SubRip

Using optical character recognition, SubRip can extract from live video, video files and DVDs, then record the extracted subtitles and timings as a Subrip format text file.[12] It can optionally save the recognized subtitles as bitmaps for later subtraction (erasure) from the source video.[13][14]

In practice, SubRip is configured with the correct codec for the video source, then trained by the user on the specific text area, fonts, styles,[15] colors and video processing requirements[16] to recognize subtitles. After trial and fine tuning, SubRip can automatically extract subtitles for the whole video source file during its playback. SubRip records the beginning and end times and text for each subtitle in the output text .srt file.[17]

SubRip uses AviSynth to extract video frames from source video, and can rip subtitles from all video files supported by that program.

The SubRip file format is described on the Matroska multimedia container format website as "perhaps the most basic of all subtitle formats."[18] SubRip (SubRip Text) files are named with the extension .srt, and contain formatted lines of plain text in groups separated by a blank line. Subtitles are numbered sequentially, starting at 1. The timecode format used is hours:minutes:seconds,milliseconds with time units fixed to two zero-padded digits and fractions fixed to three zero-padded digits (00:00:00,000). The fractional separator used is the comma, since the program was written in France.

1. A numeric counter identifying each sequential subtitle
2. The time that the subtitle should appear on the screen, followed by --> and the time it should disappear
3. Subtitle text itself on one or more lines
4. A blank line containing no text, indicating the end of this subtitle[18]

Example for Star Wars: Episode II – Attack of the Clones:

1
00:02:16,612 --> 00:02:19,376
Senator, we're making
our final approach into Coruscant.

2
00:02:19,482 --> 00:02:21,609
Very good, Lieutenant.

3
00:03:13,336 --> 00:03:15,167
We made it.

4
00:03:18,608 --> 00:03:20,371
I guess I was wrong.

5
00:03:20,476 --> 00:03:22,671
There was no danger at all.

In 1999, Brain created SubRip, and a friend, David Dolinski, created SubViewer, who offered it for download on his personal website.[32][33][34][35][36][37]

SubViewer was included in the DivX media player. On August 28, 2008, YouTube included support for SubViewer and SubRip, allowing existing videos to be retroactively subtitled.[33]

A format originally called WebSRT (Web Subtitle Resource Tracks) was specified in 2010 by the Web Hypertext Application Technology Working Group for the proposed HTML5 <track> element. It shared the .srt file extension and was based on parts of the SubRip format, but was not fully compatible with it.[38][39] The prospective format was later renamed WebVTT (Web Video Text Track).[40][41] Google's Chrome and Microsoft's Internet Explorer 10 browsers were the first to support <track> tags with WebVTT files for HTML5 videos. Mozilla Firefox implemented WebVTT in its nightly builds (Firefox 24), and as of Firefox 31 (July 24, 2014), Mozilla enabled WebVTT on Firefox by default.[42] YouTube began supporting WebVTT in April, 2013.[43]

• Closed captioning
• Timed text
• Comparison of video player software § Subtitle ability
• Avidemux
• List of free television software
• MicroDVD
• SubStation Alpha
• Universal Subtitle Format
• DirectVobSub – able to extract subtitles from a DVD without first extracting the files from it

• Related media at Wikimedia Commons:
  • Commons:Timed Text
  • Commons:Universal Subtitles
• Official website
• ".SRT SubRip file format specification". Doom9. Retrieved April 7, 2004. Derived from the SubRip source code