USB webcam++ support for FreeBSD-8-current is soon here

[Hans Petter Selasky]

On Monday 01 June 2009, Markus Rechberger wrote:
> Hi,
>
> On Mon, Jun 1, 2009 at 10:41 PM, Hans Petter Selasky <hselasky at c2i.net> 
wrote:
> > Hi,
> >
> > During the weekend I have almost finished my Userland Linux kernel
> > wrapper with full USB support through the new libusb and Linux' V4L API.
> >
> > Currently compiling: GSPCA based Webcams, USB video class webcams.
> >
> > Technically all V4L Radio/DVB and Webcam devices using USB on Linux can
> > be supported under FreeBSD in userland with little hassle. The only
> > problem is that the Linux kernel code is GPL and not LGPL licensed, so
> > there might be a problem linking with propritary applications ...
> >
> > Almost finished code is available from:
> >
> > svn --username anonsvn --password anonsvn \
> >      checkout svn://svn.turbocat.net/i4b/trunk/usbcam/ulinux
> >
> > NOTE: Not all files are checked in, so running "make clean all" won't get
> > you anything yet.
> >
> > If you want to help out on getting the rest of the Linux Webcam drivers
> > up and running on BSD, then please let me know.
>

Hi Markus,

> does this new libusb support transfers up to 170 mbit?

30MByte/second should be quite possible to transfer to userland. Then we are 
transferring 240 mbit/second. I've seen it is not transfer capacity, but 
rather delay which is the problem.

> I wonder 
> because the synchronous attempt to
> transmit URBs is way to slow for this.

The new libusb in FreeBSD-8-current is asynchronous! I am not using the LibUSB 
v0.1 API, but rather a new one specific to BSD.

> I more or less also have a userspace wrapper for video4linux2 and
> linuxdvb which also works with eg. libusb, libpci
> and works on Apple. On Linux it works with legacy applications by
> using LD_PRELOAD although I still need
> a fast data transfer link to the kernel for USB (which is not provided
> by libusb yet).
> I also have a driver for this already (DVB-C, DVB-T, analog TV, FM
> Radio USB Hybrid dongle).

Would you be interested in merging your code with mine?

--HPS