WebCam: xawtv works, camorama/skype don't

bkeeper · 07-28-2009, 09:55 AM

Hi there,

on the way to become Windooze-free I need to get my webcam working. Oddly, with xawtv I see a moving image from it, works nicely, but camorama complains "unable to capture image" and skype just shows green noise. What can be done about that?

Some details: It's a Logitech Communicate STX webcam and a Dell Latitude D410, running kubuntu with a 2.6.28-11-generic kernel. The webcam ID from lsusb is 046d:08d7. The last bits (not sure what is relevant here, all gibberish to me) of dmesg are

Quote:

[ 101.536206] usb 4-1: new full speed USB device using uhci_hcd and address 2
[ 101.772504] usb 4-1: configuration #1 chosen from 1 choice
[ 101.888421] Linux video capture interface: v2.00
[ 101.922055] gspca: main v2.3.0 registered
[ 101.935598] gspca: probing 046d:08d7
[ 103.603243] zc3xx: probe 2wr ov vga 0x0000
[ 103.647242] zc3xx: probe sensor -> 11
[ 103.647247] zc3xx: Find Sensor HV7131R(c)
[ 103.652356] gspca: probe ok
[ 103.652377] gspca: probing 046d:08d7
[ 103.652396] gspca: probing 046d:08d7
[ 103.652429] usbcore: registered new interface driver zc3xx
[ 103.652436] zc3xx: registered
[ 103.791591] usbcore: registered new interface driver snd-usb-audio
[ 109.263245] zc3xx: probe 2wr ov vga 0x0000
[ 850.625079] [drm:i915_getparam] *ERROR* Unknown parameter 6
[ 852.295336] zc3xx: probe 2wr ov vga 0x0000
[ 877.423257] [drm:i915_getparam] *ERROR* Unknown parameter 6
[ 879.119342] zc3xx: probe 2wr ov vga 0x0000
[ 892.583345] zc3xx: probe 2wr ov vga 0x0000
[ 896.659346] zc3xx: probe 2wr ov vga 0x0000
[ 959.839354] zc3xx: probe 2wr ov vga 0x0000
[ 1579.883413] zc3xx: probe 2wr ov vga 0x0000
[ 1673.951443] zc3xx: probe 2wr ov vga 0x0000

What I had tried is a

Code:

sudo apt-get install gspca-source

but after that, do I need to compile something? If so, how would I do that? People say this cam is supposed to work off-the-shelf with gspca, but in my case it doesn't *snief* So I tried

Code:

sudo apt-get install build-essential
cd /usr/src/
sudo tar xvjf gspca.tar.bz2
cd modules/gspca/
sudo ./gspca_build

but the output is little comforting:

Quote:

REMOVE the old module if present
ERROR: Module gspca does not exist in /proc/modules

CLEAN gspca source tree
rm -r -f *.o decoder/.gspcadecoder.o.cmd decoder/*.o \
.gspca.o.cmd *.o *.ko *.mod.* .[a-z]* core *.i \
*.symvers *.err

COMPILE gspca Please Wait ....!!

INSTALL gspca in the kernel binary tree
mkdir -p /lib/modules/`uname -r`/kernel/drivers/usb/media/
rm -f /lib/modules/`uname -r`/kernel/drivers/usb/media/spca5xx.ko
rm -f /lib/modules/`uname -r`/kernel/drivers/media/video/gspca.ko
install -c -m 0644 gspca.ko /lib/modules/`uname -r`/kernel/drivers/usb/media/
install: cannot stat `gspca.ko': No such file or directory
make: *** [install] Error 1

LOAD gspca in memory
FATAL: Module gspca not found.

