Difference between revisions of "Webcam setup"

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[[Category:Imaging]]
 
[[Category:Imaging]]
[[Category:Other hardware]]  
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[[es:Webcam setup]]
[[ru:Webcam Setup]]
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[[ja:ウェブカメラ設定]]
[[zh-CN:Webcam Setup]]
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[[ru:Webcam setup]]
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[[zh-hans:Webcam setup]]
 
This is a guide to setting up your webcam in Arch Linux.
 
This is a guide to setting up your webcam in Arch Linux.
  
== Linux webcam support ==
+
Most probably your webcam will work out of the box. Permissions to access video devices (e.g. {{ic|/dev/video0}}) are handled by [[udev]], there is no configuration necessary.
  
Most probably your webcam will work out of the box. In that case you may skip to section [[Webcam_Setup#Webcam configuration]] if you want to configure color, brightness and other parameters. Otherwise follow the steps below.
+
== Loading ==
  
== Identify your webcam ==
+
Identify the name of your webcam (using, for example, {{Ic|lsusb}}) and find a proper driver. See [https://www.linuxtv.org/wiki/index.php/Webcam_devices Webcam devices] for the details about drivers.
Identify the name of your webcam (using, for example, {{Ic|lsusb}}) and find a proper driver. Below is a list of webcams, and what drivers they work with. Click on the link to the right of the device name for information on compiling modules and other information. If you get your webcam to work, add the name of the webcam and the driver you used to the list!
 
  
=== pwc ===
+
Add your webcam's [[kernel module]] in {{ic|/etc/modules-load.d/webcam.conf}} so it will be loaded into the kernel during init stage bootstrapping.
* Creative Labs Webcam Pro Ex
 
* Logitech QuickCam Notebook Pro (only the "Pro" models)
 
* Logitech Quickcam Pro 4000
 
* Philips ToUCams (not confirmed at the moment, but it is using the pwc driver if I remember correctly)
 
* Philips SPC900NC
 
  
=== [[qc-usb]] ===
+
If your webcam is USB, the kernel ''should'' automatically load the proper driver.  If this is the case, check dmesg after you plug your webcam in. You should see something like this:
* Dexxa Webcam
 
* Labtec Webcam (old model)
 
* LegoCam
 
* Logitech Quickcam Express (old model)
 
* Logitech QuickCam Notebook (not the "Pro" models)
 
* Logitech Quickcam Web
 
 
 
=== qc-usb-messenger ===
 
* Logitech Quickcam Messenger
 
* Logitech Quickcam Communicate (for Communicate MP/S5500 or "for Business" see the linux-uvc section below)
 
 
 
It is now in the community repo.
 
 
 
'''Note:''' If qc-usb-messenger does not work use the gspca module, by installing the gspcav1 package.<br>
 
'''Note:''' Now this driver is a module included in kernel 2.6.27
 
 
 
=== zr364xx ===
 
This driver can be used for many webcams like:
 
* Aiptek PocketDV 3300
 
* Creative PC-CAM 880
 
* Konica Revio 2
 
* Genius Digital Camera
 
* Maxell Maxcam PRO DV3
 
You can find the full list of supported devices [http://royale.zerezo.com/zr364xx/ here]. You can find a PKGBUILD for this driver in the [[Arch User Repository|AUR]].
 
 
 
=== sn9c102 ===
 
* Trust Spacecam series
 
* Maxell Smartcam (for notebooks): 352x288 max. resolution @ 3fps
 
 
 
=== gspca ===
 
An extensive list of supported webcams is available [http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=blob;f=Documentation/video4linux/gspca.txt;hb=HEAD].
 
 
 
'''''Note:''' This driver does not have V4L1 support.''
 
 
 
=== stv680 ===
 
Many cheap no-name cameras that came out Asia in the last couple of years use the stv680 chipset. Most of these cameras were novelty items (i.e. Pencam, SpyC@m and LegoCam).
 
* Aiptek PenCam series
 
* Digitaldream series
 
* Dolphin Peripherals series
 
* Lego LegoCam
 
* Trust SpyC@m series
 
* Welback Coolcam
 
 
 
A more-complete list of webcams that use the stv680 chipset is available [http://webcam-osx.sourceforge.net/cameras/index.php?orderBy=controller here].
 
