Universal Subtitle Format (USF) is a CoreCodec project to create a clean, documented, powerful and easy to use subtitle file format. It is based on XML

XML

Extensible Markup Language is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards....

 for some of the following reasons: flexibility, unicode support, a hierarchical system, and ease of administration.

USF subtitles are usually used in Matroska

Matroska

The Matroska Multimedia Container is an open standard free container format, a file format that can hold an unlimited number of video, audio, picture or subtitle tracks in one file. It is intended to serve as a universal format for storing common multimedia content, like movies or TV shows...

 Containers.

The format has come under criticism, especially from the fansub

Fansub

A fansub is a version of a foreign film or foreign television program which has been translated by fans and subtitled into a language other than that of the original.-History:...

 community, because compared to the format it aims to replace, Advanced Substation Alpha

SubStation Alpha

SubStation Alpha , abbreviated SSA, is a subtitle file format created by CS Low that allows for more advanced subtitles than the conventional SRT and similar formats. This format can be rendered with VSFilter in conjunction with a DirectShow-aware video player , or MPlayer with the SSA/ASS library...

 (which is based on comma-separated values

Comma-separated values

A comma-separated values file stores tabular data in plain-text form. As a result, such a file is easily human-readable ....

), it is more verbose and far harder for software to read, write and manipulate. It is also much harder to edit "by hand" in text editors such as notepad. For these reasons, as well as the lack of a generic cross-platform parsing/rasterizing library and mature editing programs that natively support it, the format has not gained wide acceptance.

No known media player software implements more than basic support for this format. VSFilter

VSFilter

DirectVobSub formerly known as VSFilter is a software add-on for Microsoft Windows that is able to read external subtitle files and superimposes them on a playing video file....

, and 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...

(starting with the 0.9.0 release) can extract the subtitle text, timing information and very restricted formatting.

Documentation for the format is now hosted by the Danish subtitling software company Titlevision here.

Example

Below is the example USF file as presented in the v1.1 specification:





[Toff]
christophe.paris@free.fr
http://christophe.paris.free.fr/

English
2002-11-08
This is a short example of USF.














Welcome to
The Core Media Player
colorkey="#FFFFFF">TCMP_Logo.bmp



Hi! This is a
small sample, let's sing a song.



La! La! La!
Karokeeeeeeeee is fun !