Mailing List archive
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[vdr] Re: [linux-dvb] OT: a rant regarding DVB-C cards
Hi Juha,
One possible argument in favour of full featured cards, is that you don't
*have* to use the tv-out to still be able to use the mpeg2 decoding
capabilities.
So you could set up a cheap video card with tv-out, and write a VDR driver
which is not much more than an xvideo overlay window (fullscreen), grabbing
decoded frames from the video4linux device (just as if it were grabbing video
with a normal analogue capture card) and blit it to the xvideo window.
Trivial to overlay the OSD, and you won't see the video corruption when
having the OSD on because it is added afterwards and not by the ARM.
If you have 2 cards for example, you can have picture-in-picture by simply
grabbing from 2 video4linux devices and blitting them in whichever way you
want, requiring very little CPU.
Then you are of course free to play games using the TV as well, and play divx
or whatever movies without having to transcode. DVD's use the mpeg2 decoder
of course. Picture-in-picture with nelonen in the corner while watching a DVD
would be possible for example.
Some cards are very expensive (i.e. Hauppauge one at Verkkokauppa.com :-) and
only offer composite, but the Siemens for example has composite, s-video and
RGB. Depends on the card.
CI modules is a tricky area, at this point it's easier to decide what you
intend to watch, what you need, and then (if possible) conclude which card /
driver will support that.
Not much choice in Finland unfortunately, I ordered mine from a friendly guy
in Germany :-)
By the way, these are Siemens cards, advertised as only able to do QAM-64, but
with some undocumented (read, lucky :)) register values it will happily do
QAM-128 also. The actual chip used for the decoding (ves1820) can do up to
QAM-256, so I am not sure why Siemens decided to change their minds and not
support > QAM-64. Mine work just fine with HTV. Needs finetuning though (of
several values used by the cards hardware) which is pretty much
trial-and-error. But at least it will work.
Cheers,
Dennis
--
Info:
To unsubscribe send a mail to listar@linuxtv.org with "unsubscribe vdr" as subject.
Home |
Main Index |
Thread Index