Re: [Qemu-devel] [RFC PATCH 0/2] Add USB Video Class device emulation.

["David S. Ahern" <daahern@cisco.com>]

On 06/08/10 09:34, Natalia Portillo wrote:
> Hi,
> 
> This currently adds an emulated USB webcam compliant with USB Video Class Specification 1.0a.
> 
> It only works on Linux guests and feeds the emulated device using a Video4Linux 2 host device, as long as it supports 320x240 MJPEG format.
> 
> This is a Request for Comments as surely code needs some cleaning or style.
> 
> You can see it working here:
> http://www.youtube.com/watch?v=fzGYvjZzx6E with Linux guest
> http://www.youtube.com/watch?v=_Yo9TWPDXCo with Windows XP Home guest
> 
> To add the device use -device usb-uvc-webcam,device=<path to v4l2 device>
> 
> Regards,
> Natalia Portillo
> 

Attempting to try out your patches, but it's failing with the following:

usb-uvc: Init called
usb-uvc: Trying to open /dev/video0
.usb-uvc: Device opened correctly.
usb-uvc: Querying capabilities.
usb-uvc: Device driver: uvcvideo
usb-uvc: Device name: Laptop_Integrated_Webcam_0.3M
usb-uvc: Device bus: usb-0000:00:1a.7-6
usb-uvc: Driver version: 0.1.0
usb-uvc: Device capabilities: 0x04000001
usb-uvc: Enumerating video inputs.
usb-uvc: Setting video input to index 0
usb-uvc: Video input correctly set.
usb-uvc: Trying to set 320x240 MJPEG.
qemu-system-x86_64: -device usb-uvc-webcam,device=/dev/video0: Invalid
format.


Using ekiga for example I know that 320x240 is ok. I know very little
about the v4l (or video in general). Can you provide some pointers?


Also, I tried a PWC camera which is not a V4L2_INPUT_TYPE_CAMERA and
noticed that video_input_index is used uninitialized in usb_uvc_initfn

David