A head in a box with BlazeFace

Yesterday I showed how to track a head using BlazeFace. Today, I show how to display the head in a square canvas. You can run it on your own head: to start a demo!

This display style doesn’t require any WebGL. I’m just using a 2D context and .drawImage.

The output from BlazeFace tends to “jitter”. The predicted face will move around with noticeable noise. To account for this, I smooth the values using exponential smoothing (the simplest smoothing function I’m aware of). This smoothing is a tradeoff; it increases smoothness but also increases latency.

What should we do when the head is partially outside the image? I choose to make the unknown region transparent. Another valid choice would be to shift the bounding box to always be inside the image, even if it doesn’t cover the head properly.

What can computers do? What are the limits of mathematics? And just how busy can a busy beaver be? This year, I’m writing Busy Beavers, a unique interactive book on computability theory. You and I will take a practical and modern approach to answering these questions — or at least learning why some questions are unanswerable!

It’s only $19, and you can get 50% off if you find the discount code ... Not quite. Hackers use the console!

After months of secret toil, I and Andrew Carr released Everyday Data Science, a unique interactive online course! You’ll make the perfect glass of lemonade using Thompson sampling. You’ll lose weight with differential equations. And you might just qualify for the Olympics with a bit of statistics!

It’s $29, but you can get 50% off if you find the discount code ... Not quite. Hackers use the console!

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