 
 
=== linux-uvc ===
 
* Genius iLook 1321
 
* Logitech  Webcam C250
 
* Logitech  Webcam C270
 
* Logitech  Webcam C600
 
* Logitech Quickcam Pro 5000
 
* Logitech Quickcam Pro 9000
 
* Logitech Quickcam Orbit AF
 
* Logitech Quickcam Orbit MP
 
* Logitech Quickcam S5500
 
* Microdia Pavilion Webcam (on MSI PR200)
 
* Logitech Quickcam Communicate MP/S5500 or "for Business"
 
* Chicony Electronics CNF7051
 
 
 
You can find a full list of supported UVC devices [http://linux-uvc.berlios.de/ here].
 
 
 
As of kernel 2.6.26 linux-uvc is part of the kernel. Just load the uvcvideo module.
 
 
 
{{Note|This driver does not have V4L1 support.}}
 
{{Note|With WebCam SCB-0385N (usb ID 2232:1005), WebCam SC-0311139N (usb ID 2232:1020) and WebCam SC-03FFL11939N (usb ID 2232:1028), you might need to add some configuration to the module if the usage of the camera makes the system freeze :
 
{{hc|1=/etc/modprobe.d/uvcvideo.conf|2=options uvcvideo nodrop=1}} }}
 
 
 
=== ov51x-jpeg ===
 
* Sony EyeToy
 
* Chicony DC-2120
 
* Chicony DC-2120 pro
 
* Trust Spacecam 320
 
* Hercules Webcam Deluxe
 
* Hercules Webcam Classic
 
* Creative Live! Cam Notebook Pro VF0400
 
* Creative Live! Cam Vista IM
 
* Creative Live! Cam Vista IM VF0420
 
* Creative Vista Webcam VF0330
 
* ASUS webcam Model?
 
* Philips PCVC820K/00
 
* NGS showtime plus
 
* HP VGA Webcam with Integrated Microphone
 
 
 
This is a kernel module found in the AUR with some additions to the original driver that provide jpeg decompression.
 
 
 
For me to get my "Creative Live! Cam Vista IM" working with Skype, I had to add this line to {{ic|/etc/modprobe.d/modprobe.conf}}:
 
options ov51x-jpeg forceblock=1
 
 
 
=== r5u870 (Ricoh) ===
 
* HP Pavilion Webcam
 
* HP Webcam 1000
 
* Sony VAIO VGP-VCCx
 
 
 
The Ricoh webcam is built into most new Sony laptops.
 
 
 
Install {{AUR|r5u87x-hg}} (provides firmware too) and run the {{ic|loader}} command.
 
 
 
=== stk11xx (Syntek) ===
 
* Integrated camera in lot of Asus laptops
 
* Asus A8J, F3S, F5R, F5GL, F9E, VX2S, V1S, A6T
 
 
 
Just install the {{AUR|stk11xx}} AUR package. It contains the right kernel module.
 
 
 
== Make sure the module is loaded for your webcam ==
 
Add your webcam's [[Kernel modules#Loading|module]] in {{ic|/etc/modules-load.d/webcam.conf}} so it will be loaded into the kernel during init stage bootstrapping.
 
 
 
'''Note:''' If your webcam is USB, the kernel ''should'' automatically load the proper driver.  If this is the case, check dmesg after you plug your webcam in. You should see something like this:
 
  
 
{{hc|<nowiki>$ dmesg|tail</nowiki>|<nowiki>
 
{{hc|<nowiki>$ dmesg|tail</nowiki>|<nowiki>
Line 138: Line 26:
 
</nowiki>}}
 
</nowiki>}}
  
== Permissions ==
+
== Configuration ==
In order to use your webcam, you need to have permission to use {{ic|/dev/video0}}.
 
