Set up a Webcam with Linux

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Revision as of 12:31, 26 December 2020 by ThorstenStaerk (talk | contribs)
Set-up-a-webcam.png

You want to set up your webcam with Linux, see a video stream from it and learn which applications you can use with it, right? Then this article is for you.

Try it

First let's try if it works out of the box, so, connect your webcam (if it's not inbuilt), open a terminal and start the application cheese:

cheese

This should switch on your webcam and you should see what it's recording.

Ok, you are reading on, so there is still something left, maybe:

Install cheese

To install cheese, you need to know your distribution. Here is how to find out your distribution.

  • for Debian, Raspbian, Ubuntu, Kubuntu, Flubuntu, Xubuntu, GEUbuntu, Edubuntu, ...:
sudo apt-get install cheese
  • for SUSE:
yast -i cheese

Check the Setup

If cheese starts, but does not find a webcam, you need to dig deeper.

<source>

ls -ltr /dev/video*

</source>

  • you will find an output like this:

<source>

crw-rw----+ 1 root video 81, 0 Nov 11 09:06 /dev/video0

</source> In this example your webcam device is named /dev/video0. If you have no /dev/video file, read #Troubleshooting. If you have several video4linux devices, for example a tv card your webcam may show up as /dev/video1 or whatever. But the time (in this case Nov 11 09:06) will be the time when you plugged it in.

You can also test your webcam the following ways:

  • if you have vlc installed you can start it and choose Media -> Open Capture Device -> Video device name = /dev/video0 -> Play
  • if you have mplayer installed you can use the command

<source>

mplayer tv:// -tv driver=v4l2:width=640:height=480:device=/dev/video0 -fps 30

</source>

Troubleshooting

Troubleshooting heavily depends on the distribution and version you are using. If you have done cabling correctly and a device file /dev/video* does not appear, your kernel probably does not know the hardware. In this case you may have to install the device driver separately because it may not be part of the kernel.

SUSE Linux 11.0 and earlier

This has been tested with SUSE Linux 11.0 x64 but should work with any earlier SUSE version. You will need to log in as user root. To find out what driver you need, open a console and call

hwinfo --usb

If a Logitech Quickcam Messenger is plugged in the answer will be like: <source highlight=23> 06: USB 00.2: 0000 Unclassified device

 [Created at usb.122]                
 UDI: /org/freedesktop/Hal/devices/usb_device_46d_8da_noserial_if2
 Unique ID: Eopr.vE+cdFBwClB                                      
 Parent ID: uIhY.uOe2OKugI8D                                      
 SysFS ID: /devices/pci0000:00/0000:00:1a.2/usb3/3-1/3-1:1.2      
 SysFS BusID: 3-1:1.2                                             
 Hardware Class: unknown                                          
 Model: "Logitech QuickCam Messanger"                             
 Hotplug: USB                                                     
 Vendor: usb 0x046d "Logitech, Inc."                              
 Device: usb 0x08da "QuickCam Messanger"                          
 Revision: "1.00"                                                 
 Driver: "snd-usb-audio"                                          
 Driver Modules: "snd_usb_audio"                                  
 Speed: 12 Mbps                                                   
 Module Alias: "usb:v046Dp08DAd0100dc00dsc00dp00ic01isc02ip00"    
 Driver Info #0:                                                  
   Driver Status: quickcam_messenger is active                    
   Driver Activation Cmd: "modprobe quickcam_messenger"
 Driver Info #1:                                                  
   Driver Status: gspca is active                                 
   Driver Activation Cmd: "modprobe gspca"
 Config Status: cfg=new, avail=yes, need=no, active=unknown       
 Attached to: #20 (Hub)

</source> This means you can install and load the webcam driver like this:

yast -i gspcav-kmp-default
modprobe gspca

Now you should see a video device:

ls /dev/video*
/dev/video  /dev/video0

That means you can install and start your webcam-viewer-software. We choose gqcam:

yast -i gqcam
gqcam

It works. You see a video what from what is going on in front of your webcam.

Ubuntu

This has been tested with Ubuntu 8.10 x32 but should work with any Ubuntu version. Find out the driver activation command of your webcam. For this, first install the software hwinfo. Open a console and type:

sudo apt-get install hwinfo

Then call hwinfo:

hwinfo --usb

If a Logitech Quickcam Messenger is plugged in the response will be like: <source highlight=20> 04: USB 00.2: 0000 Unclassified device

 [Created at usb.122]
 UDI: /org/freedesktop/Hal/devices/usb_device_46d_8da_noserial_if2
 Unique ID: 4ajv.vE+cdFBwClB
 Parent ID: k4bc._Mkd+LmXb03
 SysFS ID: /devices/pci0000:00/0000:00:11.0/0000:02:00.0/usb1/1-1/1-1:1.2
 SysFS BusID: 1-1:1.2
 Hardware Class: unknown
 Model: "Logitech QuickCam Messanger"
 Hotplug: USB
 Vendor: usb 0x046d "Logitech, Inc."
 Device: usb 0x08da "QuickCam Messanger"
 Revision: "1.00"
 Driver: "snd-usb-audio"
 Driver Modules: "snd_usb_audio"
 Speed: 12 Mbps
 Module Alias: "usb:v046Dp08DAd0100dc00dsc00dp00ic01isc02ip00"
 Driver Info #0:
   Driver Status: gspca_zc3xx is active
   Driver Activation Cmd: "modprobe gspca_zc3xx"
 Config Status: cfg=new, avail=yes, need=no, active=unknown
 Attached to: #8 (Hub)</source>

Activate the driver:

sudo modprobe gspca_zc3xx

Now you should be able to see the video device:

ls /dev/video*
/dev/video0

You can now test your webcam using the software cheese:

sudo apt-get install cheese
cheese

Other webcams

If you have another webcam, try the above nevertheless. If it does not work, exchange the driver gspca against uvcvideo:

yast -i uvcvideo_kmp_default
modprobe uvcvideo

and start gqcam again.

Use it

record video

to capture video streams you can use cheese, a nice program with a graphical user interface. It allows you to watch and record your camera output at the same time. It stores in a strange format (.webm), but vlc can play this.

You can also automate video recording so you can capture the camera stream with sitting in front of the computer. To do this you can

  • use the software mencoder:

<source>

mencoder tv:// -tv driver=v4l2:width=320:height=240:device=/dev/video0 -nosound -ovc lavc -o myvideo.avi

</source>

  • or use the software streamer, example:

<source>

streamer -c /dev/video0 -f jpeg -F stereo -o myvideo.avi -t 0:05

</source>

video conferencing

watch it

To watch your camera's input, use cheese or mplayer: <source>

mplayer -fps 30 -cache 128 -tv driver=v4l2:width=640:height=480:device=/dev/video0 tv://

</source> Or use vlc. You can run vlc as root by the way. To watch your webcam /dev/video0, start vlc and select Media -> Open Capture Device -> Video device name = /dev/video0 -> Play

Testbed

The following webcams have been found working with this tutorial:

  • Logitech Quickcam messenger
  • Philips Webcam SPC220NC

A general list of working webcams can be found at http://mxhaard.free.fr/spca5xx.html.

The guide has been tested with SUSE Linux 11.4 till 13.2 and Ubuntu.

See also