/dev/v4l vs /dev/video0

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timgman
Posts: 46
Joined: Wed Mar 14, 2007 6:01 pm

/dev/v4l vs /dev/video0

Post by timgman »

I have another linux based DVR package installed.......
devsec aka google codes "idvr".
My devices are 4 channel bttv's with 1 8X8 chip ...
(your standard "pico" card....

My devices are listed as /dev/video0 and /dev/video1
how do I access the other channels on these devices?
is there a standard linux v4l syntax?
like /dev/video0 channel=1?
or so on tghanks in advance./timg

Here's another post I've put out there on the subject......
OK, here's the verdict.
All 8 inputs are functional in Zoneminder...
On the Zoneminder 1.22.x live cd (kernel 2.6.16.xxxx mandrake based) my /dev has the same thing....

/dev/video0 my generic bttv pico card
/dev/video1 my avermedia bttv card.

Both of the 120 fps variety.....
The Zoneminder interface allows me to connect a camera to /dev/video0 channel 0 (or channel 1,2,3)

And I also have /dev/video1 cnannel 0(or channel 1,2,3)

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
(I think sharing the bt878 chip breaks it into sub devices... called channels........all four channels share one conextant bt878 fusion chip)

I'll bet that devsec sees all the chips as one channel on the higher end cards as the better cards have 1 chip per channel.



......So the syntax for the device in my /ust/lib/dt...whatever...../camera1.conf
needs to look like whatever the device ZM is pulling from....
perhaps /dev/video0,channel=0 or so.

Provided that Mpeg4ip has the ability to hit that v4l "sub device".


Thanks for that pointer James, I'm going to try and get the web part going in the next day or so.
awesome. Rock On!!!!!
.. thanks guys.
timg
timgman
Posts: 46
Joined: Wed Mar 14, 2007 6:01 pm

Here's some sparce info I've found.........

Post by timgman »

http://lists.mplayerhq.hu/pipermail/ffm ... 00406.html



interesting explanation of the "4 ports from 1 chip issue.......
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