Re: [libdc] iSight camera, debian squeeze libdc1394 2.1.3: YUV format problem?

[Max B. <max...@un...>]

Stefan,

I have the newer firewire drivers.  The older ones were not in my  
debian kernel.

I have now tried to make kernel 3.0 and 2.6.38.8 downloaded today from  
kernel.org.  Both failed at boot time with kernel panics.

I have attempted to make the modules with the 2.6.32 kernel source and  
transfer the modules to the working kernel /lib/modules area by hand.   
When I try to use the old modules with the dc1394 examples, the  
library fails to initialise, even though I ./configure'd it before I  
make'd it.  I'm at wit's end right now with this.

Xv is likely not the problem.  The failure is the same when I use the  
non-Xv example programs.

I think the problem lies elsewhere, or _you_ wouldn't have failure  
with grab_color_image but success with grab_color_image2.  Check the  
source code for each.  Why does the former malfunction?  I would like  
to see your output (offlist?) when it malfunctions.  If possible, take  
reproducible images like of an all-red and/or all-blue image.

Thanks for the support!

Cheers,
Max




Stefan Richter <st...@s5...> a écrit :

> On Aug 03 Max BLANCO wrote:
>> Incidentally, debian squeeze is kernel 2.6.32 while the gentoo kernel
>> is 2.6.38.
>
> I am not using Gentoo's kernel, but kernel.org's kernel-of-the-month with
> the development version-of-the-week of firewire kernel drivers.
>
> I haven't had the iSight very long yet and don't remember which is the
> oldest kernel version that I tested it with.  Besides the iSight I have
> another entry-level IIDC camera, Unibrain Fire-i, which I have been using
> with older kernels too.
>
> There are two sets of IEEE 1394 drivers in kernel 2.6.32:
>   - Old but mature ohci1394 + ieee1394 + video1394 + raw1394,
>   - new, in 2.6.32 still immature firewire-ohci + firewire-core.
> libdc1394 v2 is able to work with either set of drivers, transparently to
> the client application.
>
> It is possible that Debian's 2.6.32 kernel package comes with one or the
> other or both sets of drivers.  Please check which ones you have loaded:
>
> 	lsmod | grep -e 1394 -e firewire
>
> If you have both sets of drivers loaded, the system is badly configured;
> but it wouldn't be an actual problem source.  In this (unlikely but
> possible) case you can find out which set of drivers is actually bound to
> the hardware by
>
> 	grep -e 1394 -e firewire /proc/interrupts
>
> If you have the older set of drivers loaded, you should be good.  These
> drivers may contain some bugs but are supposed to generally work for IIDC
> capture in this version of the kernel.  Nevertheless, you could try to
> unload them and load the newer drivers instead, which of course only works
> if the Debian package contains them.
>
> 	modprobe -r raw1394
> 	modprobe -r video1394
> 	modprobe -r ohci1394
> 	modprobe firewire-ohci
>
> On the other hand, if you have the newer drivers loaded, then you should
> definitely try to switch to the older ones.
>
> 	modprobe -r firewire-ohci
> 	modprobe video1394
> 	modprobe raw1394
>
> If your installed 2.6.32 package only contains the newer drivers, that
> would be bad.  Get a newer Debian kernel package then.  It is possible to
> install a newer kernel alongside your existing one (and keep all your
> installed Debian Squeeze userland), but I am not informed about the steps
> involved and the possible pitfalls.
>
> Independently of the question which sets of IEEE 1394 kernel drivers you
> use, you may consider to update the kernel anyway.
>
> That said, as David noted the issue may also lie somewhere else, e.g. in
> libXv.
> --
> Stefan Richter
> -=====-==-== =--- ---==
> http://arcgraph.de/sr/
>



-- 
Max Blanco
CNRS/LASMEA Post Doctoral Research Fellow
Blaise Pascal University
Campus des Cezeaux
63000 Clermont-Ferrand, France
T: +33(0)4 73 40 72 57
F: +33(0)4 73 40 72 62