  
=== udev ===
+
If you want to configure brightness, color and other webcam parameters (e.g. in the case when out-of-the-box colors are too bluish/reddish/greenish) you may use '''Qt V4L2 Test Brench''' (''qv4l2''), available in the package {{Pkg|v4l-utils}}. Just install it and launch, and it will present you a list of configurable settings. Changing these settings will affect all applications.
If you use [[udev]], you only need to be in the group ''video''. You can check it with:
 
$ groups
 
To add a user to the group run under root:
 
# gpasswd -a <username> video
 
Note the next two steps may not be required as they should already be set by [[udev]]
 
  
Set group of device to video:
+
== Applications ==
# chgrp video /dev/video0
 
Set permissions of the device:
 
# chmod 660 /dev/video0
 
  
=== devfs ===
+
See also [[List of applications/Multimedia#Webcam]].
Add the following to your {{ic|/etc/devfsd.conf}}.  This will give normal users permission to use {{ic|/dev/video0}} (your webcam).
 
# Give normal users access to webcam
 
REGISTER        video0      PERMISSIONS    root.users 0660
 
  
== Webcam configuration ==
+
=== xawtv ===
 
 
If you want to configure brightness, color and other webcam parameters (e.g. in the case when out-of-the-box colors are too bluish/reddish/greenish) you may use [http://guvcview.berlios.de/ GTK+ UVC Viewer] available in the [[Official Repositories]] as package  {{Pkg|guvcview}}. Just install it and launch, and it will present you a list of configurable settings. Changing these settings will affect all applications (e.g. Skype).
 
 
 
== Get software to use your webcam ==
 
 
 
Version 2.6.27 of the Linux kernel supports [http://mxhaard.free.fr/spca5xx.html many new webcam drivers].  Legacy Video4Linux API has been dropped, and these drivers now only support Video4Linux version 2.  Pixel format decoding has been pushed to user space, since Video4Linux version 2 does not support kernel space decoding.  The libv4l library provides userland applications with pixel decoding services and will be used by most programs.  Other compatibility layers are also available.
 
 
 
'''If your device is created but your image looks strange (mine was nearly completely green), you probably need this.'''
 
 
 
If the application has V4L2 support but no pixelformat support (eg: cheese) then use the following command:
 
LD_PRELOAD=/usr/lib/libv4l/v4l2convert.so cheese
 
 
 
If the application only supports the older version of V4L (Skype is the most popular of this kind of software) then use this command:
 
LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so skype
 
 
 
{{Tip|1=You also might want to put a line like the following into {{ic|/etc/profile}} or [[xprofile]] so you do not have to type that long command all the time:
 
{{bc|1=export LD_PRELOAD=/usr/'$LIB'/libv4l/v4l2convert.so}}
 
or
 
{{bc|1=export LD_PRELOAD=/usr/'$LIB'/libv4l/v4l1compat.so}}
 
}}
 
 
 
For 32-bit applications (e.g. Skype) within Arch64, install the {{pkg|lib32-v4l-utils}} package.
 
 
 
If the webcam works fine on guvcview, but it does not work in Skype, you may also need to set
 
export XLIB_SKIP_ARGB_VISUALS=1
 
before starting it.
 
 
 
=== Cheese ===
 
Cheese is the GNOME photo/video taking client.  It is similar to Photo Booth in Mac OS X. It is in the official repositories.
 
  
=== GTK+ UVC Viewer (guvcview) ===
+
This is a basic v4l device viewer, and although it is intended for use with TV tuner cards, it works well with webcams. It will display what your webcam sees in a window. Install it ({{Pkg|xawtv}}) and run it with:
In addition to being a convenient way to configure your webcam, [http://guvcview.berlios.de/ guvcview] also allows capturing (with sound!) and viewing video from devices supported by the Linux UVC driver. Available in the AUR: {{AUR|guvcview}}.
 
 
 
=== Kopete ===
 
Kopete is the [[KDE]] instant messaging (IM) client. As of KDE 3.5, it has support for MSN and Yahoo! webcams, but not every cam works yet. It is included in the kdenetwork package.
 
 
 
=== Kamoso ===
 
Application to take pictures and videos out of your webcam for KDE.
 
Available in the AUR: {{AUR|kamoso}}.
 
