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Wavelet-transform based audio codec

Has anyone heard about any wavelet-transform based audio codec?

I know two still-image codecs and one video codec, but have not heard about audio codecs yet. for some reason I believe that wavelet-transform will do a good job for audio. (in particullar, will introduce less pre-echo)

edit: typos

Wavelet-transform based audio codec

Reply #1
AdaptedWave

http://www.adaptedwave.com/

Unfortunately, the site is gone. There used to be lots of information there and some demo samples. Seems that they will return soon. (hopefully)

Wavelet-transform based audio codec

Reply #2
thanks.

but I wanted to see something working (to steal some ideas and compare achivements  )

Wavelet-transform based audio codec

Reply #3
i would ROCK of wavelets could do the same to audio encoding that it did with still images.
The jpeg2000 is far superior to plain jpeg.
Sven Bent - Denmark

Wavelet-transform based audio codec

Reply #4
Quote
i would ROCK of wavelets could do the same to audio encoding that it did with still images.
The jpeg2000 is far superior to plain jpeg.

Do you have any links to any tests done, JPEG VS JPEG2?

I also think that new methods for achieving transparent lossy audio coding are not necessary just gifted engineers for very fine-tuning.

Wavelet-transform based audio codec

Reply #5
I've seen some examples of Jpeg2000 vs normal JPEG, and beside some extra features like transparancy etc, imho the quallity of the format isnt much better. But it depends on your taste. Its like an Ogg-Vorbis vs MusePack tradeoff: the artifacts Jpeg2000 creates at lower quallity are less severe, but at higher quallity imho normal jpeg rules.

just my 2 cents, altough not really on topic ;-)

about that topic, should efforts indeed not be put on the current encoders, instead of new ones? exept when they are really superior...
[span style=\'font-family:Arial\'][span style=\'color:red\']Life Sucks Deeply[/span][/span]

Wavelet-transform based audio codec

Reply #6
JPEG2000 is not really more efficent than JPEG/JFIF for low compression (if you want image without visual artifacts).

But for highly compressed pictures, jpeg2000 is better than old jpeg. So it is depending on what you are targetting.

A drawback of jpeg2000 is the arithmetic coding.

Wavelet-transform based audio codec

Reply #7
Quote
A drawback of jpeg2000 is the arithmetic coding.

why is this a drawback? doesn't it work fast enough on most modern hardware?

Wavelet-transform based audio codec

Reply #8
Arithmetic coding rocks !  I wonder why the lamers over at Intel haven't yet introduced 1-2 new instructions to speed it up ? 

Wavelet-transform based audio codec

Reply #9
Because it is quite hard to implement, it is strongly patended (holders agreed to give free licensing for use in jpeg2000), and it is quite slow (problem for embedded devices running on dsp).

But regarding compression, it is a powerfull tool.

Wavelet-transform based audio codec

Reply #10
It takes only some thought, a few hours and 30-50 lines of code to implement your own form of bitwise arithmetic coding.

With bitwise coding, and a given predictor, you can encode any data in the (asymptotically) optimal way..

Arithmetic coding cannot be patented, only some of its implementations can. If someone tried to patent the concept, then the patent is not valid.

Yes, too bad it's a bit slow..  but with the current machines, I don't think that's a big deal anymore (except for video probably).

Wavelet-transform based audio codec

Reply #11
there are patent-free opensource implementations. like this.

and it seems that speed won't be an issue at the time when jpeg2000 will be widely adpoted

Wavelet-transform based audio codec

Reply #12
Actually, the great issue about speed concerns the predictor, not the coder itself.

Patents have to include both predictor and coder, thus with your own predictor, you should be safe.

Here's a fixed version of the link from X-Fixer:  http://datacompression.info/ArithmeticCoding.shtml


Wavelet-transform based audio codec

Reply #14
I do not think that you can implement a jpeg2000 encoder without falling into IBM patents. The fact that some implementation are free of use regarding the code copyright does not change anything regarding the patents.
(but IBM has agreed to offer free license agreement for use in compliant products).

Speed is still a problem for embedded devices, as is something needs more processing power to be done, it means reduced battery life.

But I think that we are really getting off-topic.

Wavelet-transform based audio codec

Reply #15
I think Intel's Indeo audio codec is wavelet-based.

