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1
Thank You, Halb

I've tried harp40_1
sample ftp://ftp.tnt.uni-hannover.de/pub/MPEG/audio/sqam/harp40_1.wav
http://sound.media.mit.edu/resources/mpeg4/audio/sqam/

Agree, 96 kbps wasn't enough for acceptable quality. 128 kbps was easy abxable but differences weren't such annoying as at 96 kbps.

I just released 1.2-beta, incorporating this change. To be more precise, the change I made in build C is fully enabled below 64 kb/s and then gradually phased out between 64 kb/s and 80 kb/s. For now I didn't want to change the behaviour at high bit-rate just to be on the safe side (it's already high quality so I want to make sure I don't make anything worse).
Yes, it's understandable. Glad to see Kamedo2's and my results were useful.

Opus hits 1.2-beta.  :)  Nice.

Also I think build C demonstrates a potential of possible smart adaptive bitrate distribution for LF/HF (in future?). Anyway build C  already does good job here and You guys work hard on AV1 video format so I don't pretend to see drastic quality changes those will require a huge amount of work. (hm, neither I have submited any useful tests in previous months)
2
Any link to any tools and documentation for such thing? In theory alot can be possible but I haven't been able to find solid proof for such thing, like some kind of command line app that modulates the audio.

The documentation is rare, and the software nonexistent as all the software is tailored to compatibility with old formats or based on it.

This paper describes a technique that clearly have much similarity with the one used in DCC:
http://sci-hub.cc/10.1049/jiere.1987.0075

One paper about DCC:
http://sci-hub.cc/10.1109/5.326405

This paper is interesting and relates to posterior developments and more in your line.
http://sci-hub.cc/10.1109/TCE.1985.289904

We also have the streamer cassette that hold up to 160MB but the information is very scarce.
http://www.obsoletemedia.org/streamer-cassette/

And for software I don't know any but you can try to use DRM software to do a proof of concept, DRM as in Digital Radion Mondiale. Although is more tailored to radio transmission it can work quite well in tape as the radio medium is more noisy.

https://en.wikipedia.org/wiki/Digital_Radio_Mondiale
https://sourceforge.net/projects/drm/?source=directory
http://nt.eit.uni-kl.de/static/diorama/index.html
https://github.com/kit-cel/gr-drm

3
Support - (fb2k) / Re: Playback follows cursor not working
Last post by greeneye48 -
In my case, I changed from EVENT mode to PUSH mode and it started working again. I'm never really sure what the different is between these modes but usually one of them will work  ;)
4
Support - (fb2k) / Re: need WASAPI help
Last post by greeneye48 -
Hi - new Win10 PC running latest Creators Update, v1703.  Using the new native Windows 10 USB audio drivers, selecting WASAPI Event Style, music plays though my USB DAC and sounds fine but the progress bar does not move.

Yes, same problem. Also the elapsed time doesn't update, and the frequency range visualization doesn't change. I reported this under another post (Playback doesn't follow cursor, and now the reverse). It's REALLY difficult to use foobar when I can't stop and reset to a certain point, etc. Still haven't seen any responses.

Hmmm... changed Event to Push mode and it works as before....
5
@ IgorC: I did that. Just finished.
I used opus-tools-buildC.zip from your link some posts ago.

I started with herding_calls using --bitrate 96. I was not able to ABX it. For a comparison I used --bitrate 48, and though I succeeded I'd call even the --bitrate 48 result pretty good.

I continued with trumpet and could ABX it using --bitrate 96. I could not ABX it using --bitrate 128.

I was not able to ABX trumpet_myPrince using --bitrate 96. Using --bitrate 48 I could but the --bitrate 48 result is acceptable.

I could ABX lead_voice using --bitrate 96, but not using --bitrate 128 (though I got at 6/8, so there is a chance I could ABX it with a lot more ABXing pain. But some years ago I decided not to do extreme ABXing any more: no fun and questionable significance for practical listening).

The weak point comes with harp40_1. I'd call the --bitrate 96 result pretty annoying, and also the --bitrate 128 result is easy to ABX.

With the exception of harp40_1 I'm really impressed by the quality of the --bitrate 128 and also the --bitrate 96 results.

Some remarks:
  • opus seems to have a good sense for critical situations. The bitrates for these difficult samples were quite a way higher than the average bitrate for the bitrate settings.
  • For my test set of various kind of pop music the average bitrate was ~9 per cent higher than the --bitrate value (for --bitrate 48, 64, 96, 128)
  • For my test set of various pop music the opus track peak value was very often something like 1.36. How can I make sure that clipping is avoided on any device I'd like to play the opus file with?


6
Observation: MOS are on par however  build C was significantly better on two critical samples (Castanets and Linchpin).  Better handling of HF pre-echo on castantets clicking and better on guitar of Linchpin sample (more detail & less distortion on both guitars and bass drum  hitting).

All in all, as for me Build C is way to go at 64 and 96 kbps.  Absolutely yes.
Thanks a lot for taking the time to test this. I just released 1.2-beta, incorporating this change. To be more precise, the change I made in build C is fully enabled below 64 kb/s and then gradually phased out between 64 kb/s and 80 kb/s. For now I didn't want to change the behaviour at high bit-rate just to be on the safe side (it's already high quality so I want to make sure I don't make anything worse).
7
Support - (fb2k) / Re: mactype incompatibility
Last post by スラッシュ -
Ah never mind, turns out I could apply an unofficial MacType patch that seemingly fixes things! Disregard...  :))
8
Thank you for this update! The frame no longer resizes--and keeping the image window open was a great improvement!

A small suggestion--is it possible to remove the top bar from the video window? The one that has the Chimera(EVR) and the minimize/maximize/close buttons.



Thanks again :)
9
Listening Tests / Re: Personal Listening Test of 2 Opus encoders
Last post by RiCON -
@Lumitopia here's a x64 build of FFmpeg N-86248-gcfec0d6475 with @atomnuker psyacoustics patch included along with libopus git master. It's built using media-autobuild_suite (MSYS2 + MinGW + GCC 6.3)
10
Opus / Re: Opusenc's built-in resampler
Last post by saratoga -
I think if your definition of audio quality does not relate to audibility then it is not a useful thing to quantize.