Rawaudio dev

[dingodoppelt]

Add a new "raw" audio quality setting

This PR adds uncompressed audio ("raw") to the quality settings so there is no Opus compression along the way
Discussion in #3654

This feature improves latency as well. I gained 2ms by using uncompressed audio while having a better audio quality.

CHANGELOG: Add uncompressed audio transmission - dedicated to the memory of Hans Petter Selasky (1982 - 2023)

Does this change need documentation? What needs to be documented and how?
Corresponding PR in jamulussoftware/jamuluswebsite #1133

Checklist

• I've verified that this Pull Request follows the general code principles
• I tested my code and it does what I want
• My code follows the style guide
• I waited some time after this Pull Request was opened and all GitHub checks completed without errors.
• I've filled all the content above

[ann0see]

I'd prefer not to check for the Jamulus version number but rather based on capabilities - we don't have 4.0.0 out yet and it might break during the dev process.

[dingodoppelt]

I'd prefer not to check for the Jamulus version number but rather based on capabilities - we don't have 4.0.0 out yet and it might break during the dev process.

I wanted to reuse information already available as much as possible so I just added the code where there were version checks already implemented. (For sequence number and pan feature)
Capabilities would be nice but also would require more changes to client, channel, server and protocol which I don't really have an idea on how to make that backwards compatible. We should rather replace all version checks with some capabilities struct that client and server can agree upon so everything lands in one place. I just don't feel like the right person to take on that challenge and rather pursue my hacky approach, as long as it works for everybody.
The version check with 4.0.0 could be replaced by a point release 3.11.1 and would work right away.

[ann0see]

Tested it and yes, the noise would be unacceptable. What is our fallback if max is selected but the server doesn't support it?

[dingodoppelt]

Tested it and yes, the noise would be unacceptable. What is our fallback if max is selected but the server doesn't support it?

I just noticed that if you connect to a server with Max selected you get the noise unless you switch audio quality again while connected. The server code is fine and doesn't need changes, I misplaced the check for my introduced bRawAudioSupported in the client code. I'll have a closer look
Edit: Funny, the noise doesn't happen on legacy servers, only on rawaudio :D

[dingodoppelt]

I guess this is in a working state now and the only issue remaining is the infrequent unclean exits especially on macOS. As it might even be unrelated to this pull request and I don't have an idea what causes it, I'll set this PR to "ready for review" now.

[dingodoppelt]

As far as I understood these sentinel bytes come from the opus codec itself and are not deliberately set by Jamulus as a message ID of sorts. I'd have to overwrite actual audio bytes for that to work with my code. Or am I wrong here?