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TSAC: Low Bitrate Audio Compression

bellard.org

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Re: TSAC: Low Bitrate Audio Compression

#31

Post by Max-q »

shvedsky wrote: post #28
kazinator wrote: post #25

This doesn't have much of a use case. - Can't use it in telephony (obvious application for low bitrates); phone handsets and headsets don't have the power to do it in real time. - Very small files of good quality would be useful in tiny embedded systems that have low flash space: but what systems of that type have the processing power for decoding? Very low storage more or less goes hand in hand with weak processing.…

don't be such a debbie downer! celebrate it, and we'll find a use for that some day

Innovation goes in steps and iterations ;) When mp3 came out, I could just barely play a song encoded from 44.1kHz/16 bit stereo on my PC, taking almost 100% CPU. Today they can be played on a cheap microcontroller.

I like that they share their work, it can lead to something some day.

Re: TSAC: Low Bitrate Audio Compression

#32

Post by unwind »

userbinator wrote: post #7

Clicked the download link wanting to take a look at the source... and was a bit perplexed before quickly canceling it. 237MB, compressed , for an audio codec!? At that point one can't help but think that the samples are already in the decoder itself. I wonder how it compares to https://en.wikipedia.org/wiki/Codec2 and related codecs, which go even lower for bitrate.

That sounded interesting, so I did the download and had a look in the archive. Here's the list of contents:

    $ tar tvzf ~/Downloads/tsac-2024-04-08.tar.gz 
    drwxrwxr-x bellard/bellard   0 2024-04-08 14:47 tsac-2024-04-08/
    -rw-rw-r-- bellard/bellard 3040 2024-04-08 14:47 tsac-2024-04-08/readme.txt
    -rwxrwxr-x bellard/bellard 3979504 2024-04-08 14:47 tsac-2024-04-08/libnc_cuda.so
    -rwxrwxr-x bellard/bellard  565336 2024-04-08 14:47 tsac-2024-04-08/libnc.so
    -rw-rw-r-- bellard/bellard 49639706 2024-04-08 14:47 tsac-2024-04-08/tsac_stereo_q8.bin
    -rw-rw-r-- bellard/bellard 85407494 2024-04-08 14:47 tsac-2024-04-08/dac_stereo_q8.bin
    -rw-rw-r-- bellard/bellard 49633561 2024-04-08 14:47 tsac-2024-04-08/tsac_mono_q8.bin
    -rw-rw-r-- bellard/bellard       31 2024-04-08 14:47 tsac-2024-04-08/Changelog
    -rwxrwxr-x bellard/bellard   287536 2024-04-08 14:47 tsac-2024-04-08/tsac
    -rw-rw-r-- bellard/bellard 85143422 2024-04-08 14:47 tsac-2024-04-08/dac_mono_q8.bin
So yeah, it's not exactly a compact stand-alone implementation, but on the other hand it does advanced GPU stuff so I guess nobody expected it to ... or perhaps I did, just a little, based on the author's reputation. :)

Re: TSAC: Low Bitrate Audio Compression

#33

Post by briansm »

Reminds me of the old IBM 'RECOVC' codec from around 2000 where they compressed Mel-bank speech.

https://ieeexplore.ieee.org/document/7075313

All the patents around that are long-dead so good time to do an updated version I guess.

If you wanted to do something similar but with way lower bitrates (e.g. 300bps), then look at the NRV codec:

https://www.researchgate.net/publication/224209493_300_bps_n...

Re: TSAC: Low Bitrate Audio Compression

#34

Post by ant6n »

kazinator wrote: post #25

This doesn't have much of a use case. - Can't use it in telephony (obvious application for low bitrates); phone handsets and headsets don't have the power to do it in real time. - Very small files of good quality would be useful in tiny embedded systems that have low flash space: but what systems of that type have the processing power for decoding? Very low storage more or less goes hand in hand with weak processing.…

I think the big use case is satellite telephony and satellite radio/audio/podcast play. You could do all audio applications off a 3KBit/s connection - that’s completely insane.

It would probably have to be optimized a bit further though, both in terms of computing as well as size. Goal would probably be real time encoding on an iPhone SE without breaking too much of a sweat, and a encoder/decoder perhaps less than 200MB?

I am curious how well this does work with a full orchestra music — that’s where encoders usually croak. Give me a sample of the Star Wars theme.

