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Codec2: A Whole Podcast on a Floppy Disk

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Re: Codec2: A Whole Podcast on a Floppy Disk

#81

Post by carapace »

jancsika wrote: post #44

Would be a fun experiment to use something like 3 or even 1 sine to get unintelligible speech, but then pair it with subtitles where each syllable of the text is animated synchronized with the speech. (Like the "follow the bouncing ball" song lyric animations.) By pairing the audio with the text, you would almost certainly convince the listener that they can understand it. Edit: typo

;-)

Sine-Wave Speech Demonstration https://youtu.be/EWzt1bI8AZ0?t=74

> Sine-wave speech is an intelligible synthetic acoustic signal composed of three or four time-varying sinusoids. Together, these few sinusoids replicate the estimated frequency and amplitude pattern of the resonance peaks of a natural utterance (Remez et al., 1981). The intelligibility of sine-wave speech, stripped of the acoustic constituents of natural speech, cannot depend on simple recognition of familiar momentary acoustic correlates of phonemes. In consequence, proof of the intelligibility of such signals refutes many descriptions of speech perception that feature canonical acoustic cues to phonemes. The perception of the linguistic properties of sine-wave speech is said to depend instead on sensitivity to acoustic modulation independent of the elements composing the signal and their specific auditory effects.

~ http://www.scholarpedia.org/article/Sine-wave_speech

Re: Codec2: A Whole Podcast on a Floppy Disk

#82

Post by particleman2 »

triangleman wrote: post #78
gwern wrote: post #66

Earlier quoted context omitted.

Codec2 might be patent-free, but Codec2 with a WaveNet decoder isn't because WaveNet (convolutional neural networks for generating audio sequence data) is patented: https://patents.justia.com/patent/20180075343

raises hand Question for IP experts: now that I have heard of the existence of WaveNet and a rough idea of how it works (training a neural network to decode low-bitrate speech data with as much fidelity as possible to the original), would I be prohibited from selling a similar product built with the same technique? How about if I had never heard of WaveNet and went about doing the same thing?

Why do you hate me?

Re: Codec2: A Whole Podcast on a Floppy Disk

#83

Post by matt4077 »

triangleman wrote: post #78
gwern wrote: post #66

Earlier quoted context omitted.

Codec2 might be patent-free, but Codec2 with a WaveNet decoder isn't because WaveNet (convolutional neural networks for generating audio sequence data) is patented: https://patents.justia.com/patent/20180075343

raises hand Question for IP experts: now that I have heard of the existence of WaveNet and a rough idea of how it works (training a neural network to decode low-bitrate speech data with as much fidelity as possible to the original), would I be prohibited from selling a similar product built with the same technique? How about if I had never heard of WaveNet and went about doing the same thing?

Yes, independent implementations of patented works are covered by the patent.

BUT: patents are far more specific than just "a neural network to decode low-bitrate speech data with as much fidelity as possible to the original)". Starting with that goal, you are unlikely to recreate WaveNet's specific structure that is patented.

In fact, WaveNet describes a more general method to efficiently work with sound signals, somewhat comparable to convolutions for images. It's also not impossible to work with sound using alternative MM structures that are not patented, and might actually perform better than WaveNet.

Re: Codec2: A Whole Podcast on a Floppy Disk

#84

Post by [deleted] »

jancsika wrote: post #44

Would be a fun experiment to use something like 3 or even 1 sine to get unintelligible speech, but then pair it with subtitles where each syllable of the text is animated synchronized with the speech. (Like the "follow the bouncing ball" song lyric animations.) By pairing the audio with the text, you would almost certainly convince the listener that they can understand it. Edit: typo

[deleted]

Re: Codec2: A Whole Podcast on a Floppy Disk

#85

Post by mr_donk »

This is amazing! With this codec and enough processing power, you could do this bidirectionally and have enough bandwidth to stream a two way realtime voice chat using 2400bps modems over a standard analog phone line!!! ... Oh... Wait a minute...

Re: Codec2: A Whole Podcast on a Floppy Disk

#87

Post by baobrien »

hatsunearu wrote: post #86

Side note: I'm still waiting for an open source, cheap way to do FreeDV/Codec2 on VHF either with a dongle that goes between a raspi/SBC or a laptop and a cheap ass radio like a baofeng, or an inexpensive radio with Codec2 support.

I think 2400B support is coming to the FreeDV GUI soon. I've seen some work done on that. That'll let you use a cheap FM radio and a laptop to get on the air with something codec2 based. I'm slowly chipping away at a TDMA mode for SDRs, but that's still probably a ways off.

Re: Codec2: A Whole Podcast on a Floppy Disk

#88

Post by akvadrako »

mrob wrote: post #33
corruptio wrote: post #9

Having grown accustom to MP3 artifacts, it's strange to hear artifacts that are natural, but just aren't quite right. More specifically, in the male voice sample: "sold about seventy-seven", I received it as "sold about se th enty-seven".

If we're abandoning accurate reproduction of sound and just making up anything that sounds plausible, there's already a far more efficient codec: plain text. Assuming 150wpm and an average 2 bytes per word (with lossless compression), we get about 5bps, which makes 2400bps look much less impressive. Add some markup for prosody and it will still be much lower. This codec also has the great advantage that you can turn…

What you might be able to do is your the text codec as the first pass, then augment the audio with Codec2 or so to capture the extra information (inflections, accent, etc...), for something in between 2 and 700bps.

Re: Codec2: A Whole Podcast on a Floppy Disk

#89

Post by c3534l »

triangleman wrote: post #78
gwern wrote: post #66

Earlier quoted context omitted.

Codec2 might be patent-free, but Codec2 with a WaveNet decoder isn't because WaveNet (convolutional neural networks for generating audio sequence data) is patented: https://patents.justia.com/patent/20180075343

raises hand Question for IP experts: now that I have heard of the existence of WaveNet and a rough idea of how it works (training a neural network to decode low-bitrate speech data with as much fidelity as possible to the original), would I be prohibited from selling a similar product built with the same technique? How about if I had never heard of WaveNet and went about doing the same thing?

WaveNet is actually a bit more complicated than that. But its still probably recreatable if you read the paper.

Re: Codec2: A Whole Podcast on a Floppy Disk

#90

Post by c3534l »

raphlinus wrote: post #24
jakobegger wrote: post #22

Earlier quoted context omitted.

Yes, and "certificates" sounds like "certiticates". Reminds me of a story about a copying machine that had a image compression algorithm for scans which changed some numbers on the scanned page to make the compressed image smaller. (Can't remember where I read about that, must have been a couple years ago on HN)

It's the lossy jbig2 compression in Xerox copiers: http://www.dkriesel.com/en/blog/2013/0802_xerox-workcentres_... And yes, I think this is a relevant comparison. As the entropy model becomes more sophisticated, errors are more likely to be plausible texts with different meaning, and less likely to be degraded in ways that human processing can intuitively detect and compensate for.

This is a big rabbit hole of issues I'd never even considered before. Should we be striving to hide our mistakes by making our best guess, or make a guess, that if wrong, is easy to detect?
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