Cryptography nerd

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Joined 1 year ago
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Cake day: August 16th, 2023

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  • The Nyquist-Shannon sampling theorem isn’t subjective, it’s physics.

    Your example isn’t great because it’s about misconceptions about the eye, not about physical limits. The physical limits for transparency are real and absolute, not subjective. The eye can perceive quick flashes of objects that takes less than a thousandth of a second. The reason we rarely go above 120 Hz for monitors (other than cost) is because differences in continous movement barely can be perceived so it’s rarely worth it.

    We know where the upper limits for perception are. The difference typically lies in the encoder / decoder or physical setup, not the information a good codec is able to embedd with that bitrate.



  • Why use lossless for that when transparent lossy compression already does that with so much less bandwidth?

    Opus is indistinguishable from lossless at 192 Kbps. Lossless needs roughly 800 - 1400 Kbps. That’s a savings of between 4x - 7x with the exact same quality.

    Your wireless antenna often draws more energy in proportion to bandwidth use than the decoder chip does, so using high quality lossy even gives you better battery life, on top of also being more tolerant to radio noise (easier to add error correction) and having better latency (less time needed to send each audio packet). And you can even get better range with equivalent radio chips due to needing less bandwidth!

    You only need lossless for editing or as a source for transcoding, there’s no need for it when just listening to media










  • Opus! It’s a merge of a codec designed for speech (from Skype!) with one designed for high quality audio by Xiph (same people who made OGG/Vorbis).

    Although it needs some more work on latency, it prefers to work on bigger frames but default than Bluetooth packets likes, but I’ve seen there’s work on standardizing a version that fits Bluetooth. Google even has it implemented now on Pixel devices.

    Fully free codec!