v4l1_compat on Ubuntu12.04LTS

Can you give the output of:

lsb_release -a; uname -a; lsusb

Thanks

Hi, thank you for quick response.
Here are the info you requested (I should have put them first...).

ubuntu@ubuntu:~$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 12.04 LTS
Release: 12.04
Codename: precise

ubuntu@ubuntu:~$ uname -a
Linux ubuntu 3.2.0-23-generic-pae #36-Ubuntu SMP Tue Apr 10 22:19:09 UTC 2012 i686 i686 i386 GNU/Linux

ubuntu@ubuntu:~$ lsusb
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 003: ID 090c:1000 Silicon Motion, Inc. - Taiwan (formerly Feiya Technology Corp.) 64MB QDI U2 DISK
Bus 001 Device 004: ID 5986:03b3 Acer, Inc
Bus 002 Device 003: ID 046d:080a Logitech, Inc. Portable Webcam C905

FYI, the log was taken at Lenovo E420 (which has on-board camera + Logicool C905), booting from USB-memory.

If you install cheese, does it work there?

After I cook the bootable USB memory (by Universal-USB-Installer-1.8.9.4.exe + ubuntu-12.04-desktop-i386.iso), what I have done on the Ubuntu (this time) were:

$ sudo apt-get install subversion
$ svn co http://code.opencv.org/svn/opencv/branches/2.4 (=> Rev. 8312)
$ sudo apt-get install cmake
$ sudo apt-get install build-essential
$ sudo apt-get update
$ sudo apt-get install guvcview
$ sudo apt-get install cheese
$ sudo apt-get update
$ mkdir opencv/release-04
$ cd opencv/release-04
$ cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_DIR=/usr/local ..
     and cmake tells
     "-- V4L/V4L2 NO/YES"
$ lsb_release -a
$ uname -a
$ lsusb
$ guvcview (=> good, on-board camera)
$ guvcview -d /dev/video0 (=> good, on-board camera)
$ guvcview -d /dev/video1 (=> good, Logicool C905)

I have tried with Ubuntu12.04/amd64, but it could not load v4l1_compat like Ubuntu 12.04/i386.

Yes, cheese is fine (with on-board camera) too.

You c an use LD_PRELOAD and preload the compat module, then launch the app you want. Not sure what the issue is if it shows up in cheese and so forth...

$ cheese -d /dev/video0
$ cheese -d /dev/video1
Both fine (cheese complains about Gtk-WARNING, but as for video image, it works fine and I can enjoy effects too).

Thank you for the comments of "LD_PRELOAD" issue.
But as my final goal is to let OpenCV's cmake recognize V4L is supported.

That's because after I install OpenCV lib, everytime when I compile a program which uses USB camera by way of highgui-sub-module of OpenCV library, I probably need V4L support to run the program.

I am trying to use LD_PRELOAD with cmake (and later running the compiled program with OpenCV), but it seems a long way ... So I am trying to find alternative way too B-)

Once again, thank you for all your responses and comments. Further info are really appriciated.

FYI,
I DO NOT NEED to set "LD_PRELOAD" to run guvcview and cheese correctly in my current environment.
(Apart from V4L / v4l1_compat problem, they really work fine ...)

Finally, by adding libv4l-dev to the Ubuntu 12.04, it turns out that programs compiled with OpenCV handles USB camera without v4l1_compat.
So I don't need to fight with LD_PRELOAD ^_^;
I always appeciate your works and wonderful Ubuntu!

Re make OpenCV and it will work