alt Hacker NewsOnce you start looking at the world through the lens of frequency domain a lot of neat tricks become simple. I have some demo code that uses fourier transform on webcam video to read a heartrate off a person's face, basically looking for what frequency holds peak energy.
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cogman10 • last Thursday at 10:47 PM
It's effectively the underpinning of all modern lossy compression algorithms. The DCT which underlies codecs like Jpeg, h264, mp3, is really just a modified FFT.
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isolli • yesterday at 10:45 AM
There is also a loose analogy with finance: act (trade) when prices cross a certain threshold, not after a specific time.
Chrupiter • last Thursday at 11:31 PM
I don't think pulsing skin (due to blood flow) is visible from a webcam though.
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>Once you start looking at the world through the lens of frequency domain a lot of neat tricks become simple.
Not the first time I've heard this on HN. I remember a user commenting once that it was one of the few perspective shifts in his life that completely turned things upside down professionally.