Vgrabbj returns all green image

[Åsmund Hjulstad]

Binary package hint: vgrabbj

Vgrabbj returns an all green image (352x288 pixels). Latest jaunty on a Dell XPS M1330 with built in web camera. AMD64.

$ uname -a
Linux askeladden 2.6.28-11-generic #42-Ubuntu SMP Fri Apr 17 01:58:03 UTC 2009 x86_64 GNU/Linux

$ vgrabbj -d /dev/video0 > test2.jpg
Reading image from /dev/video0
There was no map allocated to be freed...

$ lsusb
Bus 002 Device 002: ID 05a9:2640 OmniVision Technologies, Inc.

v4l-info output attached

[tuxo (beat-fasel)]

System: Kubuntu Jaunty 9.04

I can confirm this bug:

vgrabbj -i vga -d /dev/video0 -f test.png
Reading image from /dev/video0
There was no map allocated to be freed...

The result is a green image.

The camera here is a Logitech QuickCam E 3500.

[tuxo (beat-fasel)]

lsusb returns the following information about the QuickCam E 3500:
Bus 002 Device 007: ID 046d:09a4 Logitech, Inc.

[tuxo (beat-fasel)]

Just noticed that the webcam tool Cheese works fine with my QuickCam E 3500.

[tuxo (beat-fasel)]

I found a workaround for this problem. As proposed in http://n2.nabble.com/Opencv-Samples-in-Linux-environment-td2302179.html, this is achieved by preloading v4l1compat:

LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so vgrabbj -d /dev/video0 -f grab.jpg