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cathair28

Help with using an analog video signal to process frames

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I recently had a project dropped into my lap and have had a tough time finding information about it on the web.  Here is a quick outline of my current issue.

 

I am trying to take in an analog video signal (640x480) and process the stream in LabVIEW/IMAQ/IMAQdx (end goal would be to have uncompressed video being processed).  I need to be able to have an uncompressed image to do calculations on. I am currently trying to achieve this by using an axis video server and converting the analog signal into a digital signal and finding the camera via an IP address (having networked video was requested as well...   :frusty:  Not a must though).

 

My understanding is that LabVIEW takes in the video stream as mjpeg (please correct me if I am wrong) and even at the lowest compression setting mjpeg streams are still compressed pretty heavily and use a lossy compression algorithm (again correct me if I am wrong) which will make doing any reliable image processing for me very difficult.

 

So my question is... Is there a better way to do this using any other hardware?  We will be putting the software on a pc like this, so I am unable to use pci/pci-e boards/cards but something through USB or Ethernet ports is fair game.

 

I really appreciate any help I can get!   :unsure:

 

 

I am using LabVIEW 2011 with Vision 2011

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I recently had a project dropped into my lap and have had a tough time finding information about it on the web.  Here is a quick outline of my current issue.

 

I am trying to take in an analog video signal (640x480) and process the stream in LabVIEW/IMAQ/IMAQdx (end goal would be to have uncompressed video being processed).  I need to be able to have an uncompressed image to do calculations on. I am currently trying to achieve this by using an axis video server and converting the analog signal into a digital signal and finding the camera via an IP address (having networked video was requested as well...   :frusty:  Not a must though).

 

My understanding is that LabVIEW takes in the video stream as mjpeg (please correct me if I am wrong) and even at the lowest compression setting mjpeg streams are still compressed pretty heavily and use a lossy compression algorithm (again correct me if I am wrong) which will make doing any reliable image processing for me very difficult.

 

So my question is... Is there a better way to do this using any other hardware?  We will be putting the software on a pc like this, so I am unable to use pci/pci-e boards/cards but something through USB or Ethernet ports is fair game.

 

I really appreciate any help I can get!   :unsure:

 

 

I am using LabVIEW 2011 with Vision 2011

 

I think you are after an analogue frame grabber rather than a trans-coder..

Something more akin to the boxed version of the VRmagic AVC-2 (I've never used it, but give it as an example)

Edited by ShaunR
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I think you are after an analogue frame grabber rather than a trans-coder..

Something more akin to the boxed version of the VRmagic AVC-2 (I've never used it, but give it as an example)

 

Thanks for the response, I have been running some tests with my current setup (the axis video encoder) and the loss of image quality via compression may not be as bad as I had thought.  That being said, it will take a fair bit more testing before I will feel confident about that.  

 

Based on your suggestion I believe I may pick up one of these and run some comparisons.  There is still a desire for the video to be put on a network so I am still open to suggestions for how to accomplish that task. 

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Thanks for the response, I have been running some tests with my current setup (the axis video encoder) and the loss of image quality via compression may not be as bad as I had thought.  That being said, it will take a fair bit more testing before I will feel confident about that.  

 

Based on your suggestion I believe I may pick up one of these and run some comparisons.  There is still a desire for the video to be put on a network so I am still open to suggestions for how to accomplish that task. 

 

Can't your PC box do it?  You are plugging it in via USB, so making it available over TCPIP should be straight forward since it has Gigabit LAN and WiFi.

 

Another alternative is Raspberry PI, but now we don't need your box or LabVIEW!

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What you're looking for is an analog frame grabber that supports DirectShow (which works out of the box with NI IMAQ like any webcam) or otherwise provides an API thats easy enough to integrate into LabVIEW.  

 

We've had good luck with ImperX and their analog frame grabbers designed for laptops.  They have DirectShow drivers and their own API which gives some additional control over acquisition (and a LabVIEW driver).  It doesn't look like your PC supports a Cardbus card, so thats probably out of the question.  

 

There are a number of inexpensive analog USB frame grabbers which might suit your needs.  We've tried some of them and have found all of them to have some quirks (nothing serious).  Most of these are pretty cheap, so you might as well try a few.  Since these will all appear like a webcam, they'll directly work with IMAQ... so write the code once, try them all.

 

We've been looking at another product from Pleora, but they have an analog frame grabber that works over GigE

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What you're looking for is an analog frame grabber that supports DirectShow (which works out of the box with NI IMAQ like any webcam) or otherwise provides an API thats easy enough to integrate into LabVIEW.  

 

We've had good luck with ImperX and their analog frame grabbers designed for laptops.  They have DirectShow drivers and their own API which gives some additional control over acquisition (and a LabVIEW driver).  It doesn't look like your PC supports a Cardbus card, so thats probably out of the question.  

 

There are a number of inexpensive analog USB frame grabbers which might suit your needs.  We've tried some of them and have found all of them to have some quirks (nothing serious).  Most of these are pretty cheap, so you might as well try a few.  Since these will all appear like a webcam, they'll directly work with IMAQ... so write the code once, try them all.

 

We've been looking at another product from Pleora, but they have an analog frame grabber that works over GigE

 

Thanks for the response, I think ill do as you suggested and try a few different ones

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