FLAC 1.3.4 - Hackdot

Re:FLAC 1.3.4 by dale_glass on Wednesday February 23, 2022 @04:46AM (#30439437)

Well, I say "black magic" because at least to me it's a quite mysterious creation. But I'm no audio engineer.

It's a lossy codec that's for some reason fixed rate, and shrinks audio by exactly 1/4th. The resulting quality is very good (works perfectly fine for music), and it's much faster than Opus. It retains stereo and high frequencies and sounds just fine. I'm sure there's a tradeoff somewhere, but it's certainly good enough to hold music events without people complaining.

I think it might be possibly related to codecs like AptX.

So far I've not found anything competitive that we could use -- stuff is either closed, or far more CPU intensive.

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Re:FLAC 1.3.4 by astrange on Wednesday February 23, 2022 @05:00AM (#30439526)

Yeah, it sounds like ADPCM with a fixed ratio like that. It's extremely simple and adds no latency, which are both good for streaming.

Usually a fixed compression ratio is a terrible tradeoff, but for streaming it kind-of makes sense.

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Re:FLAC 1.3.4 by dale_glass on Wednesday February 23, 2022 @06:39AM (#30440035)

I don't think it's ADPCM since it sounds really good. I'm not an audiophile or have done any comprehensive testing, but it' the kind of quality a normal person would use for music without complaining.

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Re:FLAC 1.3.4 by astrange on Wednesday February 23, 2022 @07:14PM (#30448604)

That was meant to agree with you - AptX is a kind of ADPCM with some other filters added on, so this could be the same thing. That's how it gets low latency.

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