Re: [Coriander-devel] v4l2loopback for coriander

[Gordon S. <go...@gy...>]

Dear Stefan

I agree I think it is the way forward, but as i have 13 mouths of my
doctorate left and simply do not have the time for now but after i
graduate i will look at my schedule.

all the best

gordon







On Sun, 2012-06-03 at 13:08 +0200, Stefan Richter wrote:
> On May 29 Gordon Sinclair wrote:
> > I have invested in a couple of very nice firewire cams which give me 30
> > fps. I need to get them to work through coriander to my program using
> > the v4l interface. That's when it all went wrong because the V4L1 API
> > was removed in one of the Linux 2.6.38 pre-releases. The
> > <linux/videodev.h> header doesn't exist any more and has been superseded
> > by <linux/videodev2.h>. Thus I cannot build vloopback on my system with
> > the kernel version 2.6.38-15-generic-pae
> > 
> > Is there a branch of coriander which does v4l2loopback?
> > 
> > I have taken a look at the code for vloopback but I don't understand it
> > at all. The only other option is to roll back to a previous kernel.
> 
> Doing FireWire video capture via special low-level IEEE 1394 I/O kernel
> interfaces instead of the V4L/ V4L2 interface has been, and still is, one
> of the big mistakes of IEEE 1394 support on Linux.
> 
> The stop-gap solution for 1394 video via V4L, vloopback, was always
> problematic by
>   (a) being a project outside of the mainline kernel, thus risking
>       breakage at any kernel update,
>   (b) having to rely on a userspace process for DMA buffer queueing.
> The very same problems apply to v4l2loopback of course.
> 
> To me, an IIDC to V4L2 kernel driver (as well as an IEC61883-2/-4 to V4L2
> kernel driver) looks like a much more useful project.  Alas I have far to
> little time for Linux projects myself for the time being to implement such
> a driver.