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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

#61

Post by gsich »

IshKebab wrote: post #20
Ambroos wrote: post #12

That is very impressive! I wonder if a WaveNet decoder could be built for phone calls, as those still sound awful. If it's possible to do this only on the decoder side you don't have to wait for your network to start supporting HD voice or VoLTE to get better quality audio!

Actually if you're lucky and make a phone call with HDVoice, or whatever they're calling it, the quality is excellent. It makes a huge difference. Unfortunately the place where you really want good quality is call centres - it's often hard to hear people and half of the reason is the shitty POTS quality - and call centres will probably get HDVoice in about 40-50 years. Maybe. Edit: nm should have read all of your com…

What do you mean with "HDVoice"? On landline connections this usually means G722. G711u/a is definitly not "HD".

Re: Codec2: A Whole Podcast on a Floppy Disk

#62

Post by gsich »

namibj wrote: post #59
reaperducer wrote: post #34

Earlier quoted context omitted.

>Actually if you're lucky and make a phone call with HDVoice, or whatever they're calling it, the quality is excellent Can confirm. I spend a lot of time in fringe reception areas, but every now and then I get a good, strong signal and the HD Voice kicks in between my iPhone and my wife's and it sounds like she's standing right next to me. It really is something to experience, especially if the previous phone call wa…

Also why no one really appreciated ISDN over here in central Europe. Yes, there are ways to do better _now_, and it would have been trivial to support channels with better codecs by negotiating something different than u-law 8kHz PCM, but back then that resulted in rather good quality. The issue was that few people got ISDN phones, which resulted in them using analog outputs on an adapter device, which got later inco…

>Also why no one really appreciated ISDN over here in central Europe.

Except Germany. Which had probably the best telephone system in the world when they deployed ISDN nationwide.

Re: Codec2: A Whole Podcast on a Floppy Disk

#63

Post by sbr464 »

calabin wrote: post #46
sbr464 wrote: post #31

I've become almost entranced with the concept of comparing things to the size of a Floppy Disk. I'm actually planning to get a tattoo of one on my right forearm. I've been working on a large business management platform for the last couple of years and noticed that after investing $500k (salaries/etc) and building a huge amount of functionality, the frontend and backend codebases are still under 1.5mb. Pretty amazing…

I actually got a floppy disk tattoo on my foot in a moment of spontaneity (bottomless mimosas). https://imgur.com/a/slCG519

nice haha

Re: Codec2: A Whole Podcast on a Floppy Disk

#64

Post by gwern »

skykooler wrote: post #48
Ambroos wrote: post #12

That is very impressive! I wonder if a WaveNet decoder could be built for phone calls, as those still sound awful. If it's possible to do this only on the decoder side you don't have to wait for your network to start supporting HD voice or VoLTE to get better quality audio!

I'm curious as to how fast the WaveNet decoder is? The last time I saw an article on it, it took multiple minutes to generate a second of audio.

The original WaveNet repeated a lot of computations; with caching/dynamic programming, it became a lot faster. Other optimizations were also doable. In any case, that was eventually made moot by using model distillation to train a wide flat (not deep) NN, which is 20x realtime: https://deepmind.com/blog/high-fidelity-speech-synthesis-wav... (This was necessary to make it cost-effective to deploy onto Google Assistant.)

Re: Codec2: A Whole Podcast on a Floppy Disk

#65

Post by namibj »

gsich wrote: post #60
namibj wrote: post #58

Earlier quoted context omitted.

The bad thing was that it used lossy compression when copying. That was the problem.

No. The bug was when using the "Scan to PDF" function. It happened on all quality settings. Copying (scanning+printing in one step, no PDF) was not effected.

I remember differently, but I don't want to pull up the source right now.

I did check some of the sources, but was not able to find the one I remember which had statistics on it.

The xerox FAQ to it does lead me to consider that I might be confusing this with some other incident though, as they claim that Scanning is the only thing that is affected.

Re: Codec2: A Whole Podcast on a Floppy Disk

#66

Post by gwern »

MrRadar wrote: post #21

Codec2 is also fully open source and patent-free, in contrast to virtually every other ultra-low-bitrate voice codec (which are proprietary and have expensive patent licensing attached). He has a Patreon if you want to support him in the ongoing development of Codec2 and his SDR modems to enable use of it in amateur radio: https://www.patreon.com/drowe67

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

Re: Codec2: A Whole Podcast on a Floppy Disk

#67

Post by namibj »

gsich wrote: post #62
namibj wrote: post #59

Earlier quoted context omitted.

Also why no one really appreciated ISDN over here in central Europe. Yes, there are ways to do better _now_, and it would have been trivial to support channels with better codecs by negotiating something different than u-law 8kHz PCM, but back then that resulted in rather good quality. The issue was that few people got ISDN phones, which resulted in them using analog outputs on an adapter device, which got later inco…

>Also why no one really appreciated ISDN over here in central Europe. Except Germany. Which had probably the best telephone system in the world when they deployed ISDN nationwide.

I am speaking as a German. Sure, larger businesses used proper ISDN, but your uncle/mom didn't. The best you could hope for there was only DECT compression, aka ADPCM 4bit/8kHz.

Re: Codec2: A Whole Podcast on a Floppy Disk

#68

Post by namibj »

gsich wrote: post #61
IshKebab wrote: post #20

Earlier quoted context omitted.

Actually if you're lucky and make a phone call with HDVoice, or whatever they're calling it, the quality is excellent. It makes a huge difference. Unfortunately the place where you really want good quality is call centres - it's often hard to hear people and half of the reason is the shitty POTS quality - and call centres will probably get HDVoice in about 40-50 years. Maybe. Edit: nm should have read all of your com…

What do you mean with "HDVoice"? On landline connections this usually means G722. G711u/a is definitly not "HD".

I assume the usual wideband codecs used with VoLTE.

Re: Codec2: A Whole Podcast on a Floppy Disk

#69

Post by yoklov »

sitkack wrote: post #51
CharlesW wrote: post #18

Earlier quoted context omitted.

> As far as I know, enough podcast apps require MP3 (and not even VBR!) that you have to use MP3… Nope! Podcast episodes can be encoded using AAC (which is as ubiquitous as MP3) without issue. That won't realistically possible with Opus until Opus hardware decoding has available in mobile devices for 5-10 years.

Distribute podcast as HTML file with WASM based decoder, whole file, self contained with either a byte stream out or play/pause

Ignoring other issues, this will have rather poor power usage, which is especially relevant given how many people listen to podcasts on mobile devices.

Re: Codec2: A Whole Podcast on a Floppy Disk

#70

Post by andai »

Hello71 wrote: post #38
CharlesW wrote: post #18

Earlier quoted context omitted.

> As far as I know, enough podcast apps require MP3 (and not even VBR!) that you have to use MP3… Nope! Podcast episodes can be encoded using AAC (which is as ubiquitous as MP3) without issue. That won't realistically possible with Opus until Opus hardware decoding has available in mobile devices for 5-10 years.

I highly doubt there are any devices that are capable of accessing the modern web, with all its JavaScript bloat, yet cannot decode a simple audio codec. Even when Apple was installing AAC hardware decoders, they were already almost obsolete by modern embedded CPU development (especially the rise of medium-power ARM SoCs). I highly doubt any devices released in the past 5 years have any sort of fixed-function audio d…

I use Opus on my phone all the time. I was in a place where internet was really expensive, so I'd download and convert things on a Linux server.

In conjunction with youtube-dl I could listen to pretty much anything I wanted, using almost no data.

These days I use it mostly for audiobooks, if storage is limited.

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