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Resampling in userspace and then sending it to the kernel is how it already works.. in ALSA. The only real problem with how ALSA does things is that you can't just switch the output (for example sound card to hdmi) for a running stream. PA solves this by basically being a network package router (bus, switch, "sound daemon", however you want to call it). PulseVideo^H PipeWire, from little i cared to look, is basically the same thing. Another problem with ALSA, as well as PA, is that you can't change the device settings (sampling rate, bitrate, buffer size and shape) without basically restarting all audio. (note: you can't reeealy do it anyway as multiple programs could want different rates, buffers, and such) In my opinion, the proper way to do audio would be to do it in the kernel and to have one (just one) daemon that controls the state of the system. That would require resampling in the kernel for almost all audio hardware. Resampling is not a problem really. Yes, resampling should be fixed-point, and not just because the kernel doesn't want floating point math in it. Controlling volume is a cheap multiply(or divide), mixing streams is just an addition (bout with saturation, ofc). Special cases are one program streaming to another (ala JACK), and stuff like bluetooth or audio over the network. Those should be in userspace, for the most part. Oh, and studio hardware, as they often have special hardware switches, DSP-s, or whatever. Sincerely; I doubt i could do it (and even if i could, nobody would care and the Fedoras would say "no, we are doing what ~we~ want"). So i gave up a long while ago. And i doubt anybody else would fight up that hill to do it properly. Half-assed solutions usually prevail, especially if presented as full-ass (as most don't know better). PS Video is a series of bitmaps, just as audio is a series of samples. They are already in memory (system or gpu). Treating either of them as a networking problem is the wrong way of thinking, IMO. Only thing that matters is timing. PPS And transparency. A user should always easily be able to see when a stream is being resampled, where it is going, etc, etc. And should be able to change anything relating to that stream, and to the hardware, in flight via a GUI. |