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> 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.

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Um... I think they store "PCM encoded-ish" but the length of the pits are not discrete on / off like on a CD but various arbitrary lengths, so analog.

The sound was also analog to begin with, then the same encoding as CDs, then after that AC-3 and DTS.


"Digital" means you represent information using digits. Discrete numbers. "on/off" is binary. "Analog" means not using digits but instead an alternative (analogous) representation of the original data, usually continuous.

The grooves in a vinyl LP directly represent (are analogous to) the variations in sound pressure interpreted by our ears as sound. The grooves are continuously varying in direct proportion to the continuously varying sound waves. That's analog.

Converting analog video signals into a sequence of integral digits (even if it's pulsed-code modulation) is an analog-to-digital conversion, and storing those digits on a medium makes that a digital medium. It may just not be a binary digital medium.




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