4 Way video Capture ..HW Question

[David Jones vpac org>]

Our system to be targeted for is a 4 way video capture system.
We want to simultaneously capture to disk (with hardware processing to say
MPEG 2 or 4 prior to saving to disk) 4 video inputs.
This is not a surveillance thing where 4 way PCI capture cards compose one
video stream from 4 by placing the camera contents in ¼ of the same
screen/image.

The system is meant to capture the 4 streams away from base over a long
period of time so its a performance v storage issue v power.

We could use a high performance PC with 4 PCI solots/video capture cards,
and a terrabyte or two of storage but that is not practical.

We are thinking of using a moderate capability PC (say mini ITX 1.3-1.7GHz)
with 4 way video capture , hardware compression on card and DMA to the
harddrive/s. Ideally we would use one capture card with 4 channels but they
would need to work simulataneously, not time/resource slicing/overlay.

Alternatively we would use 4 PCI Video capture cards (need PCI riser with
mini ITX board).

Any thoughts or recommended ng/discussion groups for this?

--
David Jones
Software Developer
(Embeddded Systems)
Victorian Partnership of Advanced Computing
Melbourne, Victoria Australia

 

[Paul]

Our system to be targeted for is a 4 way video capture system.
We want to simultaneously capture to disk (with hardware processing to say
MPEG 2 or 4 prior to saving to disk) 4 video inputs.
This is not a surveillance thing where 4 way PCI capture cards compose one
video stream from 4 by placing the camera contents in ¼ of the same
screen/image.

The system is meant to capture the 4 streams away from base over a long
period of time so its a performance v storage issue v power.

We could use a high performance PC with 4 PCI solots/video capture cards,
and a terrabyte or two of storage but that is not practical.

We are thinking of using a moderate capability PC (say mini ITX 1.3-1.7GHz)
with 4 way video capture , hardware compression on card and DMA to the
harddrive/s. Ideally we would use one capture card with 4 channels but they
would need to work simulataneously, not time/resource slicing/overlay.

Alternatively we would use 4 PCI Video capture cards (need PCI riser with
mini ITX board).

Any thoughts or recommended ng/discussion groups for this?

There are video capture products, that have built-in MPEG2 compression.
They are available in PCI bus and USB versions.

http://www.hauppauge.com/pages/prods_pvr.html

http://en.wikipedia.org/wiki/Mpeg
http://erg.abdn.ac.uk/research/future-net/digital-video/mpeg2.html

There is an H.264 encoder here. This one is for post-processing
an existing movie.

http://www.everythingusb.com/ads_instant_video_to-go_12252.html

Finally, found a product with H.264 involved in the actual capture.
This should do what you want, assuming the software provided with
it doesn't suck. Since the USB device does all the work, the
computer can be quite puny.

http://www.everythingusb.com/fastvdo_smartcapture_h.264_usb_encoder_13637.html

So if you buy four of these, you shouldn't have a problem with the
capture. All you need is four USB ports and a pile of cash (4 x $250).

http://www.fastvdo.com/SmartCapture/

I'm constantly amazed by the stuff you can find out there.

Paul

 

[David Jones vpac org>]

Thanks for that. Have posted query with Vendor:

Re: Smart Capture Device
Considering using 4 x of these devices in the same system simultaneously.
Want to stream 4 video cameras to (same) harddrive. (Or could have multiple
drives)
DON'T want to combine images into one (4 1/4s) as per sercurity systems.
Are there any issues with doing this.
ie Possible bottlenecks on the system side?
Does the hw stream directly to disk using DMA or is it streamed through the
CPU?

--
David Jones
Software Developer
(Embeddded Systems)
Victorian Partnership of Advanced Computing
Melbourne, Victoria Australia

 

[Paul]

Thanks for that. Have posted query with Vendor:

Re: Smart Capture Device
Considering using 4 x of these devices in the same system simultaneously.
Want to stream 4 video cameras to (same) harddrive. (Or could have multiple
drives)
DON'T want to combine images into one (4 1/4s) as per sercurity systems.
Are there any issues with doing this.
ie Possible bottlenecks on the system side?
Does the hw stream directly to disk using DMA or is it streamed through the
CPU?

The only thing that makes me a bit suspicious, is the "2GHz" processor
requirement, in their system requirements. That almost makes it seem
like the USB component has a capture device, and an H.264/AVC encoding
device as a second chip (maybe they aren't directly connected to each
other).

If the hardware had a decent design, there should really only be a
trickle of data being DMA transferred to system memory, after it
arrives via USB. I think the question I'd ask, is why it needs a 2GHz
processor, and what the real requirement is.

The ADStech Instant Video To Go used some processor, because
they needed to feed a raw stream to their USB hosted accelerator.
If the FastVDO device had a raw capture device, with a raw stream,
that should be able to be passed to the accelerator directly. It
really depends on whether the interfaces are right, for a direct
connection, as to whether that is possible or not. But even a
problem like that can be solved (there are devices with USB OTG
capability, and one of those could be used as an intermediary).

So you are right to ask some questions. If it works, it looks like
a good deal, because it doesn't use a lot of power, and if implemented
well, it shouldn't need a lot of processor. I'm amazed at times,
just how efficient these devices seem to be, compared to using
a processor to do the same job.

Paul

 

[Andy]

<http://www.adlinktech.com/PD/web/PD_detail.php?cKind=FN&pid=494&seq=&id=&sid=>
Angelo PCI-MPG24
4-CH MPEG4 Hardware Real-Time Video Compression Card