HydrogenAudio

Lossy Audio Compression => Other Lossy Codecs => Topic started by: silver_cpu on 2002-05-13 19:32:59

Title: About ATRAC compression
Post by: silver_cpu on 2002-05-13 19:32:59
In all honesty, I really like the ATRAC audio format.  Very handy, small size, with excellent sound reproduction quality.  My question is this:

ATRAC3 for the pc can be downloaded off the internet, off of www.minidisc.org (http://www.minidisc.org), no less.  However, no matter how much I scour the net, I can't find ATRAC4.5, which is the newer version of the codec used in Sony's new minidisc decks.  Anyone know where I can find this?  I'm quite eager to try it out
Title: About ATRAC compression
Post by: Doug on 2002-05-13 20:10:18
To quote the MiniDisc FAQ on the same site...

Quote
Sony has chosen a confusing naming scheme for their variations of ATRAC. All Minidisc equipment before the advent of MDLP used ATRAC1 of some generation or another (note the lack of a space between ATRAC and the number 1). We should really be calling the ATRAC of the MZ-1 (Sony's very first MD machine) ATRAC1 version 1.0, for the MDS-501 (the first high-end MD deck) ATRAC1 version 2.0, etc. By this nomenclature, Sony's current MD decks (ca. 2001) are using ATRAC1 version 4.5 and ATRAC1 Type R. MDLP uses a new and incompatible encoding called ATRAC3 version 1.0, which we shorten to just ATRAC3 (note again the lack of a space between ATRAC and the 3).


So in fact your not using an older generation of ATRAC your using a different version of ATRAC to the one used as standard on MiniDics.

I'm not sure where you found the download for an ATRAC3 encoder/decoder as I would be interested in giving the format a look. My Sony laptop came supplied with their OpenMG jukebox software that encoders and decoders music in the ATRAC3 format and provides a decompressor in the Windows ACM. I've had a MiniDisc for a few years and I've generally found the quality of the compression to be more than acceptable to me. What I'm interested in is seeing if there is any SDKs/code for developers to incorporate ATRAC3 technology into their software as I'm sure my audio system could use another codec
Title: About ATRAC compression
Post by: JohnV on 2002-05-13 21:28:35
ATRAC3 download:
http://www.minidisc.org/atrac3.zip (http://www.minidisc.org/atrac3.zip)

It's ACM codec. Unzip the two files and right click atrac3.inf and choose install.
Title: About ATRAC compression
Post by: silver_cpu on 2002-05-15 06:24:29
Yup yup  Now, is there a copy of the version used in today's professional minidisc decks?
Title: About ATRAC compression
Post by: rjamorim on 2002-05-15 06:38:16
Quote
Originally posted by silver_cpu
Yup yup   Now, is there a copy of the version used in today's professional minidisc decks?


AFAIK, the latest ATRAC1 version (4.5) is not available in any software form.

You can test latest Atrac3 (PPL say it's better than the ACM version, never tested it myself) in RealProducer Plus 8.51, @ 105kbps and up. (Besides, it has much more bitrate options, up to 352kbps. The downside is that it produces .ra files instead of Wave. Use .ra plugin for Winamp to play these)

Regards;

Roberto.

Edit: You can get .ra plugin for Winamp here:
http://www.inf.ufpr.br/~rja00/ireal16.exe (http://www.inf.ufpr.br/~rja00/ireal16.exe)
But you must have Real Player 8 installed... :/
Title: About ATRAC compression
Post by: guruboolez on 2002-05-15 09:33:27
Note that ATRAC codec seems to be much better in OpenMG software (Sony, bundled with NetMiniDisc), especially in low bitrate (LP4 = 66 kb/s).
Title: About ATRAC compression
Post by: Doug on 2002-05-15 19:43:28
Well I guess you could expect this to be the case, I doubt Sony would just give away their prized MiniDisc ATRAC codec without some issues attached.

Although RealProducer and OpenMG use the ATRAC3 codec would I be correct in assuming that there is no open file format using the ATRAC codec unless you use the ACM to encode an ATRAC3 compressed wave file.
Title: About ATRAC compression
Post by: theduke on 2002-05-15 20:24:48
I have wondered some time ago how ATRAC is quality wise. How does it compare to other codecs? Is it similar to good MP3s?
Title: About ATRAC compression
Post by: rc55 on 2002-05-15 22:22:10
Evaluating ATRAC would be a tricky task - what with its strange versioning system and implementations. ABX'ing it would be difficult as it would require an optical link, and a number of players to verify the quality.

I'd also be sceptical about the claims made by minidisc.org (unconfirmed - I havent been there for a while).

I doubt an evaluation would occur for a while because most ATRAC implementations are either hardware based or locked up in DRM formats.

Ruairi
Title: About ATRAC compression
Post by: guruboolez on 2002-05-15 22:35:10
The new MiniDisc (NetMD) are different. A user can encode his CD with a fast Pentium or Athlon, and transfer it with USB. Most user do that. So, the « good » or « real » ATRAC3 codec is not longer the hardware codec, but the software codec (OpenMG codec, much better than old crappy ACM codec).

The only problem is to play encoded files in PCABX. I use TotalRecorder for that job.


...sorry for english...
Title: About ATRAC compression
Post by: Doug on 2002-05-15 22:59:02
Although we only have a ACM codec for programmers to directly use it should be enough to use for testing even if the quality isn't as good as other implementations of the ATRAC3 codec. Maybe a new ATRAC3 based format could be created and be contained within an Ogg stream as the existing formats are all inaccessible to most developers. Even if ATRAC is a good compression format we can't use it very well because there is nothing beyond a few select programs that most of us don't use (I assume) to play the compressed files back.
Title: About ATRAC compression
Post by: silver_cpu on 2002-05-16 02:41:29
Thanks for the posts, folks, it's much appreciated.  I'm always happy when I come here, I always find helpful info

Also, just so that you know, the ATRAC3 codec that I was using was the ACM, which produced ATRAC3 .wav files that could be played in any .wav player, provided that you had the ATRAC codec in your system path.  That would make A/B testing quite easy, I'm guessing.  And I was quite happy with the quality of the encodings, although I was totally unaware that you could transfer the files via USB....I'm almost tempted to get a MiniDisc portable player

Unfortunately, there's no way for me to try that out, without buying a NetMD MD player, and I have no intention of doing so without knowledge of how it'll sound.  I really wish that Sony would let you purchase the encoder seperately, for say $20, and simply use it on your computer, and be able to transfer the files if you happen to have a MD player.  Ah, but I doubt that'll ever happen.  And I am NOT going to install RealCrap on my computer, I wouldn't piss on their software for fear of complimenting it.