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   iced depresso (icedquinn@blob.cat)'s status on Saturday, 02-Mar-2024 02:06:56 JST iced depresso
   from what i recall most of freearc's big chungus savings is because of the srep filter. it had a custom lzw called tornado but the 'next' version is just using zstd.
   
   the srep filter is just like.. does a very long range block deduplication or something.
   
   dwarfs does a different odd thing where it turns files in to blocks and then it does another thing where it sorts blocks by hamming distance or something. basically runs everything through similarity hashes and stores things clustered that way so the zstd pass can better exploit it.
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     iced depresso (icedquinn@blob.cat)'s status on Saturday, 02-Mar-2024 02:20:39 JST iced depresso

     in reply to

     • picofarad
     @picofarad i saw fabrice had a neural compressor thingy but i haven't paid much attention to them.
     
     google uses one for phone compression; they have some wavenet to wavenet thing that has a neural compressor output tokens they send over the wire. i think that was remade as LPCNet by xiph, but hasn't gotten much love.
     
     lpcnet does the same over codec2, with the vocoder layers there to reconstruct voice quality that codec2 utterly massacres
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     picofarad (picofarad@noauthority.social)'s status on Saturday, 02-Mar-2024 02:20:40 JST picofarad

     in reply to

     @icedquinn for the last 20 years it's bugged me that there's no real multi-pass compression solution; however there's headway made with ML compression, zip does 1gb wiki dump @ 300MB and current SOTA is 112MB using "AI" whatevers.

     If i had to store stuff on tape, say, i'd dedupe and try to force the "already compressed" stuff to the end of the archive. then i'd have to start googling what the SOTA is. I'd also parchive onto a blu-ray just in case.

     the wiki thing is allowed 50 hours to unzip!

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     iced depresso (icedquinn@blob.cat)'s status on Saturday, 02-Mar-2024 02:35:30 JST iced depresso

     in reply to

     • picofarad
     @picofarad i've mostly used opus but its not small enough to fit in that small of a band.
     
     codec2 is probably the best open one if you need to cram in to a tiny space.
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     picofarad (picofarad@noauthority.social)'s status on Saturday, 02-Mar-2024 02:35:31 JST picofarad

     in reply to

     @icedquinn slightly off-topic, what's the best voice codec? how many khz / kbit/s? One of these days i'm going to implement something to sound like AM on sideband on HF radio which is ~2.5khz wide