Sevana Oy Blog » Intelligibility

How can I test this voice quality measurement software?

admin — Mon, 30 Mar 2009 19:09:20 +0000

Sorry for the pause with our new posts on voice quality! This temporary information gap will be over soon and meanwhile we would like to give an answer to such questions as:

- how can I compare two audio files to test voice quality?

- how can I test my codec for voice quality it provides?

The answer to the questions about is: please use contact information on these matters from here: http://www.sevana.fi/about.php

- is there a demo version I can play with?

Yes, it’s available for download from here: http://www.sevana.fi/audio_speech_codecs_quality_analysis.php

- demo version doesn’t allow comparing files! What can I do?

Please use contact information from here: http://www.sevana.fi/about.php and you may get a fully functioning software for your testing purposes!

- are there any updates to the functionality presented in the demo version?

Yes! There is a new version that actually tells you why there is a quality loss providing quantative feedback! And… you know where to go to inquire that version

Stay tuned!

Is there a voice quality testing software that can compare two audio files? Does it have advantages if compared with existing ones? – Yes, this software already exists! Yes it does have advantages!

admin — Sun, 01 Mar 2009 06:28:24 +0000

All what we have described above has been implemented into a software tool and libraries that allow taking another sight to the problem of voice and audio quality measurement. The method of sound signal quality estimation has shown a number of advantages over known methods of quality evaluation:
-    it is universal since it allows judging the quality of signals from various source and processed in different ways;
-    one can optimize quality estimation signal depending on the purposes:
o    in speed (for example, it is possible to receive rough estimation quickly);
o    in signal type (using different bands for speech signals and sound signals in general);
-    resulting estimations correlate well (and sometimes even catches what the others don’t) with that of well-known stadards (МОS, PESQ);
-    quality estimations received for speech signals can be translated in values of various kinds of intelligibility.

To learn more about software test results, business benefits and integration possibililites please check this page http://www.sevana.fi/audio_speech_codecs_quality_analysis.php

We’ll get back to comparing the new method and providing more information about differences and advantages of it comparing to the other methods in the next post. Stay tuned!

Confused on how to measure voice quality after all? Here is the answer – signal + noise + speech model + analytics = state-of-the-art approach!

admin — Tue, 24 Feb 2009 06:32:31 +0000

Today we would like to propose a yet another concept for voice quality testing and estimation. We believe that a successor for PESQ and other methods should have a generator of test signals that allows sound signal generation according to one of the sound flow models (we explain them in further posts). It can be either a particularized set of sound signals or a signal, received as an output of statistical speech model. Generator’s signal can either be saved for follow-up usage or be exposed to processing and estimation. Bank of signals stores sound data, received as a result of signals’ generator work or from some external sources (you can ask for sample speech models from http://www.sevana.fi). Accordingly, an input of estimation block is a signal of generator directly or one of the bank of signals. Test signal is the input of the synchronizer or of the device under test, which can be for example, a vocoder, compressed/decompressed audio, just an audio/voice file or a communication channel. The output signal of the device under test is an input of synchronizer as well. The synchronizer matches in time initial signal and a processed signal. The synchronized signals in chunks are input into analytical module, which determines the degree of similarity for signals and issues the quality estimation as the measure of similarity between the initial and the processed signals. Misty? The point is that a successful voice quality testing system should have:

- Test signals generator
- Noise signals generator
- Statistical speech model
- Signals syncronizer
- Analytical module

Stay connected and we describe all of these modules in our upcoming blog posts!

Enough articulating – let’s calculate speech Intelligibility!

admin — Fri, 20 Feb 2009 04:35:04 +0000

Referring to the previous post concerning AI (Articulation Index) approach to voice quality measurement we would like to present another one: SII (Speech Intelligibility Index) which is the evolution of AI method. The American Standard ANSI S3.5-1997 includes the speech intelligibility index. It provides 4 measuring procedures on different band groups: 21 critical bands, 18 one third-octave bands, 17 equal by their contribution critical bands and 6 octave bands. The signal/noise ratio is calculated within every band and the total SII coefficient ranged from 0 to 1 is computed.

The speech intelligibility index takes into account only the properties of hearing, not speech production and that is an obvious disadvantage of the method..

More methods to automate voice quality analysis are about to follow in the next posts!

Business Benefits

admin — Sun, 15 Feb 2009 08:53:15 +0000