 
 
=== xawtv ===
 
This is a basic v4l device viewer, and although it is intended for use with TV tuner cards, it works well with webcams. It will display what your webcam sees in a window. Install it using
 
# pacman -S xawtv
 
Run it with  
 
 
  $ xawtv -c /dev/video0
 
  $ xawtv -c /dev/video0
 
If you are using an nVidia graphic card, and you get an error like
 
If you are using an nVidia graphic card, and you get an error like
Line 212: Line 46:
 
you should instead run it as:
 
you should instead run it as:
 
  $ xawtv -nodga
 
  $ xawtv -nodga
google talk
+
 
 
=== VLC ===
 
=== VLC ===
[[VLC]] can also be used to view and record your webcam. In VLC's file menu, open the 'Capture Device...' dialog and enter the video and audio device files. Or from the command line, do:
+
 
 +
[[VLC]] can also be used to view and record your webcam. In VLC's "Media" menu, open the 'Capture Device...' dialog and enter the video and audio device files. Or from the command line, do:
 
  $ vlc v4l:// :v4l-vdev="/dev/video0" :v4l-adev="/dev/audio2"
 
  $ vlc v4l:// :v4l-vdev="/dev/video0" :v4l-adev="/dev/audio2"
 
This will make VLC mirror your webcam. To take stills, simply choose 'Snapshot' in the 'Video' menu. To record the stream, you add a {{ic|--sout}} argument, e.g.
 
This will make VLC mirror your webcam. To take stills, simply choose 'Snapshot' in the 'Video' menu. To record the stream, you add a {{ic|--sout}} argument, e.g.
Line 225: Line 60:
  
 
=== MPlayer ===
 
=== MPlayer ===
 +
 
To use [[MPlayer]] to take snapshots from your webcam run this command from the terminal:
 
To use [[MPlayer]] to take snapshots from your webcam run this command from the terminal:
 
  $ mplayer tv:// -tv driver=v4l2:width=640:height=480:device=/dev/video0 -fps 15 -vf screenshot
 
  $ mplayer tv:// -tv driver=v4l2:width=640:height=480:device=/dev/video0 -fps 15 -vf screenshot
From here you have to press {{keypress|s}} to take the snapshot. The snapshot will be saved in your current folder as '''shotXXXX.png'''.
+
From here you have to press {{ic|s}} to take the snapshot. The snapshot will be saved in your current folder as '''shotXXXX.png'''.
 
If you want to record continuous video:
 
If you want to record continuous video:
  $ mencoder tv:// -tv driver=v4l2:width=640:height=480:device=/dev/video0:forceaudio:adevice=/dev/dsp -ovc lavc -oac mp3lame -lameopts cbr:br=64:mode=3 -o <filename>.avi
+
  $ mencoder tv:// -tv driver=v4l2:width=640:height=480:device=/dev/video0:forceaudio:adevice=/dev/dsp -ovc lavc -oac mp3lame -lameopts cbr:br=64:mode=3 -o ''filename''.avi
Press Ctrl+C to end the recording.
+
Press {{ic|Ctrl+c}} to end the recording.
 +
 
 +
=== mpv ===
 +
 
 +
To use [[mpv]] to take snapshots from your webcam run this command from the terminal:
 +
$ mpv av://v4l2:/dev/video0
 +
From here you have to press {{ic|s}} to take the snapshot. The snapshot will be saved in your current folder as '''mpv-shotNNNN.jpg'''.
  
 
=== FFmpeg ===
 
=== FFmpeg ===
Line 236: Line 78:
 
See [[FFmpeg#Recording webcam]].
 
See [[FFmpeg#Recording webcam]].
  
=== ekiga ===
+
== Troubleshooting ==
This is very similar to Microsoft NetMeeting.   
+
 
Install the {{pkg|ekiga}} package from the official repositories.
+
=== V4L1 support ===
The configuration druid will set everything up for you.
+
 
 +
Version 2.6.27 of the Linux kernel dropped support for the legacy Video4Linux (1) API.  Pixel format decoding has been pushed to user space, since Video4Linux version 2 does not support kernel space decoding.  The libv4l library provides userland applications with pixel decoding services and will be used by most programs.  Other compatibility layers are also available.
 +
 
 +
'''If your device is created but your image looks strange (e.g. nearly completely green), you probably need this.'''
 +
 
 +
If the application has V4L2 support but no pixelformat support then use the following command:
 +
LD_PRELOAD=/usr/lib/libv4l/v4l2convert.so application
 +
 
 +
If the application only supports the older version of V4L, use this command:
 +
LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so application
 +
 
