional numeral system with a radix, or base, of 16. It uses sixteen distinct symbols, most often the symbols 0–9 to represent values zero to nine, and A, B, C, D, E, F to represent values ten to fifteen...

 2E 52 4D 46), the same as the standard RealMedia
RealMedia
RealMedia is a proprietary multimedia container format created by RealNetworks. Its extension is ".rm". It is typically used in conjunction with RealVideo and RealAudio and is used for streaming content over the Internet....

 format.

See also

  • RealMedia
    RealMedia
    RealMedia is a proprietary multimedia container format created by RealNetworks. Its extension is ".rm". It is typically used in conjunction with RealVideo and RealAudio and is used for streaming content over the Internet....

  • RealVideo
    RealVideo
    RealVideo is a suite of proprietary video compression formats developed by RealNetworks – the specific format changes with the version. It was first released in 1997 and is at version 10. RealVideo is supported on many platforms, including Windows, Mac, Linux, Solaris, and several mobile...

     codecs
  • RealAudio
    RealAudio
    RealAudio is a proprietary audio format developed by RealNetworks and first released in April 1995. It uses a variety of audio codecs, ranging from low-bitrate formats that can be used over dialup modems, to high-fidelity formats for music. It can also be used as a streaming audio format, that is...

     codecs
  • Container format
    Container format
    A container or wrapper format is a meta-file format whose specification describes how different data elements and metadata coexist in a computer file....

  • Comparison of container formats
    Comparison of container formats
    This table compares features of container formats. To see which multimedia players support which container format, look at comparison of media players.-Information:-Audio formats supported:-Video formats supported:-Caption formats supported:...

  • Comparison of video player software
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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