Kinect's AI Breakthrough Explained 97
mikejuk writes "Microsoft Research has just published a scientific paper (PDF) and a video showing how the Kinect body tracking algorithm works — it's almost as impressive as some of the uses the Kinect has been put to. This article summarizes how Kinect does it. Quoting: '... What the team did next was to train a type of classifier called a decision forest, i.e. a collection of decision trees. Each tree was trained on a set of features on depth images that were pre-labeled with the target body parts. That is, the decision trees were modified until they gave the correct classification for a particular body part across the test set of images. Training just three trees using 1 million test images took about a day using a 1000-core cluster.'"
Re:Sounds like vision, all right (Score:5, Insightful)
Random forests have always been a nice classifier to use when working with really wacky data types. This is due in part to how easy it is to customize them; a lot of the ways they can be tweaked and tuned and customized have fairly intuitive effects on the outcome and behavior of the classifier. In my experience, while neural nets can also be pretty powerful, they are often much harder to work with as the parameters you have for tweaking can be really non-intuitive. We sometimes joke about neural nets being "black magic" because the training and tweaking can be really uninterpretable.
However, the biggest reason random forests were used is probably because they are extremely fast on current chips, probably a couple orders of magnitude faster than neural nets when the trees are hard coded.
Re:"Almost as impressive"? (Score:2, Insightful)
Hum, no, actually, they just used a known for years technic of machine learning on a huge sample of data and it worked pretty well.
From my point of view, there is no major breakthrough but still it's a nice solution.
Re:More advertising masquerading as news (Score:4, Insightful)
And no doubt backed up by a dozen patents.
Of course. That's the purpose of patents, to encourage inventors to publish their inventions openly.