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Perceptual audio compression and size/bitrate optimization

For anything relating to music-making on Windows computers, with lots of FAQs. Moderated by Martin Walker.

Perceptual audio compression and size/bitrate optimization

Postby Alex-T » Sun May 01, 2011 2:12 pm

Hi,

I am new on this forum and found it by article devote to perceptual audio compression in MP3. Recently I was searching for tools to decrease audio compression size and bitrate keeping excellent, very good or good quality. I have found this blog post:

http://blog.sevana.fi/optimize-bitrate-and-size-preserving-high-audio-quality-in-tracks-podcasts-tunes-with-aqua-wideband/

As I see there are lots of experts in the community could you guys advise me if you think the approach described in the blog post is feasible, because I am just about to order AQuA for evaluation.

Thanks!
Alex
Alex-T
Posts: 3
Joined: Sun May 01, 2011 12:00 am

Re: Perceptual audio compression and size/bitrate optimization

Postby Mowens800 » Sun May 01, 2011 2:36 pm

Alex-T wrote:Recently I was searching for tools to decrease audio compression size and bitrate keeping excellent, very good or good quality.

It might be useful to know what your end goal is here. What are you starting with and why are you looking to compress it so much. This might help people when commenting on the suitability of such a product to your specific needs and material.

Thanks
Mowens800
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Re: Perceptual audio compression and size/bitrate optimization

Postby Alex-T » Sun May 01, 2011 2:50 pm

Mowens800 wrote:
Alex-T wrote:Recently I was searching for tools to decrease audio compression size and bitrate keeping excellent, very good or good quality.

It might be useful to know what your end goal is here. What are you starting with and why are you looking to compress it so much. This might help people when commenting on the suitability of such a product to your specific needs and material.

Thanks

Thank you for such quick feedback! I have two main (independent) tasks:

- compression of large audio files (there is a recording of a seminar/conference/meeting that is typically recorded at 44kHz and 128kbps and does have capacity for space saving, in fact something like 30% is at least compression overhead and when we are talking about 3-4 hours of audio that's quite a lot)

- audio streaming to Internet and let's say "limited bandwidtch" (like mobile phones) users. If I think that the tool I posted the link about can save 24kbps and decrease audio size that sounds quite good to me, because if one is listening to the audio from a mobile phone and doesn't have unlimited GPRS subscribtion then each additional megabyte is extra cash for the user.

Thank you very much for your time and support!

Alex
Alex-T
Posts: 3
Joined: Sun May 01, 2011 12:00 am

Re: Perceptual audio compression and size/bitrate optimization

Postby Mowens800 » Sun May 01, 2011 3:01 pm

Have you looked at .amr? This is the codec used by mobile phones (voice over GSM) for transmission.

The problem with mobile users may be compatibility of different codecs. I've not looked at your link fully though. But the .amr might help on this front. If you have music involved it may not be suitable to your needs due to the restricted bandwidth.
Mowens800
Regular
Posts: 235
Joined: Thu Jun 16, 2005 12:00 am

Re: Perceptual audio compression and size/bitrate optimization

Postby Alex-T » Sun May 01, 2011 3:16 pm

Mowens800 wrote:Have you looked at .amr? This is the codec used by mobile phones (voice over GSM) for transmission.

The problem with mobile users may be compatibility of different codecs. I've not looked at your link fully though. But the .amr might help on this front. If you have music involved it may not be suitable to your needs due to the restricted bandwidth.

Well, AMR is not cheap, but what is worse - it's royalty based:

http://www.voiceage.com/amr_licterms.php

And yes, you are right... if I have music in the audio to be streamed to a mobile device then voice codec does not fit. Even AMR WB won't help, but again it's royalty based codec: http://www.voiceage.com/amrwbplus_licterms.php

This is why I started looking at AQuA: if I can define let's say I want output audio to have MOS 4 then it will automatically encode my audio with a proper bit rate... I hope :)

Thank you!
Alex-T
Posts: 3
Joined: Sun May 01, 2011 12:00 am