hi bw, actually my case is a PCI(-E) device driver where there are a maximum of four streams, each with their own L/R channel that i’d like to add a balancer for.
it sounds nontrivial though. i guess i shoudln’t be surprised by this. i wish there was an example i could use. of any kind, really. Thanks, Gagan > On Dec 6, 2024, at 7:20 PM, brianw <bri...@audiobanshee.com> wrote: > > I suggest looking at the arrangement of streams, channels, and properties for > another audio interface where the balance slider appears (and is not grayed > out). > > For general CoreAudio drivers, the channels can be grouped into streams of 1, > 2, or more channels. I'd be curious whether balance only appears on streams > with two channels, or if it appears in more configurations. > > In your case, it seems you have a USB audio device, so the mapping from USB > to CoreAudio is determined by the USB Descriptors. Again, looking at some > other audio interface that support balance should tell you what you need. > > Of course, once you find out the configuration that works for other > interfaces, it may not necessarily be appropriate for your device. > > I've seen multichannel interfaces - eight to ten channels - where every > channel has its own stream (they're all mono streams) or where the channels > were grouped into an eight-channel stream (for the main outputs) plus a > two-channel stream (for the headphones). I cannot recall whether balance > appeared for any of these. > > Besides the streams and channels, looks at the properties for those aspects, > and the values returned for those properties. You might need to use something > like AUHAL or write your own tool to query everything on an interface that > supports balance. That's one way to find out what you need. Of course, with a > USB device, you'll need to know which Descriptors correspond to the CoreAudio > properties. > > Brian Willoughby > > > On Dec 6, 2024, at 5:42 PM, Gagan Sidhu wrote: >> i thought this would have been taken care of by the API, but i guess i would >> need to tell it the pins/gpio/whatever about which one is let and right. >> >> does anyone have good examples i could work off to add this feature? it >> doesn’t seem that apple’s documentation or USB audio driver shows how this >> is done. >> >> https://github.com/i3roly/C-Media/issues/3 >> >> Thanks, >> Gagan > _______________________________________________ Do not post admin requests to the list. They will be ignored. Coreaudio-api mailing list (Coreaudio-api@lists.apple.com) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/coreaudio-api/archive%40mail-archive.com This email sent to arch...@mail-archive.com
