Text capture: Difference between revisions
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==Applications== |
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* alevtv |
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* gstreamer |
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* ntsc-cc |
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* tvtime |
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* zvbi |
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===gstreamer=== |
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The application gstreamer has incorporated support for closed captioning (they also mention some tweaks for Canadian English and French television); see [http://cvs.freedesktop.org/gstreamer/gst-plugins/gst/vbidec/ Freedesktop's repository]. |
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===ntsc-cc=== |
===ntsc-cc=== |
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The application ntsc-cc handles closed captioning on [[bttv devices]]. For ntsc-cc to work, you typically need to be running an application for viewing or recording television, such as xawtv and mencoder. If no such application is running, ntsc-cc tends to produce garbled output. |
The application ntsc-cc handles closed captioning on [[bttv devices]]. For ntsc-cc to work, you typically need to be running an application for viewing or recording television, such as xawtv and mencoder. If no such application is running, ntsc-cc tends to produce garbled output. |
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===tvtime |
===tvtime=== |
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tvtime has built-in support for closed captioning for [[bttv devices | bttv]] and [[saa7134 devices | saa7134]] cards (also other?). |
tvtime has built-in support for closed captioning for [[bttv devices | bttv]] and [[saa7134 devices | saa7134]] cards (also other?). |
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In early 2004, Kevin Ko wrote a [http://www.princeton.edu/~kko/tvtime/vbi_lock_0.2.patch patch with useful comments] to tvtime's vbidata.c; see [http://www.princeton.edu/~kko/tvtime/ his detailed account] and [https://sourceforge.net/tracker/?func=detail&atid=506989&aid=884449&group_id=64301 the tvtime bugreport]. |
In early 2004, Kevin Ko wrote a [http://www.princeton.edu/~kko/tvtime/vbi_lock_0.2.patch patch with useful comments] to tvtime's vbidata.c; see [http://www.princeton.edu/~kko/tvtime/ his detailed account] and [https://sourceforge.net/tracker/?func=detail&atid=506989&aid=884449&group_id=64301 the tvtime bugreport]. |
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==Unsupported cards== |
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There is currently no code supporting closed captioning on cx88 cards. |
There is currently no code supporting closed captioning on cx88 cards. |
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Revision as of 07:18, 22 April 2005
The PAL standard uses teletext, while the NTSC standard uses closed captioning. TV capture chipsets implement these in different ways, and the code to support text capture is still missing or incomplete on some chipsets. Finally, different applications implement support in different ways. The following notes are just a start to describe the current state of affairs.
Applications
- alevtv
- gstreamer
- ntsc-cc
- tvtime
- zvbi
gstreamer
The application gstreamer has incorporated support for closed captioning (they also mention some tweaks for Canadian English and French television); see Freedesktop's repository.
ntsc-cc
The application ntsc-cc handles closed captioning on bttv devices. For ntsc-cc to work, you typically need to be running an application for viewing or recording television, such as xawtv and mencoder. If no such application is running, ntsc-cc tends to produce garbled output.
tvtime
tvtime has built-in support for closed captioning for bttv and saa7134 cards (also other?).
In early 2004, Kevin Ko wrote a patch with useful comments to tvtime's vbidata.c; see his detailed account and the tvtime bugreport.
Unsupported cards
There is currently no code supporting closed captioning on cx88 cards.