 +
{{Tip|1=You also might want to put a line like the following into {{ic|/etc/profile}} or [[xprofile]] so you do not have to type that long command all the time:
 +
{{bc|1=export LD_PRELOAD=/usr/lib/libv4l/v4l2convert.so}}
 +
or
 +
  {{bc|1=export LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so}}
 +
}}
 +
 
 +
For 32-bit [[multilib]] applications, install the {{Pkg|lib32-v4l-utils}} package and replace {{ic|/usr/lib/libv4l/}} by {{ic|/usr/lib32/libv4l/}} in the above commands.
 +
 
 +
=== Microsoft Lifecam Studio/Cinema ===
 +
 
 +
Under certain configurations, the Microsoft lifecam studio/cinema may request too much usb bandwidth and fail [http://www.ideasonboard.org/uvc/#footnote-13 see Uvcvideo FAQ]. In this case, change the buffering by loading the {{ic|uvcvideo}} driver with {{ic|1=quirks=0x80}}. Add it to {{ic|/etc/modprobe.d/uvcvideo.conf}} :
 +
 
 +
{{hc|1=/etc/modprobe.d/uvcvideo.conf|2=
 +
## fix bandwidth issue for lifecam studio/cinema
 +
options uvcvideo quirks=0x80
 +
}}
  
=== Sonic-snap ===
+
{{Note|If delays are visible in the logs, or the camera works periodically, this workaround should apply generally. Bigger values such as {{ic|1=quirks=0x100}} are possible.}}
Sonic-snap [http://www.stolk.org/sonic-snap/] is a viewer/grabber for sn9c102-based webcams '''only'''.
 
{{AUR|sonic-snap}} is available in the AUR.
 
  
=== Skype ===  
+
=== Check bandwidth used by USB webcams ===
The newest version of [[Skype]] has video support. Check Video Devices in the options for a test image which you can double-click to make full screen. Install the {{pkg|skype}} package.
 
If you get green/disorted picture with skype read the section [[Webcam_Setup#Get software to use your webcam]] above.
 
  
If your running x86-64 you might actually need to
+
When running multiple webcams on a single USB bus, they may saturate the bandwidth of the USB bus and not work properly. You can diagnose this with the ''usbtop'' tool from the {{AUR|usbtop}} package.
# pacman -S multilib/lib32-v4l-utils
 
and then run skype with
 
LD_PRELOAD=/usr/lib32/libv4l/v4l1compat.so skype
 
You can either set an alias for skype, or rename the original skype binary in {{ic|/usr/bin}} and create a text file containing the above option, or you can simply adjust the Command line in the options for the Skype icon in your favourite desktop environment.
 

Latest revision as of 19:26, 17 May 2018

This is a guide to setting up your webcam in Arch Linux.

Most probably your webcam will work out of the box. Permissions to access video devices (e.g. /dev/video0) are handled by udev, there is no configuration necessary.

Loading

Identify the name of your webcam (using, for example, lsusb) and find a proper driver. See Webcam devices for the details about drivers.

Add your webcam's kernel module in /etc/modules-load.d/webcam.conf so it will be loaded into the kernel during init stage bootstrapping.

If your webcam is USB, the kernel should automatically load the proper driver. If this is the case, check dmesg after you plug your webcam in. You should see something like this:

$ dmesg|tail
sn9c102: V4L2 driver for SN9C10x PC Camera Controllers v1:1.24a
usb 1-1: SN9C10[12] PC Camera Controller detected (vid/pid 0x0C45/0x600D)
usb 1-1: PAS106B image sensor detected
usb 1-1: Initialization succeeded
usb 1-1: V4L2 device registered as /dev/video0
usb 1-1: Optional device control through 'sysfs' interface ready
usbcore: registered new driver sn9c102

Configuration

If you want to configure brightness, color and other webcam parameters (e.g. in the case when out-of-the-box colors are too bluish/reddish/greenish) you may use Qt V4L2 Test Brench (qv4l2), available in the package v4l-utils. Just install it and launch, and it will present you a list of configurable settings. Changing these settings will affect all applications.

