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Can someone recommend a capture card?

Posted: Tue Jan 24, 2006 8:53 pm
by Simon
Hello,

I have been using Zone Minder for about 4 months now and I really love it. I would like to beef up my system a bit and I think a new capture card is in order. I am currently using an Impact VCB with two cameras. However, I only get 320x200 at 5fps per camera. I would like to find a capture card that meets the following specs:

- 4 channels or more (bnc connectors prefered)
- up to 30fps per channel
- higer resolution (640x480 or higher)

I was also wondering if there are capture cards with hardware encoding that won't tax the system as much as these basic frame grabbers that can be used with Linux and Zone Minder?

Thanks.

Posted: Tue Jan 24, 2006 9:04 pm
by jameswilson
Phil has some excellent cards for sale in the zm shop that have a chip per input (30fps per channel)

PS if you find a card that will capture full ress ie 640x480 without interlace issues id love to hear about it. Im still on the search mate lol

James

Posted: Wed Jan 25, 2006 2:35 pm
by Simon
jameswilson wrote:Phil has some excellent cards for sale in the zm shop that have a chip per input (30fps per channel)

PS if you find a card that will capture full ress ie 640x480 without interlace issues id love to hear about it. Im still on the search mate lol
Hey James,

Thats for the recommendation! This card looks great and I am going to purchase one directly from the manufacturer in the states since I am located in Canada.

Out of curosity whats the interlace issue you speak of?

Posted: Wed Jan 25, 2006 2:39 pm
by Simon
One question aboout the ituner Spectra8 card, on the web site it seems to indicate that using the optional 4 port expansion module will require "custom software" to be developed using the SDK:

http://www.ituner.com/spectra.htm

Last paragraph before the bulleted points:
Using an additional PCI expansion card, the Spectra8 video frame grabber card will allow you to capture from 8 simultaneous video inputs. However, when used in this mode, the FPS per channel will decrease to 10-15. You must have develop custom software in order to do capture video from 8 inputs, SDK provided.
Wondering if I should go ahead and order the expansion bracket or not. If I cannot use all 8 ports with Zone Minder then I won't bother with the expansion bracket.

Thanks.

Posted: Wed Jan 25, 2006 6:52 pm
by cordel
If you want 30 fps per input then don't get the expansion. Other wise the expansion uses the second input on each chip so effectively you would only get about 13 fps for each input since each chip can only do 30 fps total.

Yes ZM can use the additional inputs if you should chose to get the expansion bracket.

Corey

Posted: Thu Jan 26, 2006 12:33 am
by zoneminder
The expansion card works fine under Linux, I think it's just Windws drivers have to be specific. You do split the chip between the two inputs though, so it's go down to about 10fps for any shared ones. More than enough for most tasks still though.

Posted: Sat Feb 04, 2006 6:39 pm
by Simon
So I got my Spectra 8 card and I must say I am impressed. Using the ImpactVCB with two inputs was killing my box, and the zmc process was eating about 30-40% CPU. With the Spectra 8 the zmc process only sits around 4.9%! Wow.

I have one issue however, I was originally capuring at 320x240 with the RGB24 palette on the ImpactVCB. This configuration works fine on the Spectra 8 too. However, I wanted more resolution so bumped both cameras up to 640x480. At this point there was no capturing being done. I found that if I switched to Grey everything worked as it should and the card will let me capture at any resolution. Does anyone know why I can't capture at 640x480 with the RGB24 palette? I have tried the other palettes as well and the only one that works at 640x480 is Grey.

The other interesting thing is Zoneminder reports that both cameras are capturing at 40fps. Quite an upgrade from the less than 5 fps I was getting with the ImpactVCB.

Thanks.

Posted: Sat Feb 04, 2006 6:44 pm
by Simon
I should also mention I am using the following in my /etc/modules file under Ubuntu:

bttv card=42,42,42,42 radio=0 tuner=4 sloppy=1 chroma_agc=1 mmap=1 vbibufs=4 v4l2=1 gbuffers=16

This is the line that is in the Spectra 8 manual, so I copied it verbatim.

Thanks.

Posted: Sat Feb 04, 2006 6:56 pm
by Simon
Okay, I'm a putz. I should have used the search function before posting, so I will go ahead and answer my own message.

As someone pointed out it has to do with shared memory which can be altered by modifying sysctl.conf. You can find all the details here:

http://www.zoneminder.com/forums/viewto ... t=spectra8

This solution works just dandy on my Ubuntu system as well.

Thanks.