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How to Turn Music Into Colors With a Wi-Fi Bridge

The ESP8266 microchip is an unexpected powerhouse

4 min read
Photo of saxophone
Photo: Charles Lohr

Several years ago, I wrote an algorithm I called ColorChord, which assigned colors to notes. The neat thing about it was that every time I played a note, the same color was assigned—regardless of the octave. By using these color values to control LEDs, I had a whole new way to visualize chords and melodies. Sadly, the algorithm was a bit clunky. The Pentium-based processors available at the time had difficulty running the algorithm in real time, forcing me to use specialized graphics processors.

Fast-forward a couple of years: A friend of mine dug into the algorithm and found it could be sped up enormously. Based on his feedback, I rewrote it twice. Eventually, it could easily run on a desktop CPU, and further tweaks and changes made it possible to run on a 168-megahertz STM32F407/417 microcontroller. Eventually, I wondered if I could run it on something even simpler—something as simple as a Wi-Fi bridge?

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From WinZips to Cat GIFs, Jacob Ziv’s Algorithms Have Powered Decades of Compression

The lossless-compression pioneer received the 2021 IEEE Medal of Honor

11 min read
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Photo of Jacob Ziv
Photo: Rami Shlush
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Lossless data compression seems a bit like a magic trick. Its cousin, lossy compression, is easier to comprehend. Lossy algorithms are used to get music into the popular MP3 format and turn a digital image into a standard JPEG file. They do this by selectively removing bits, taking what scientists know about the way we see and hear to determine which bits we'd least miss. But no one can make the case that the resulting file is a perfect replica of the original.

Not so with lossless data compression. Bits do disappear, making the data file dramatically smaller and thus easier to store and transmit. The important difference is that the bits reappear on command. It's as if the bits are rabbits in a magician's act, disappearing and then reappearing from inside a hat at the wave of a wand.

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