On 22/06/2012, at 7:14 AM, [email protected] wrote: > Can anyone give me a bit of advice ... I'm trying to set up a webcam. > When I connect to the camera using cheese, lucview or xcam, the > picture is black for the first few frames, and gradually adjusts until > the picture is visible. > > v4lctl snap gives me a black picture. > > I suspect that during the first few frames after opening the device the > camera is doing some auto-exposure adjustment. > > Is there any way anyone knows of getting a picture (programmatically) > and allowing the camera to adjust its aperture/shutter speed or > whatever it does? I've tried webcam and webcamd but they just deliver > black pictures. > > The obvious attempt to take two pictures in a row gives two black > pictures. > > $ v4lctl snap jpeg 320x240; v4lctl snap jpeg 320x240
Tries to rack brain ... This was an issue of recent years ... v4l did not load the camera libraries (relied on kernel, but kernel stopped doing that), but cheese etc did. One needed to run LD_RELOAD somev4l_compatlib v4lctl snap jpeg 320x240; v4lctl snap jpeg 320x240 to get past the black camera I'll dig for accurate detail if you think that this applies to you. James-- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
