Yalac - Comparisons, How the evaluation release compares to other compressors Options

[TBeck]

Content

In this thread the testers should post comparisons of the preset modes of Yalac (Working name for "Yet another lossless audio compressor") with other lossless compressors.

The results for specific variations of individual encoder options should go into the thread " Yalac – Evaluation and optimization".

Guidelines

Please post the exact version number of the compressors. Compression ratio should be specified in percent of the uncompressed file size. Speed figures should be specified as multiple of real time (duration of the test files). A specification of your test system, especially the CPU, would be helpful.

Open end: Feel free to add more results later.

What happened

Bad timing of my introduction (April 1.) forced an early publication of an evaluation release of Yalac, to prove, that it really works. This are results of 8 forum members, who where so kind to test the experimental release for me.

Many thanks!

Goals

Yalac should finally achieve compression ratios on par with Monkey's Audio High. Decoding speed should be at least two times higher than Monkey and never be significantly lower than with FLAC (possibly Yalac will later be integrated into FLAC).

My next steps

The first results i have received from the testers show me some weaknesses of the encoder. That's a good thing, because that means, that there definitely is a chance to increase the compression efficiency! Same is true for the speed; especially the decoder is not fully optimized yet. But it will take some time, before i will come up with an optimized release.

Links to 24 bit files i have used

I think, they are hard to find.

CODE

44 KHz, 24 bit

mytek_8X96_24bit_web.wav
Mytek-stereo96adc_evans.wav
Mytek-stereo96adc_ravel.wav

Source: http://www.mytekdigital.com/compare/comparison1.htm

48 KHz, 24 bit

McDougalsMen24bit_48kHz.wav
sister24bit_48kHz.wav

Source: http://ff123.net/samples.html

Or make a better Google search. foosion shows you how: http://www.hydrogenaudio.org/forums/index....ndpost&p=381702

This post has been edited by TBeck: Apr 12 2006, 20:23

[Synthetic Soul]

Following my comparison using 16bit 44.1KHz stereo tracks I had started preparing for a comparison using the same tracks converted to mono, and also 48KHz and 24 bit.

Is it worth me continuing with this?

I am also wary that you, Thomas, are currently in the process of changing things around a fair bit. I wonder whether I might do better to hold off until you release these changes?

That said, I am, of course, happy to help if you would like more variety in your results. I just don't want to be wasting my time really, if you feel that you already have enough data for the current run.

[TBeck]

Following my comparison using 16bit 44.1KHz stereo tracks I had started preparing for a comparison using the same tracks converted to mono, and also 48KHz and 24 bit.

Is it worth me continuing with this?

I am also wary that you, Thomas, are currently in the process of changing things around a fair bit. I wonder whether I might do better to hold off until you release these changes?

That said, I am, of course, happy to help if you would like more variety in your results. I just don't want to be wasting my time really, if you feel that you already have enough data for the current run.

Very nice!

But good that you have asked:

1) More mono tests aren't necessary for my purposes. It's good that one tester has confirmed my own findings.

2) 48 Khz vs. 44 Khz shouldn't change much.

3) If i convert 16 to 24 bit files with Cooledit, it only does shift the original lower bits 8 bits up and fills the free space (the new lower 8 bits) with 0. If you try such files with YALAC, you will only find, that YALAC doesn't look for this special case (an option sometimes called 'Look for wasted bits') and will perform very bad compared to other compressors. The implementation of such a check is easy but not done yet.

Real 24 bit files would be far more interesting.

I surely will ask for more specific tests, if there are improvements, that are worth the effort.

This should not stop testing! Other files can always give surprising results, which give me hints for further improvements.

One important note:

I tend to write too much about my actual improvements. But they are only prototypes! It will take a considerable amount of time to optimize and debug them! There will be no considerably improved releases within the next weeks! Speedups are a different matter, they may come fast.

I tend to forget, how long it did take, to built the actual YALAC.

Thomas

This post has been edited by TBeck: Apr 18 2006, 14:20