GNOME Bugzilla – Bug 618850
Gstreamer Teletext decoder
Last modified: 2011-05-23 13:09:19 UTC
Created attachment 161208 [details] make dist This decoder allows decoding of teletext streams from DVB sources. When used unparametrised; the subtitles should be picked up. Pango can be used to get an approximation of a decoded teletext page (the difficulty is mapping the TT gfx characters to an approx in UTF8). gst-launch dvbsrc adapter=0 frequency=11567000 symbol-rate=22000 polarity=v ! mpegtsdemux program-number=9019 ! textrender ! ffmpegcolorspace ! autovideosink
Created attachment 161209 [details] fix for company based submission rules (barco.com domain name)
Sorry, the command line example is incorrect; gst-launch dvbsrc adapter=0 frequency=11567000 symbol-rate=22000 polarity=v ! mpegtsdemux program-number=9019 ! barcoteletextdec tt-all=True tt-page=100 tt-pango=True ! textrender ! ffmpegcolorspace ! autovideosink without parameters; it will default to the subtitles present in the pages. tt-interval re-sends the pages after a timeout on the network.
Test with http://crichton.homelinux.org/~marc/downloads/tt.gdp.gz gst-launch filesrc location=./tt.gdp ! gdpdepay ! barcoteletextdec tt-all=True tt-page=100 tt-pango=True ! textrender font-desc="Courier" ! ffmpegcolorspace ! autovideosink
A patch against gst-plugins-bad would be nice :)
Can not make it working with TS file (dvb subtitling). Marc, could you please tell me whether you tested subtitles within TS files?
The tests have been done on DVB-T (Flanders) DVB-S (FTA bundle with Rai, tunesian TV, Arte, ..) DVB-S (FTA bundle from ARD)
I'm trying to use ts file as follows, maybe I'm wrong with something? #gst-launch filesrc location=/home/alex/Devel/TEST_TS/tvwithsubtitles.ts ! mpegtsdemux ! barcoteletextdec ! textrender ! ffmpegcolorspace ! autovideosink Setting pipeline to PAUSED ... Pipeline is PREROLLING ... Pipeline is PREROLLED ... Setting pipeline to PLAYING ... New clock: GstSystemClock Got EOS from element "pipeline0". Execution ended after 188411 ns. Setting pipeline to PAUSED ... Setting pipeline to READY ... Setting pipeline to NULL ... Freeing pipeline ... Any help will be appreciated.
Ah, but you are doing something different. This module decodes teletext data; your subtitles might be in a different form in the TS. Are you certain you have a private/teletext type stream in your TS? Try gst-launch filesrc location=/home/alex/Devel/TEST_TS/tvwithsubtitles.ts ! mpegtsdemux ! private/teletext ! fakesink dump=1 to see if you get data from this.
Yes, I get this data. But this plugin is able to handle teletext data, not x-dvbsub (dvb subtitles), right?
Is "private/teletext" a good mime? Shouldn't it be "application/x-teletext" (I am asking because I am about to use another similar mime name)
I took the private/teletext because it is the mime type I get from mpegtsdemux; and it should take that as input. AFAIK, it's the analog stream simply multiplexed in the TS.
> Is "private/teletext" a good mime? Shouldn't it be "application/x-teletext" (I > am asking because I am about to use another similar mime name) We should probably change this to something like application/x-teletext or application/x-mpegts-teletext or something (is the standard MPEG specific?) if we intend to add plugins for it. private/foo should be more of a placeholder IMHO.
k. If it is changed in mpegtsdemux where the data is received from (in my case); I'll add/change it. It would also avoid the confusion about the bitmap subtitles.
How is this related to bug #619739?
It's a different implementation. I was not aware of the work of Andoni when I started out; hence submitted it. Andoni submitted a couple weeks later IIRC. We both started from the same base; and while I integrated tt support in the module itself (parsing code); Andoni fixed libzvbi support. Functionality wise; since zvbi is used; in bug #619739, an image buffer with correct decoding can be shown; while this decoder only approximates the mosaic fonts in UTF. Once the work in progress of bug #619739 (pango support); that decoder will have all and more functionality than this decoder (txt, html, pango and img).
> How is this related to bug #619739? if this bug is implemented; this one can be dropped; it's just another implementation; so no need in adding two doing the same.
I have it done in bug #619739. Can you test it, please?
Thanks for the bug report. This particular bug has already been reported into our bug tracking system, but please feel free to report any further bugs you find. *** This bug has been marked as a duplicate of bug 619739 ***