CREU Project Blog


Blob Detection Demo
May 16, 2008, 3:50 pm
Filed under: Uncategorized

This is one of the earlier demo we wrote to experiment with blob detection.  The program uses the camera on the macbook or the Logitech webcam to capture images and track color blobs specified by the user.  After the program started, user can click on the color they want to track in the application window and the program will track blobs of that color and calculate the size of the blobs.

Blob tracking might at first seems like a trivial task; it was a lot more difficult than we previously anticipated.  The program picks up noises from the environment and it returns irrelevant blobs from time to time.  We try to overcome this by smoothing and performing segmentation on the image prior to searching for the color blobs.  The program is still prone to error if the color is too similar to the background color, the blob is too small or the lighting condition changes.  The source code can be downloaded here .  (Note: wordpress doesn’t allow user to upload zip file, so I renamed it to BlobDetectionDemo.pdf.  To decompress the source code, you have to change the file name to BlobDetectionDemo.zip.)

 

Figure 1. A screen shot of the program tracking a color finger wrap.  It puts a red box around of finger wrap and provide a label indicating its size.

Figure 2. We find that the size label increases quadratically as we move the finger closer to the camera.

 



Meetings of the Mind
May 16, 2008, 3:50 pm
Filed under: Uncategorized

We presented our project’s poster at the meetings of the mind hosted by Carnegie Mellon University’s Undergraduate Research Organization.  Here is the pdf for the poster.  

 



Mid Year Report
January 5, 2008, 4:41 am
Filed under: Uncategorized
Current Progress:

Synopsis: We are currently working on a multi-touch solution using a webcam to track color bands on a finger.  We are only able to track one color at the moment, but the program will soon be able to track multiple color.   

Method:  
1) We use the quick time java library to capture video contents from the webcam/iSight.  
2) We use a statistical regional matching algorithm (see reference) to segment the video frames into statistically important regions.  By employing this extra step we are able to reduce the amount of noise.
3) We use a color tracking algorithm to find the object of importance

Here is a demo video of color tracking program.  The window on top left is the post processed image after running the video through the statistical region matching algorithm.
 
Reference: R. Nock, F. Nielsen: Statistical Region Merging. IEEE Trans. Pattern Anal. Mach. Intell. 26(11): 1452-1458 (2004)