Web lists-archives.com

Re: [Spca50x-devs] Exposure control in zc3xx driver

On Sat, 2008-11-15 at 15:08 +0100, Marcin Drewka wrote:
> Hello

Hello Marcin,

> Recently I bought a Labtec Notebook Webcam.
> Vendor ID: 0x046d
> Product ID: 0x08aa
> Sensor: Hdcs2020
> The webcam is working fine in well-lighted enviroment, hovewer in
> darker rooms the image is very dark and full of noise. All of the
> programs I tried to control webcam parameters via v4l1 (camorama,
> It seems to me that the brightness/contrast controls work only on the
> software side.

The controls adjust the webcam hardware, but we have no documentation
about its sensor. If you may get better images with the ms-win driver,
please, do USB traces with sniffbin (one with full light and an other
one in dark room) and send them to me.

>  There is no real exposure/gain setting in none of the
> programs I tried, since there is no way to adjust the parameters in
> the kernel module (gspca_main, gspca_zc3xx) itself. Tried modparm, dug
> in /sys, but with no success.

The only way to adjust the webcam parameters is to use some v4l2 control
program as v4l2ucp. BTW, did you try to disable the autogain?
> Afaik most webcams can be put in some kind of "night mode" where the
> framerate is reduced, but with longer exposure time image quality in
> low light is better. However, I don't see a way to do it with my
> Labtec Notebook Webcam.

I may know it only from ms-win traces.


Ken ar c'hentañ |             ** Breizh ha Linux atav! **
Jef             |               http://moinejf.free.fr/

This SF.Net email is sponsored by the Moblin Your Move Developer's challenge
Build the coolest Linux based applications with Moblin SDK & win great prizes
Grand prize is a trip for two to an Open Source event anywhere in the world
Spca50x-devs mailing list