The Webcam HOWTO

Howard Shane

<hshane[AT]austin.rr.com>
Revision History                                                             
Revision 1.1           2004-01-12            Revised by: jhs                 
Update for 2.6 series kernel release and info on NW802-based webcams         
Revision 1.0           2003-12-4             Revised by: JP                  
Initial Release / Reviewed by TLDP                                           
Revision 0.5           2003-11-07            Revised by: jhs                 
Final revision after v4l mailing list feedback                               
Revision 0.1           2003-10-12            Revised by: jhs                 
Initial draft posted                                                         


This document was written to assist the reader in the steps necessary to
configure and use a webcam within the Linux operating system.

-----------------------------------------------------------------------------
Table of Contents
1. Introduction
    1.1. Copyright Information
    1.2. Disclaimer
    1.3. New Versions
    1.4. Credits
    1.5. Feedback
    1.6. Conventions Used in this Document
   
   
2. Supporting the Connection Type
    2.1. USB Webcams
    2.2. IEEE 1394 (Firewire??, i.Link??)
    2.3. Generic Parallel Port Support for Parport Webcams
   
   
3. Making and Accessing the Video Device
    3.1. Device Filesystem
    3.2. Creating Video Devices Manually
    3.3. Groups and Permissions
   
   
4. Specific Webcam Models
    4.1. 3com HomeConnect PC Digital Webcam
    4.2. CPiA based Webcams
    4.3. SE401, SE402 and EP800 based USB webcams
    4.4. OmniVision based Webcams
    4.5. Logitech (formerly Connectix) Quickcam Support
    4.6. NW802 Based Webcams
    4.7. Philips USB Webcams
    4.8. STV0680 based Models
    4.9. Winbond w9966cf
    4.10. Xirlink C-it?? HDCS-1000 based Webcams
   
   
5. Framegrabbing Applications
    5.1. Xawtv
    5.2. MoTV
    5.3. Streamer
    5.4. Motion
    5.5. Gqcam
    5.6. camE
    5.7. SANE
   
   
6. Troubleshooting
    6.1. Help, How do I figure out what my USB camera chipset is if the model
        isn't listed in your HOWTO?
    6.2. Help, I can't find the camera device in /dev!
    6.3. Help, I can see the camera device, but I can't access it!
    6.4. Help, my camera has a driver that is source-only, i.e., has to be
        built by me! Where do I start?
    6.5. Help, my camera is supported by a driver that has to be patched into
        my kernel! What do I do?
    6.6. Help--as in, where can I get more of it?
    6.7. Help, I want to contribute to Video4Linux support in Linux! Who do I
        get in touch with?
   
   
A. Gnu Free Documentation License

1. Introduction

This document was written to assist the reader in setting up and configuring
a webcam, digital camera, or other video device in the Linux operating
system. It outlines how to enable the necessary kernel and/or software
support and various frame-grabber applications that can be used to access
your device. It does not discuss the differences in graphic and video
formats, the features and/or capabilities of particular devices, or the
encoding or conversion of video formats.
-----------------------------------------------------------------------------

1.1. Copyright Information

This document is Copyright 2003, by Howard Shane.

Permission is granted to copy, distribute, and/or modify this document under
the terms of the GNU Free Documentation License, Version 1.2 or any later
version published by the Free Software Foundation with no Invariant Sections,
no Front-Cover Texts, and no Back-Cover Texts. A copy of the license can be
found in Appendix A.
-----------------------------------------------------------------------------

1.2. Disclaimer

No liability for the contents of this document can be accepted. Use the
concepts, examples and other content entirely at your own risk. As this is a
new edition, there may be technical or other inaccuracies that may result in
the loss of irreplaceable data. In any case, proceed with caution, and
realize that although errors are highly unlikely, the author can accept no
responsibility for them.

All copyrights are held by their respective owners, unless specifically noted
otherwise. Use of a term in this document should not be regarded as affecting
the validity of any trademark or service mark.

Naming of particular products or brands should not be seen as endorsements.
-----------------------------------------------------------------------------

1.3. New Versions

This is the initial release.

The latest version number of this document can be found [http://
www.hshanemd.net/docs/HOWTOS/Webcam/] here.
-----------------------------------------------------------------------------

1.4. Credits

I would like to thank all of the individuals that have pioneered video
support for linux, in particular the v4l and v4l2 teams, Gerd Knorr, and the
Metzler Brothers among others.