Re: TSAC: Low Bitrate Audio Compression

#35

Post by kazinator »

Max-q wrote: post #31
shvedsky wrote: post #28

Earlier quoted context omitted.

don't be such a debbie downer! celebrate it, and we'll find a use for that some day

Innovation goes in steps and iterations ;) When mp3 came out, I could just barely play a song encoded from 44.1kHz/16 bit stereo on my PC, taking almost 100% CPU. Today they can be played on a cheap microcontroller. I like that they share their work, it can lead to something some day.

MP3's were playable on cheap boom box stereos, and portable CD players, 20+ years ago. Such consumer devices capable of decoding MP3's appeared within less than half a decade of MP3 itself, by my recollection.

Re: TSAC: Low Bitrate Audio Compression

#36

Post by jjcm »

adamzochowski wrote: post #22
jjcm wrote: post #13

Always love a good bellard ship. This is definitely better than some of the others out there. I threw together some comparisons here at 7kb/s for mp3/opus/aac: https://non.io/TSAC-Comparisons Happy to add other comparisons if others want any. Overall, it's FAR better at these lower bit rates, but that doesn't mean it's necessarily good. One issue I see off the bat is that volume is fairly inconsistent in the output f…

Since Ballard's codec is "AI" based, can you add google's lyrav2 ( https://github.com/google/lyra ) and Facebook's/meta EnCodec ( https://github.com/facebookresearch/encodec ). Also I don't seem to be able to access your page, so there might be error. Finally, when doing opus comparison it's good now to denote if it is using Lace or NoLace decoder post processing filters that became available in opus 1.5 (note, this…

> Also I don't seem to be able to access your page, so there might be error.

Interesting, do you have javascript turned off? Can you access this page? https://html.non.io/TSAC-Comparisons/

Re: TSAC: Low Bitrate Audio Compression

#37

Post by kazinator »

ant6n wrote: post #34
kazinator wrote: post #25

This doesn't have much of a use case. - Can't use it in telephony (obvious application for low bitrates); phone handsets and headsets don't have the power to do it in real time. - Very small files of good quality would be useful in tiny embedded systems that have low flash space: but what systems of that type have the processing power for decoding? Very low storage more or less goes hand in hand with weak processing.…

I think the big use case is satellite telephony and satellite radio/audio/podcast play. You could do all audio applications off a 3KBit/s connection - that’s completely insane. It would probably have to be optimized a bit further though, both in terms of computing as well as size. Goal would probably be real time encoding on an iPhone SE without breaking too much of a sweat, and a encoder/decoder perhaps less than 20…

How does satellite telephony work? Alice calls Bob over satellite. Alice's telephone is on AC power, and contains a GPU cluster, and Bob's is the same?

Re: TSAC: Low Bitrate Audio Compression

#38

Post by Agingcoder »

kazinator wrote: post #25

This doesn't have much of a use case. - Can't use it in telephony (obvious application for low bitrates); phone handsets and headsets don't have the power to do it in real time. - Very small files of good quality would be useful in tiny embedded systems that have low flash space: but what systems of that type have the processing power for decoding? Very low storage more or less goes hand in hand with weak processing.…

Storage of large amounts of voice conversations for regulatory purposes ? ( say, a trading floor )

Re: TSAC: Low Bitrate Audio Compression

#39

Post by anthk »

ant6n wrote: post #34
kazinator wrote: post #25

This doesn't have much of a use case. - Can't use it in telephony (obvious application for low bitrates); phone handsets and headsets don't have the power to do it in real time. - Very small files of good quality would be useful in tiny embedded systems that have low flash space: but what systems of that type have the processing power for decoding? Very low storage more or less goes hand in hand with weak processing.…

I think the big use case is satellite telephony and satellite radio/audio/podcast play. You could do all audio applications off a 3KBit/s connection - that’s completely insane. It would probably have to be optimized a bit further though, both in terms of computing as well as size. Goal would probably be real time encoding on an iPhone SE without breaking too much of a sweat, and a encoder/decoder perhaps less than 20…

I remember playing OPUS files at 16 KBPS over a... 2G? connection with mplayer's caching options. The audio sounded a bit better than MP3@32 or Real Audio back in the day.

As the music was "avant gardé", it almost fitted the genre.

Re: TSAC: Low Bitrate Audio Compression

#40

Post by orlp »

Agingcoder wrote: post #38
kazinator wrote: post #25

This doesn't have much of a use case. - Can't use it in telephony (obvious application for low bitrates); phone handsets and headsets don't have the power to do it in real time. - Very small files of good quality would be useful in tiny embedded systems that have low flash space: but what systems of that type have the processing power for decoding? Very low storage more or less goes hand in hand with weak processing.…

Storage of large amounts of voice conversations for regulatory purposes ? ( say, a trading floor )

Or mass surveillance.
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