Audio Matters at ROUGOL, Mon 19th Oct 2020

The next meeting of the RISC OS User Group Of London (online) is:

Audio Matters, presented by Jason Tribbeck

Monday 19th October 2020, 7.45pm

Online via Zoom, meeting open from 7.30pm

http://www.rougol.jellybaby.net/meetings/

One of the (many!) things often bemoaned as missing from the RISC OS sound system is a standardised method for audio input. This was less of a problem when extra hardware (podule) was needed as they came with their own software, but with many of the new systems having audio input facilities it has become more important to define a standard way to access them.

After being contacted by the Cloverleaf Project, Jason Tribbeck has stepped forward and started working on a new audio input API. His investigations have quickly expanded into looking at the audio system as a whole.

His goals are to:
- Allow audio input
- Support multiple interfaces at the same time
- Have higher resolution formats
- Provide backward compatibility with what has been done before

Jason will be talking about how he plans to achieve these aims, with some digressions into unit testing and documentation too! There is a long discussion and links to his (very detailed) proposal documents in this thread . Have a read through and bring along your thoughts and questions.

This meeting will be held online via Zoom. Please contact us to receive a link to the meeting on the day.

http://www.rougol.jellybaby.net/contacts/

At the risk of being boringly predictable I’d like to repeat my view that a key part of development should be integrating the use of USB Audio devices for playback and audio capture so they can be chosen by the user at the OS level for connection to audio applications via their standard interface.

That would open up RO to what other OSs have taken as standard for years and enable the use of external hardware which can deliver high quality, etc.

WRT Documentation. When changes are made I’d be happy to generate an updated and expanded version of the old ‘ROSS Document’ to suit. Just need the changes and the details explained to me in suitably chosen words. :-)

Sorry if it is bad form, but could someone link the meeting URL please, as I’m sat poised with zoom open, but haven’t heard back from Bryan (due to my lateness) – only 5 mins to go!

Glad we got there in time! I had forgotten to keep a watch for last minute email requests.

Anyone know when a video of the meeting will appear on YT?

Anyone know when a video of the meeting will appear on YT?

You could try checking here every so often until it appears.

Snag is that usually I use NetSurf when using RO. So I’ve been looking at the ROUGOL pages as I assume(d?) the info would appear there first.

Still no offers of pantomime… :-)

Patience young padawan :-) We have kept Leo rather busy with video editing over the past few months – ROUGOL meetings are not short! And then there was the 9 hours of the London Show to sift through…

So I’ve been looking at the ROUGOL pages as I assume(d?) the info would appear there first.

Well, it will always have to appear on YouTube first, as Leo has to upload it and then let me know so I can update the website. But it’s hopefully only a brief delay between those two events.

Apologies, my Master. I will try to curb my youthful eargerness. :-)

Yes, I take the point about the show in particular as I still haven’t managed to watch all of it. Excellent. I confess to having a keen interest in the audio and it makes me antsy as I wait as I think I’ll find it specially interesting.

More power to Leo.

The best things come to those who wait :-) Video – https://youtu.be/F-PhWFiKitk

Hooray. :-)) Many Ta’s!

Thanks for uploading this!

I haven’t had time to watch properly yet, and not sure if Jason’s looking at this thread, but I noted the comments about Maestro and SoundChannels. I wondered if anything other than Maestro has ever actually used this interface, and, if not, would it be easier to modify Maestro to use a new API rather than go to all the effort of keeping support for the old one?

I haven’t had time to watch properly yet, and not sure if Jason’s looking at this thread, but I noted the comments about Maestro and SoundChannels. I wondered if anything other than Maestro has ever actually used this interface, and, if not, would it be easier to modify Maestro to use a new API rather than go to all the effort of keeping support for the old one?

If you’re referencing SoundChannels specifically, anything from the BBC, pretty much every pre-RiscPC game, of course the system beep, and many little sound playing tools. If you’re talking about SoundScheduler, then at least some of my own tools used the scheduler interface for sound. The SoundChannels interface may be old and tied to 8bit mu-law, but nobody’s (TTBOMK) replaced it. If you want to play polyphonic sounds by pitch and duration (rather than specifically playing samples), you’re going to want to use SoundChannels and that interface.

It’s not actually that hard to emulate the mu-law sound system; as Jason suggsets, you just move where in the control flow that part of the sound system lives.

On the subject of replacing it with a separate API, the SoundChannels interface itself is replaced by an implementation that calls MIDI in Pyromaniac. The standard voices are mapped to GM instruments that are approximately similar. See https://pyromaniac.riscos.online/pyromaniac/CONFIGOPTIONS.html#configuration-group-sound for the configuration detail; https://pyromaniac.riscos.online/pyromaniac/FEATURES.html#sound for feature description.

Ah, OK, sounds like it’s popped up in plenty of places then. I only mentioned it as I tinker with Maestro when I (rarely) get a bit of spare time, mostly to improve its score typesetting, but one day it might be nice to see if its unreliable playback could be improved a bit too.

I’d like to talk with Jason via email, but I don’t know his email address. Failing him reading this, can someone please let him know? He can find my email address on my webpages, etc. So far I’ve only watched the first half or so of the ROUGOL video, though! :-)

to see if its unreliable playback could be improved a bit too.

It uses the sound scheduler to dump a bunch of notes to play into a queue each poll.

Given that Maestro appears to be really broken, it might be worth looking to see about adding some logging for what it is trying to schedule and when, to see if it’s Maestro or the scheduler itself…because I don’t remember it being that bad back in the Archie days.