Also, I would like to thank Marla, who has the grace to accept my
imperfections and idiosyncrasies unconditionally, including my obsession with
projects such as this.
-----------------------------------------------------------------------------

1.5. Feedback

Please send any additions or comments pertaining to this document to the
following email address: <hshane[AT]austin.rr.com>. In particular, if you
have information about new devices or interfaces supported or errata, please
contact me so we can keep this document up-to-date!
-----------------------------------------------------------------------------

1.6. Conventions Used in this Document

The following conventions are used in this document and are outlined here for
those who may not yet have a complete understanding of how to access and
control the underlying operating system in Linux, which is almost always via
the Bash shell.

First, filenames are referenced in a paragraph like so: /path/file

Commands in Linux are executed (or 'called') at the command prompt, otherwise
known as the 'command line'. If you are in the non-graphical (text-based)
environment, you will usually be presented with the Bash shell prompt which
is a dollar sign:

+---------------------------------------------------------------------------+
|$                                                                          |
+---------------------------------------------------------------------------+

...or the hash mark:

+---------------------------------------------------------------------------+
|#                                                                          |
+---------------------------------------------------------------------------+

...if you have logged in as root, have acquired root, or 'superuser'
privileges. You can also access the Bash shell in the X window system,
otherwise known as X or X11, with an [http://invisible-island.net/xterm/]
xterm or similar X-terminal-emulator. Commands to be performed at the Bash
prompt, but referenced in a paragraph of this document, usually look like
this: do this now

Commands and/or the resulting output of commands may also be outlined with
screen output in their own paragraph or heading:

+---------------------------------------------------------------------------+
|$ date                                                                     |
|Sun Jul 27 22:37:11 CDT 2003                                               |
+---------------------------------------------------------------------------+

When a command is written in front of the Bash prompt (e.g., $ date above),
it is assumed the [Return] or [Enter] key has been pressed after the command,
possibly followed by the output on a new line (e.g., as in the date in the
above example).
-----------------------------------------------------------------------------

2. Supporting the Connection Type

2.1. USB Webcams

If you have a USB webcam, it is very possible your hardware has at least some
support in Linux. There are two ways of supporting USB devices in Linux. One
is the more tradtional kernel support, and the other is through libusb. If
you would prefer the more conventional kernel support for USB devices, go on
to Section 2.1.2.
-----------------------------------------------------------------------------

2.1.1. Libusb

Libusb is a library that allows access to the USB functions in linux through
userspace and without the need to enable kernel support and insert modules.
Most distributions, at this point, are offering [http://
libusb.sourceforge.net/] libusb in their stable branches (and some install it
by default), so if you don't already have kernel support for USB devices,
then you may only have to install the libusb package in order to access your
device. You must have USB device filesystem support enabled in your kernel,
which most distributions do. To find out for sure, issue the following at the
command line:

+---------------------------------------------------------------------------+
|$ cat /proc/filesystems                                                    |
+---------------------------------------------------------------------------+

You should see (among others):

+---------------------------------------------------------------------------+
|        nodev   usbdevfs                                                   |
|        nodev   usbfs                                                      |
+---------------------------------------------------------------------------+

You may need to mount usbdevfs to enable it and see the device files, which
you can do at the command line with mount -t usbdevfs none /proc/bus/usb.
Don't try to use libusb while your particular kernel webcam support is
enabled either statically or the module loaded; you can only use one at at
time.

You can obtain the libusb package in .rpm, .tgz or .deb format from your
Linux distribution.
-----------------------------------------------------------------------------

2.1.2. Linux Kernel USB Support

Kernel support is required for USB webcam support (if not using libusb). Your
stock kernel may already have support for what you need and the way to tell
is to use the dmesg command and look for an acknowledgement that the driver
in question was loaded at bootup. In general, USB webcams require the module
usbvideo to function. If you don't see it, the driver may be present (but not
necessarily loaded) as a module. To find out, you can type the following at
the command line:

+---------------------------------------------------------------------------+
| $  ls -R /lib/modules/X.XX/kernel/drivers                                 |
+---------------------------------------------------------------------------+

Where 'X.XX' is your kernel version number. The following output is an
example of what you might find in a USB webcam-ready kernel, where everything
is loaded as a module (though all but the relevant lines have been edited for
brevity):

 
+---------------------------------------------------------------------------+
|        ./usb:                                                             |
|        usbvideo.o                                                         |
|        usbcore.o                                                          |
|        ibmcam.o                                                           |
+---------------------------------------------------------------------------+

(A hint for newbies: if the info in dmesg or the above module list scrolls by
too fast, you might try piping the output into 'less' (or 'more' if you don't
have less): ls -R /lib/modules/X.XX/kernel/drivers | less or alternatively
catching it in a file: ls -R /lib/modules/X.XX/kernel/drivers > file.txt,
where 'file.txt' will contain the info that can then be accessed with cat
[file] | less.)

