07-05-2011 07:45 AM
Hi,
I was having a read through the NI IMAQ Vision Concepts manual, looking for fast reliable methods to use for object tracking. I looked through edge detection, pattern matching and cross-correlation. None of these really seem suited for what I need. Edge detection is unreliable when a lot of noise is present. Pattern matching means I can't run object tracking in real-time especially if I don't know what object to look for until Ive seen the images first, hence not being able to set a template. And cross-correlation seems to be too PC intensive to run smoothly enough. Does anyone have any suggestions for alternative object tracking techniques?
Currently I'm just using 'IMAQ Count Objects 2' which is doing some straightforward thresholding to separate the objects I want from the background which is good enough so far for relatively clean images, but I'll want to be using it for much noiser images. Im also interested in extrapolating the change in distance (offset) between each image by judging how far object(s) have moved in successive images.
07-05-2011 08:07 AM
This is very dependant on what you are tracking and what the background is.
The simplist case is a simple binary threshold on a color or intenisty or HSL. then a blob analysis to filter out wrong sized blobs and keep the correct size blob.
maybe some sample images and backgrounds would help suggestions.
07-05-2011 09:13 AM
Well I'm already sort of doing binary thresholding, It works fine so far, but the issue is more about flexibility if it could work on a lot of different images which isn't the case. I can provide sample images but I will want to be looking at a huge variety of sample images so I don't know how helpful it would be to show a few since other images could be hugely different from the sample ones. The images are from an Atomic Force Microscope, it produces a topography of the sample surface you wish to scan, may be a biological sample (DNA/Chromosomes/Collagen/Enamel), or a chemical compound or silicon/graphene, so Im not looking at any one particular set of images, more interested in a robust solution for any and all images. The objects that appear in the image may be circular in some cases, or elliptical, irregular, lines, e.t.c.
07-07-2011 05:30 AM
bump