libv4l2: error dequeuing buf: Input/output error

libv4l2: error dequeuing buf: Input/output error

[bifferos]

Hi all,

Can anyone give any clue as to why I might get this error 
when capturing from a PAC207 webcam?  It happens after a 6-7 
second delay when capturing.

I've seen this with 2.6.30.1, 2.6.30.5 and 2.6.32-rc7, however 
I can run the same camera on another (much faster) system using 
the same kernel(s) and same gspca driver and it works fine, 
making me think this is a timing issue.

I'm testing with the v4lgrab.c program, compiled statically 
against libv4l2.  A quick google indicates I'm not the only
one encountering the problem. 

thanks,
Biff.


      

Re: libv4l2: error dequeuing buf: Input/output error

[Sean]

There have been some improvements to gspca_main and gspca_pac207 
recently, as well as pac207 specific improvements in libv4l2. Are you 
using the latest v4l-dvb and libv4l2? I get some slowdown halfway when 
using capture-example.c and it seems to improve when I use the latest 
v4l-dvb and libv4l2 from mercurial. http://linuxtv.org/hg/v4l-dvb

Sean

bifferos wrote:
> Hi all,
>
> Can anyone give any clue as to why I might get this error 
> when capturing from a PAC207 webcam?  It happens after a 6-7 
> second delay when capturing.
>
> I've seen this with 2.6.30.1, 2.6.30.5 and 2.6.32-rc7, however 
> I can run the same camera on another (much faster) system using 
> the same kernel(s) and same gspca driver and it works fine, 
> making me think this is a timing issue.
>
> I'm testing with the v4lgrab.c program, compiled statically 
> against libv4l2.  A quick google indicates I'm not the only
> one encountering the problem. 
>
> thanks,
> Biff.
>
>
>       
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