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Driver webcam gspcav2 su Debian con kernel > 2.6.27

Posted: Giugno 24th, 2009 | Author: | Filed under: Hack, Video | Commenti disabilitati su Driver webcam gspcav2 su Debian con kernel > 2.6.27

Il mitico driver, della mia mitica webcam da 9.90€, è dalla versione 2.27 internamente al kernel e distruibuito come modulo, ma purtroppo non funziona subito in quanto le librerie di decoding dei formati dei frame restituiti dal device in esame sono state spostate in user space:

# apt-get install libv4l-0
# zless /usr/share/doc/libv4l-0/README.gz
[…]
FAQ

Q: Why libv4l, whats wrong with directly accessing v4l2 devices ?
[…]
With gspca being ported to v4l2 and thus decoding to normal formats being
removed from the device driver as this really belongs in userspace, ekiga
would need to be extended with many more often chip dependent formats, like
the bayer compression used by the spca561 and the (different) compression used
by the pac207 and the (again different) compression used by the sn9c102. Adding
support for all these formats should not be done at the application level, as
then it needs to be written for each application seperately. Licensing issues
with the decompressors will then also become a problem as just cut and pasting
from one application to another is bound to hit license incompatibilities.

So clearly this belongs in a library, and in a library with a license which
allows this code to be used from as many different applications as possible.
Hence libv4l was born.

Si dovrebbe lanciare un export LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so e poi l’applicazione desiderata: per il mai tramontato mplayer

$ mplayer -fps 15 tv:// -tv driver=v4l2:device=/dev/video0

 Per far funzionare skype che magari parte in automatico nella vostra sessione gnome? tenetevi alla sedia: esiste .gnomerc che può eseguire come un .bashrc comandi da eseguire all’avvio della sessione; quindi

$ cat <<EOF > .gnomerc
> LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so
> EOF

In realtà non so se funziona veramente :-P… adesso proverò


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