Applications

See also List of applications/Multimedia#Webcam.

xawtv

This is a basic v4l device viewer, and although it is intended for use with TV tuner cards, it works well with webcams. It will display what your webcam sees in a window. Install it (xawtv) and run it with:

$ xawtv -c /dev/video0

If you are using an nVidia graphic card, and you get an error like

X Error of failed request:  XF86DGANoDirectVideoMode
 Major opcode of failed request:  139 (XFree86-DGA)
 Minor opcode of failed request:  1 (XF86DGAGetVideoLL)
 Serial number of failed request:  69
 Current serial number in output stream:  69

you should instead run it as:

$ xawtv -nodga

VLC

VLC can also be used to view and record your webcam. In VLC's "Media" menu, open the 'Capture Device...' dialog and enter the video and audio device files. Or from the command line, do:

$ vlc v4l:// :v4l-vdev="/dev/video0" :v4l-adev="/dev/audio2"

This will make VLC mirror your webcam. To take stills, simply choose 'Snapshot' in the 'Video' menu. To record the stream, you add a --sout argument, e.g.

$ vlc v4l:// :v4l-vdev="/dev/video0" :v4l-adev="/dev/audio2" \ 
  --sout "#transcode{vcodec=mp1v,vb=1024,scale=1,acodec=mpga,ab=192,channels=2}:duplicate{dst=std{access=file,mux=mpeg1,dst=/tmp/test.mpg}}"

(Obviously a bit overkill with regard to the bit rates but it is fine for testing purposes.) Notice that this will not produce a mirror on the display - in order to see what you are recording, you would need to add the display as a destination to the argument:

... :duplicate{dst=display,dst=std{access= ....

(Though this can tax older hardware somewhat...)

MPlayer

To use MPlayer to take snapshots from your webcam run this command from the terminal:

$ mplayer tv:// -tv driver=v4l2:width=640:height=480:device=/dev/video0 -fps 15 -vf screenshot

From here you have to press s to take the snapshot. The snapshot will be saved in your current folder as shotXXXX.png. If you want to record continuous video:

$ mencoder tv:// -tv driver=v4l2:width=640:height=480:device=/dev/video0:forceaudio:adevice=/dev/dsp -ovc lavc -oac mp3lame -lameopts cbr:br=64:mode=3 -o filename.avi

Press Ctrl+c to end the recording.

mpv

To use mpv to take snapshots from your webcam run this command from the terminal:

$ mpv av://v4l2:/dev/video0

From here you have to press s to take the snapshot. The snapshot will be saved in your current folder as mpv-shotNNNN.jpg.

FFmpeg

See FFmpeg#Recording webcam.

Troubleshooting

V4L1 support

Version 2.6.27 of the Linux kernel dropped support for the legacy Video4Linux (1) API. Pixel format decoding has been pushed to user space, since Video4Linux version 2 does not support kernel space decoding. The libv4l library provides userland applications with pixel decoding services and will be used by most programs. Other compatibility layers are also available.

If your device is created but your image looks strange (e.g. nearly completely green), you probably need this.

If the application has V4L2 support but no pixelformat support then use the following command:

LD_PRELOAD=/usr/lib/libv4l/v4l2convert.so application

If the application only supports the older version of V4L, use this command:

LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so application
Tip: You also might want to put a line like the following into /etc/profile or xprofile so you do not have to type that long command all the time:
export LD_PRELOAD=/usr/lib/libv4l/v4l2convert.so

or

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

For 32-bit multilib applications, install the lib32-v4l-utils package and replace /usr/lib/libv4l/ by /usr/lib32/libv4l/ in the above commands.

Microsoft Lifecam Studio/Cinema

Under certain configurations, the Microsoft lifecam studio/cinema may request too much usb bandwidth and fail see Uvcvideo FAQ. In this case, change the buffering by loading the uvcvideo driver with quirks=0x80. Add it to /etc/modprobe.d/uvcvideo.conf :

/etc/modprobe.d/uvcvideo.conf
## fix bandwidth issue for lifecam studio/cinema
options uvcvideo quirks=0x80
Note: If delays are visible in the logs, or the camera works periodically, this workaround should apply generally. Bigger values such as quirks=0x100 are possible.

Check bandwidth used by USB webcams

When running multiple webcams on a single USB bus, they may saturate the bandwidth of the USB bus and not work properly. You can diagnose this with the usbtop tool from the usbtopAUR package.