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Recording Subtitles with Linux

This site is dedicated to extracting subtitles from Teletext pages in PAL television transmissions under Linux. It has been developed because of the lack of commercial DVD-recorders that are able to capture Teletext pages along with the video data streams. The teletext pages are transmitted during the vertical blanking interval (VBI).

Subtitles are required for people with hearing difficulties, people wanting to learn a foreign language or people who can read a foreign language and not understand the language that a program has been transmitted. For example, BBC Prime transmits English programs in various countries and each of these programmes can have up to 10 subtitle languages.

There are various programs that can capture video streams from television cards including Freevo, MythTV and Zapping. The software available on this site is written for IVTV television cards running on a Linux system and can be freely used and distributed.

There are two methods to extract subtitle data from a transmission, either capture the subtitle stream as the program is being recorded (vbi2srt) or to extract the subtitles from a MPEG stream which has embedded Teletext data (vbiutil). This site also contains a command line utility (vbishow) that can be used to examine and analyse teletext transmissions and a test program (v4ltest) that can be used to testing video4linux interfaces.