IETF Opus codec now ready for testing, That's CELT 0.11 Options

[jmvalin]

We'd like to announce that the Opus codec is now ready for testing. The bit-stream is now is a "pseudo-freeze", which means that unless a problem is found during testing/review, there are no longer any changes planned. The only exception to this are the SILK-mode FEC and the stereo SILK mode, which should be landing in the next few days. Considering that these are not critical features, we felt like the testing phase could already begin.

You can get the source code in two different ways. There is a release tarball at http://jmvalin.ca/opus/opus-0.9.0.tar.gz . You can also extract the source directly from the I-D ( http://www.ietf.org/id/draft-ietf-codec-opus-02.txt ) with the following command:

cat draft-ietf-codec-opus-02.txt | grep '^\ \ \ ###' |
sed 's/\s\s\s###//' | base64 -d > opus_source.tar.gz

Now the Opus codec supports three mores, one of which is identical to CELT 0.11, which was just released (not announced officially yet).

It would be nice if the HA community could help test this codec. Opus targets a very wide range of bit-rates, from 6 kb/s narrowband speech up to 510 kb/s stereo music. Perhaps a 64-96 kb/s stereo music test would be interesting to do. Anyone would like to help?

[LithosZA]

It's linked above— https://people.xiph.org/~greg/opus-tools.zip

Are you using this one?

CODE

C:\opus-tools>opusenc.exe
Usage: opusenc [options] input_file output_file.opus

Encodes input_file using Opus. It can read the WAV, AIFF, or raw files.

General options:
-h, --help This help
-v, --version Version information
--quiet Quiet mode

input_file can be:
filename.wav file
- stdin

output_file can be:
filename.opus compressed file
- stdout

Encoding options:
--speech Optimize for speech
--music Optimize for music
--bitrate n.nnn Encoding bitrate in kbit/sec (6-256 per channel)
--vbr Use variable bitrate encoding (default)
--cvbr Use constrained variable bitrate encoding
--hard-cbr Use hard constant bitrate encoding
--comp n Encoding complexity (0-10, default: 10)
--framesize n Maximum frame size in milliseconds
(2.5, 5, 10, 20, 40, 60, default: 20)
--expect-loss Percentage packet loss to expect (default: 0)
--downmix-mono Downmix to mono
--downmix-stereo Downmix to stereo (if >2 channels)
--max-delay n Maximum container delay in milliseconds
(0-1000, default: 1000)

Diagnostic options:
--save-range file Saves check values for every frame to a file
--set-ctl-int x=y Pass the encoder control x with value y (advanced)
Preface with s: to direct the ctl to multistream s
This may be used multiple times
--uncoupled Use one mono stream per channel

Metadata options:
--comment Add the given string as an extra comment
This may be used multiple times
--artist Author of this track
--title Title for this track

Input options:
--raw Raw input
--raw-bits n Set bits/sample for raw input (default: 16)
--raw-rate n Set sampling rate for raw input (default: 48000)
--raw-chan n Set number of channels for raw input (default: 2)
--raw-endianness n 1 for bigendian, 0 for little (defaults to 0)

This post has been edited by db1989: Jul 3 2012, 17:30

Reason for edit: Please use [codebox] for large items, not [quote].

[zerowalker]

Had done something entirely else XD

But got it working with that one now, using cmd etc.

And from my tests,

OPUS Is better than Autov with keeping details on characteristic things, like a singers dark voice etc, while Autov fails here and "blend" everything to make it smooth or something.

The Good thing with this is, you get more detail on these parts, the bad thing is, you get more "cracks etc" in the "surroundings".


Sorry for bad explanation, not the best listener nor explainer on this kind of stuff.
But that´s atleast what i got out of it on my tests.


EDIT:

I may take back my statement on which i prefer.

When i listen once again on them, the OPUS does have a Fuller more Concrete sound, while Autov like i said about, pretty much smooth things out to keep it "transparent".
I think that if i just play awhile i will ignore those crack sounds and it will be pretty pleasent really.

Though it´s not like i am going to sit and listen to 45 kbit music here, but it´s really neat that it´s moving forward on the Transparent/Size scale.

From what i would prefer, i think i would go with Autov as it´s more Transparent with the cracks and overall smoothness in the sound, though i really like the way opus keeps the details on stuff, but sadly the cracks is to much to be pleasent.

Settings where for one example: --framesize 60 --music --bitrate 45, Autov = q-1
Went after the filesize.

This post has been edited by zerowalker: Jun 1 2012, 00:48

[rt87]

aoTuV Q -1 is 48kbps.

This post has been edited by db1989: Jul 3 2012, 17:29

Reason for edit: deleting pointless full quote of above post