Logitech Webcam Image Acquisition using IMAQ

[Himanshu]

Hello Friends,
I have been sucessfull in acquiring continuous image using Logitech Webcam and USB port. I used the VT's that were put on the net by a few LabVIEW users. Using webcam reduces the cost of a frame grabber and expensive cameras. I have no doubt acquired the image at a low cost. Thanks to you people. Now I have to process the image and find out the following parameters from the image:
1. Dimensions of the geometric objects in the image
2.No of Objects in the image
3. No of vertices in the object
With regards to the above I would like to know a few things:
1. Since I am not using NI Cards for Image acquisition will I be able to use the IMAQ VIs for image processing?
2.How do I start the webcam image processing?
3
. Is the IMAQ toolset free of cost or it is available only after payment?
4.How do I start with webcam image processing step by step?
In short I would like to know about the webcam image processing.

[BruceAmmons]

This is where you discover the disadvantage of cheap imaging using a Webcam. The quality of the image is going to be fairly low with a lot of noise, so you may have a difficult time analyzing it unless there is a high contrast between the objects and the background. If you need calibrated measurements, that is likely to be difficult also.

It sounds like you need the NI tools for vision. They are not free, so you need to purchase them. You will also need a method of converting your image to the NI-IMAQ format. The simplest is probably 2D-array to image.

Bruce

[Irene He]

Hello,
As Bruce mentioned, the quality of image from webcam may not be good enough to analyze. Other options are you can try IEEE1394 camera or DV camcorder, they are still much cheaper than industry camera with frame grabber, but you can get much better image quality out of them. So do you just want to learn how to do image processing? I am not sure if IMAQ vision provide an evaluation version to try, if not, my tool can get you started to learn image processing. It's not free, but you can download and learn the things like thresholding the image, do color match, pattern match or blob analysis. Recently I just added the real time video stream processing functions and supporting for files format like *.mpeg, *.asf and sure *.avi, etc. I think it's fun to play with it,
you can use it for example object tracking of your camera source, etc.
my site link is:
http://www.geocities.com/irene_he/IVision.html
Irene

[Himanshu]

I am sure you all agree that Acquiring Images on LabVIEW platform is useless if the image processing can not be done. I think the quality of image can be enhanced using different colors and contrast background etc. I certainly agree that the quality is not very good but still I feel that it will serve our purpose. The main purpose of adding a camera is to get the dimensions of symmetrical geometric objects in front of camera.
Now I want to know as to how I should proceed with regards to Image processing:

1. Will the IMAQ Tools work for image that is acquired using USB port and webcam?
2. If not then what is the basic approach for processing images using USB port?
3. What is the change in image processing done on images acquired by USB and using frame grabber
?


I would like to ask you to please send me some example VI that finds out the dimensions of the object using webcam and USB port.

[Irene He]

Hi,
I'm not sure what USB driver you used to get image. If you want to use IMAQ vision for your webcam, you need to convert 2D data to IMAQ format as mentioned in previous message by Bruce. I don't have an existing vi doing the dimension thing you asked, beside this is depending on how your object looks like. Normally the method to get dimensions of an object is first getting edges(contour) of the object, then you can calculate the dimensions by doing the math.
Irene

[Vishwarath1990]

Hi Irene,

Is the link still active? I cant seem to find it.

[MangeshD]

What's your query?

[Vishwarath1990]

I wanted to know if the tools developed by Irene are stilll avialble for use

[udka]

If you have any specific question regarding acquistion with IMAQ post in new thread by giving reference to this post, it would help the forum better.
-If you are looking for NI-IMAQ for USB Cameras :http://www.ni.com/example/30030/en/