On Thu, Jun 14, 2012 at 12:54:49PM +0200, Tomas Bodzar wrote: > Hi all, > > have someone working audio input with Qemu on OpenBSD?
IIRC, sdl is play-only. Adding a sndio backend could add record-only support (and possibly better play-only support as well). Qemu is not weired so writing one wouldn't be very complicated. But see below. > qemu-system-i386 -audio-help shows that there are two drivers > available (sdl and wav), but both states 'Does not support capture'. > In Windows 7 guest it shows mic device, but I used qemu-system-i386 > -soundhw hda ......... so it's just presented or is that really > working? > > Can find things like this > https://www.redhat.com/archives/libvir-list/2011-January/msg00335.html > , but there is not hda-duplex in OpenBSD Qemu and searching in > archives doesn't return results yet either. > > Any tips? > Full-duplex is different. Qemu emulates a eap(4) device, ie pci audio device that does DMA block by block. The N-th block in the record stream is recorded while the N-th block of the play stream is played. That's what any software on the gest would expect. Obviously, this can't work because the host requires some buffering as well. So there's no way to get full-duplex audio in a emulator that uses a eap(4) style device as model for audio. Unless we let play and record streams out of sync, in which case full-duplex won't be very useful. If so it's easier to emulate two devices, one for playback and one for recording. The same applies to synchronization, e.g., audio-video synchronization in the case of a play-only device in the guest. What do you try to do? -- Alexandre
