This past semester I took a course in Computer Vision. The course culminated in a final project of our choosing, so I worked with my classmates, Luke Gessler and Minh Nguyen, to create a person-tracker using the Histogram of Oriented Gradients (HOG) descriptor.
In a nutshell, image descriptors are useful ways to compress an image into its most meaningful parts (its "features"), which usually takes the form of a vector. The HOG descriptor is a specific type of image descriptor that works very well for succinctly describing the shape of humans. This blog post has a good description of how the HOG descriptor works.
Here's an example output video from our code:
For more in-depth information about what we did, check out:
Our final write-up
Slides from our presentation
Our code repo