alt Hacker NewsFun fact about laser discs. They are analogue not digital. CD’s store digital information with the presence or absence of pits. Fairly ancient but still fundamentally feels like a very old version of a thumb drive.
Laser discs are not digital. They encode the analogue video signal’s value as the length of the pit. It is digitized in the time domain - sampled at some frequency, but the “vertical” signal value is stored entirely analogue. In terms of encoding it’s more similar to a VHS tape than a CD. Kinda crazy.
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yeah i remember learning this as a kid and being surprised. i originally thought laserdiscs were modern high tech, but then they turned out to actually be from the late 70s/early 80s with the primitive analog video encoding where red book audio cds of the mid to late 80s were actually digital.
So how does writes work? Does an analog signal translate into pit-lengths with absolute precision?
Everything is analog when it gets to real world
> Laser discs are not digital... It is digitized in the time domain
Laser disks are 100% digital (as you said, they store digits in the time domain).
They don't encode their data using binary like a CD does.
"Binary" and "digital" are two separate and unrelated concepts.