PRINT COMPILATION MESSAGES if ERRORS look kgspca.err
make -C /lib/modules/`uname -r`/build SUBDIRS=/usr/src/modules/gspca CC=cc modules
make[1]: Entering directory `/usr/src/linux-headers-2.6.28-11-generic'
CC [M] /usr/src/modules/gspca/gspca_core.o
/usr/src/modules/gspca/gspca_core.c:54:27: error: asm/semaphore.h: No such file or directory
/usr/src/modules/gspca/gspca_core.c: In function ‘spca5xx_ioctl’:
/usr/src/modules/gspca/gspca_core.c:2463: error: implicit declaration of function ‘video_usercopy’
/usr/src/modules/gspca/gspca_core.c: At top level:
/usr/src/modules/gspca/gspca_core.c:2609: error: unknown field ‘owner’ specified in initializer
/usr/src/modules/gspca/gspca_core.c:2609: warning: initialization from incompatible pointer type
/usr/src/modules/gspca/gspca_core.c:2611: error: unknown field ‘type’ specified in initializer
/usr/src/modules/gspca/gspca_core.c: In function ‘spca50x_create_sysfs’:
/usr/src/modules/gspca/gspca_core.c:2769: error: implicit declaration of function ‘video_device_create_file’
/usr/src/modules/gspca/gspca_core.c:2780: error: implicit declaration of function ‘video_device_remove_file’
/usr/src/modules/gspca/gspca_core.c: In function ‘spca5xx_probe’:
/usr/src/modules/gspca/gspca_core.c:4301: error: incompatible types in assignment
make[2]: *** [/usr/src/modules/gspca/gspca_core.o] Error 1
make[1]: *** [_module_/usr/src/modules/gspca] Error 2
make[1]: Leaving directory `/usr/src/linux-headers-2.6.28-11-generic'
make: *** [default] Error 2

Sorry for globbering this post with so much output, but I'm by far not advanced enough to pick just the relevant parts... what can I do? Thank you very much for your time!

Edit: xawtv complains, but works, here's its output:

Quote:

This is xawtv-3.95.dfsg.1, running on Linux/i686 (2.6.28-11-generic)
xinerama 0: 1024x768+0+0
/dev/video0 [v4l2]: no overlay support
v4l-conf had some trouble, trying to continue anyway
Warning: Cannot convert string "-*-ledfixed-medium-r-*--39-*-*-*-c-*-*-*" to type FontStruct
get fences failed: -1
param: 6, val: 0
Error: Object "xawtv" does not have windowed ancestor

Cheers,
bkeeper

jdkaye · 07-28-2009, 11:19 AM

How you get the module is all about what kernel you're using. I'm using kernel 2.6.26 and there's no gspca in the kernel so you have to build the module yourself.

OTOH, the 2.6.30 kernel does contain the gspca drivers so you don't have to do this. Now you're using 2.6.28 so you have to find out if that kernel is like 2.6.30 or 2.6.26.
Cheers,
jdk

bkeeper · 07-29-2009, 10:59 AM

Hi jdkaye,

thanks! So, I searched around, and kernel 2.6.28 should have gspca, as I learned. Yet, with gspca, it doesn't work :-\

Instead of a video, skype showed a green flickering pattern, which helped me to find a workaround, though. :-) xawtv complained about something with v4l, which, if I understand correctly, is an alternative driver to gspca. So what I did is write a tiny shell around my skype:

Code:

export LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so
/usr/bin/skype

telling skype to use v4l instead, and now skype also works all right! :-)

Cheers,
bkeeper :-)

jdkaye · 07-29-2009, 01:38 PM

There are two of these v4l (for older cameras) and v4l2 (for newer ones). It's in addition to the driver, not instead of it.

Quote:

videodev 27520 1 gspca
v4l1_compat 12260 1 videodev

As you see, I have both installed. Anyway if things are working to your satisfaction, that's what counts.
cheers,
jdk

bkeeper · 07-29-2009, 01:51 PM

Hi jdkaye,

to learn something here, what did you quote from, where you see both drivers to be installed?

Thanks!

Cheers,
bkeeper :-)

jdkaye · 07-29-2009, 11:31 PM

Is used

Code:

lsmod

which lists all the modules currently loaded on your system. Give it a try.
cheers,
jdk

Electro · 07-30-2009, 01:11 AM

It seems the kernel already loaded the module. Test with Mplayer. xawtv is only for BT878 based video capture devices. Mplayer is just about for every video capture device. If Mplayer has problems with the web cam, so will Skype. Using web cams with Skype is a trial-n-error process. Some work and others do not work. Though probably some of your problems is Intel graphics.

For any modules that have to be compiled that are outside of the kernel, you have to use the version that works with the kernel version that you are using. The reason for this is each kernel version includes a big significant changes from the previous kernel patch for 2.6.x kernels. You have to check the gspca changelog to make sure the latest version supports your kernel version. If it does not, you either have to downgrade your kernel or use the module that came with the kernel.