[Qemu-devel] Re: Webcam solution for QEMU

[Arnon Gilboa <agilboa@redhat.com>]

Hello Albert,

First of all, I have done nothing in the qemu project for more than two 
years now. My last contribution to qemu were some usb 1.1 uhci/ohci 
patches for very basic support of webcams and other isochronous devices 
(accepted), and a preliminary patch for usb 2.0 ehci (rejected due to 
high res timer requirement). If I remember it correctly the usb 1.1 
worked reasonably on several webcams (mostly old ones, usb 1.1) and with 
low frames-per-second rate.

I guess since then there were some significant changes in the qemu usb 
code, so I cannot really answer your questions. Anyway, in the following 
week or two I will try to catch up with qemu current usb status and 
update you if I have any insight.

Forwarding your message to qemu-devel, so you may get some smarter answers.
 
Best Regards,
Arnon

Albert Orriols Puig wrote:
>
> Hi Arnon,
>
> I'm Albert Orriols-Puig, an assistant professor at La Salle -- Ramon 
> Llull University (in Spain). Recently, we have started using a 
> virtualization solution based on Open Suse + KVM + QEMU. Currently we 
> have some machines that use this software and host two Windows 
> operating systems: WinXP and Win7. The machines work quite well, that 
> is, we have a quite good performance in both guest OS.
>
> One of the key aspects that we need is to give support to webcams, 
> since our users usually employ skype or similar software to make phone 
> calls. However, we have realized that QEMU does not give direct 
> support for webcams. We have searched for different patches, and found 
> yours, which enables transfers in redirected host USB devices.
>
> We have tried your patch in a machine with the two aforementioned 
> hosts and a couple of logitech webcams. We have realized that the 
> guest OS detected the existence of a webcam, but could not show the 
> images of these webcams. In the WinXP system, the image was in black. 
> In the Win7, he detected the webcam but didn't allow using it since an 
> error popped up indicating that the webcam was blocked by another 
> application. We have searched for other patches that may help us, but 
> we were not successful.
>
> So, I'm contacting you to ask you a couple of questions. First, in the 
> patch notes it is mentioned that the system worked for some USB 1.1 
> and USB 2.0 cameras on XP. Do you remember some of the specific 
> webcams that you tried and worked? If so, could you tell me the models 
> and any tweak you needed to do in the guest OS side to make them work? 
> It would be great if we could make this work even if we have to adapt 
> to particular webcams.
>
> The second question is about the state of the progress on the support 
> of devices in QEMU. I've seen in some forums that there are some 
> people (including you ;)) working on QEMU to give support to different 
> devices. Do you know if there will be new releases to support USB 
> devices in a short time? We are specially interested in webcams, but 
> we would also need other devices as well.
>
> Let me thank you in advance for the time spend on reading this email!
>
>
> Best,
>
> Albert Orriols-Puig, PhD
> La Salle -- Universitat Ramon Llull
> email: aorriols@gmail.com
> web: http://www.albertorriols.net <http://www.albertorriols.net/>
>
>
>