Intel being Intel, there are probably a few dozen Indeo technical spec sheets and white papers buried deep in the bowels of their humongous web site.

Wavelet-transform based audio codec

Reply #16
Yes, range coding comes very close to arithmetic coding in compression, is much faster, and is believed to be patent free.  There are some papers and code here and here (this is actually the implementation that is used in Monkey's Audio).

Josh

Wavelet-transform based audio codec

Reply #17
Quote
Quote
i would ROCK of wavelets could do the same to audio encoding that it did with still images.
The jpeg2000 is far superior to plain jpeg.

Do you have any links to any tests done, JPEG VS JPEG2?

I also think that new methods for achieving transparent lossy audio coding are not necessary just gifted engineers for very fine-tuning.

sorry no link for a REAL objective test.

but i have test myself. but onyl with hi-res pcitures (1400x1400)
i i hav teste with 11 cd covers i have scanned by the following way

Scan in 600dpi (hardware)
cut it to 2800x2800
lite blurre effekte (to remove scale effect)
resample to 1400x1400
save as jpeg/jpeg2k at around 350kbytes

jp2k gives visual MUCH better quality here.

i did it in PSP 7.04
Sven Bent - Denmark

Wavelet-transform based audio codec

Reply #18
Quote
I think Intel's Indeo audio codec is wavelet-based.

Intel being Intel, there are probably a few dozen Indeo technical spec sheets and white papers buried deep in the bowels of their humongous web site.

Intel sold all their audio and video codecs to Ligos.
http://www.ligos.com/indeo.htm

You won't find any info on Indeo at Intel's site, except links to Ligos' site.
And I believe you won't find any techinfo at Ligos' site either.

Regards;

Roberto.

Wavelet-transform based audio codec

Reply #19
Quote
Yes, range coding comes very close to arithmetic coding in compression, is much faster, and is believed to be patent free.  There are some papers and code here and here (this is actually the implementation that is used in Monkey's Audio).

yes, that's what I've actually meant. rangecoding is also used in La (I believe), PPMd (used in WinRAR and 7-Zip also) and (almost?) any other PPM or BWT archiver (e.g. bzip).

also, I've tested LureWave codec a while ago (not exactly a jpeg2k, but they are doing a jpeg2k codec now afaik). it gave a lossless compression somewhat worse than PNG, but lossy mode was really better than JPEG (for same filesizes on good quality) and the artifacts were less annoying ("loss of details" instead of "blockness" and "Gibbs effect").

if anyone is interested in real comparasion (and ready to provide test data) I guess I still can do it. though, real jpeg2k test would be more interesting

back on topic: I don't believe that Indeo uses wavelets, because it's rather old and generally... sucks. 

Wavelet-transform based audio codec

Reply #20
Nothing really beats PNG in lossless RGB encoding og RGB pictures

There are not many other formats supporting more then 32bits color. or 8 bit alpha channels.
and the compression factor is the best for lossless.
Sven Bent - Denmark

Re: Wavelet-transform based audio codec

Reply #21
Nothing really beats PNG in lossless RGB encoding og RGB pictures

There are not many other formats supporting more then 32bits color. or 8 bit alpha channels.
and the compression factor is the best for lossless.
WebP does beat PNG as it's straight outta '90s so as its homepage. PNG uses zlib to compress which is very old. WebP uses more advanced techniques for compressing losslessly, it also beats JPEG in lossy compression (tech used for lossy compression is similar to the VP8 codec).

https://developers.google.com/speed/webp/docs/compression

Re: Wavelet-transform based audio codec

Reply #22
well it was more than 15 years since that comment, so...
some ANC'd headphones + AutoEq-based impulse + Meier Crossfeed (30%)

Re: Wavelet-transform based audio codec

Reply #23
Yeah, and if you use a better PNG encoder, it a file will be a bit smaller (still lossless).

BTW, JPEG XL is coming. And it seems very promising. It has lossless mode also.

Re: Wavelet-transform based audio codec

Reply #24
(by the way, that part of that message which says that WebP beats JPEG in lossy mode is also incorrect, because lossy WebP is only possible to use with chroma subsampling, and with many images this never allows it to achieve visually lossless result at ANY quality parameter, while JPEG can scale to nearly lossless if you let it use enough bits)
some ANC'd headphones + AutoEq-based impulse + Meier Crossfeed (30%)

 
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