KVM: 0.894
graphic: 0.791
peripherals: 0.787
device: 0.735
performance: 0.686
kernel: 0.617
mistranslation: 0.550
semantic: 0.538
user-level: 0.534
vnc: 0.511
virtual: 0.505
socket: 0.453
boot: 0.442
network: 0.421
register: 0.405
ppc: 0.372
architecture: 0.369
VMM: 0.349
PID: 0.341
risc-v: 0.330
permissions: 0.327
arm: 0.290
hypervisor: 0.289
assembly: 0.257
TCG: 0.228
debug: 0.224
i386: 0.222
x86: 0.149
files: 0.099

No picture from USB webcam (kvm 0.13-rc1)

I export my Linux webcam to KVM using the switches "-usb -usbdevice host:046d:0929". The XP guest sees the webcam and the drivers install, but the camera only shows a black image. When I open the camera in Windows Explorer, it says "0 images" and a black image, while on a real XP, it says "1 image" and shows the video from the camera. Same problem with different webcams. Same cameras work fine on a native XP install.

Thanks for the report.

Can you tell me if it works with a Linux guest?

Can you tell me what kind of camera it is (e.g. the descriptors from lsusb -v for the device)?

Since there hasn't been any response to the question in comment #1, and version 0.13 is very outdated nowadays, I'm closing this ticket now. If you've still got USB problems with the very latest version of QEMU, please feel free to re-open this ticket again, or open a new ticket instead.