The October 2022 issue of IEEE Spectrum is here!

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iCandy: A Better View

A panoramic vision system, an eye tracker, and a 3-D model of a fetus

1 min read
iCandy: A Better View

Photo: Osservatore Romano/Reuters
Who says the church is behind the times? Pope Benedict XVI is shown here using an iPad to post a tweet on 12 December. By the time the octogenarian—whose Twitter handle is @pontifex—sent his first 140-character message, he’d already gained more than a million followers.

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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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