If your kernel doesn't contain the necessary support, you can always
recompile your kernel. If you are unfamiliar with the process of compiling
your own kernel, I direct you to the [http://www.tldp.org/HOWTO/
Kernel-HOWTO.html] Kernel HOWTO for more information.

For generic USB bus support in Linux, you will need USB subsystem support in
your kernel, whether usb-ohci, usb-ehci, or whatever flavor of USB driver
your system prefers. USB subsystem support has been present in the Linux
kernel since the late 2.2 series. For a more in-depth discussion of USB
support in general, I direct you to the [http://www.linux-usb.org/] linux-usb
project site. If you want to find out which modules are loaded, at the
command line or in an xterm, type the following: 

+---------------------------------------------------------------------------+
|# lsmod                                                                    |
+---------------------------------------------------------------------------+

As shown by the prompt above, you will need to have root privileges to do
this. You should get output similar to the following:

+-------------------------------------------------------------------------------------+
|                cdrom                  29312   0  (autoclean) [sr_mod]               |
|                usb-ohci               17888   0  (unused)                           |
|                usbcore                56768   0  [scanner ibmcam usbvideo usb-ohci] |
|                ibmcam                 39680   0                                     |
|                                                                                     |
+-------------------------------------------------------------------------------------+

If you don't have the particular module you're seeking loaded and you know
you have it included as a module in your kernel, try loading it directly
(using the usb ibmcam module as an example):

+---------------------------------------------------------------------------+
|# modprobe -v ibmcam                                                       |
+---------------------------------------------------------------------------+

...at which point you should see something like the following:

+---------------------------------------------------------------------------+
|Using /lib/modules/2.4.20/kernel/drivers/usb/ibmcam.o                      |
+---------------------------------------------------------------------------+

By placing the entry ibmcam (for example) in /etc/modules (note that this
varies by distribution), you can have the module load at boot-time
automatically. You can then confirm the module was loaded by checking the
syslog or in the boot-time record with dmesg | less), where you should see an
entry such as the following:

+---------------------------------------------------------------------------------------------------------------+
|                Oct 18 12:43:12 K7 kernel: hub.c: new USB device 00:02.3-2, assigned address 3                 |
|                Oct 18 12:43:12 K7 kernel: ibmcam.c: IBM PC Camera USB camera found (model 2, rev. 0x030a)     |
|                Oct 18 12:43:12 K7 kernel: usbvideo.c: ibmcam on /dev/video1: canvas=352x240 videosize=352x240 |
|                                                                                                               |
+---------------------------------------------------------------------------------------------------------------+
-----------------------------------------------------------------------------

2.2. IEEE 1394 (Firewire??, i.Link??)

IEEE 1394 webcams require an IEEE 1394 PCI card in your computer for access.
The IEEE interface has been supported in Linux since the early 2.4-series
kernel. If you are lucky enough to own such a device, generic information on
support of the IEEE 1394 bus in Linux can be found at [http://
www.linux1394.org] www.linux1394.org. If you have a kernel older than 2.4.2,
you will need to patch your kernel with one of the patches found on [http://
download.sourceforge.net/linux1394] this page matched to your kernel version.
In addition, you will require [http://download.sourceforge.net/libraw1394]
libraw1394. The previously referenced linux1394.org site has a great
installation guide.

The [http://www.tele.ucl.ac.be/PEOPLE/DOUXCHAMPS/ieee1394/cameras/] IEEE1394
Digital Camera List, by Damien Douxchamps, offers an outstanding summary of
the capabilities of IEEE 1394 cameras as well as the current status of
support for individual models.
-----------------------------------------------------------------------------

2.3. Generic Parallel Port Support for Parport Webcams

For 2.2 and 2.4 kernel systems, parallel-port support must be enabled
statically or as a module (stock kernels usually have this enabled by
default). You may want to read [http://www.torque.net/linux-pp.html] more
generic info about parallel-port device support under the Linux kernel before
starting this process. To find out for sure if the module parport is loaded,
you can check the dmesg file or use lsmod as outlined above. Using dmesg |
less, you should see (among many other lines) the following:

+------------------------------------------------------------------------------------------------+
|                Mar  3 08:00:25 K7 kernel: parport0: PC-style at 0x378 (0x778) [PCSPP,TRISTATE] |
|                Mar  3 08:00:25 K7 kernel: parport0: irq 7 detected                             |
|                                                                                                |
+------------------------------------------------------------------------------------------------+

If you are compiling your own kernel, enable 'Parallel Port support'. You
should enable 'IEEE 1284 transfer modes', and if you have x86 type
architecture, you should also enable 'PC-style hardware'.

If modprobe returns an error when you attempt to load the module, note that
you may need to determine and supply the hardware address when invoking 
modprobe. The most common address is 0x378 for an x86 system; 0x278 and 0x3BC
are other possibilities for integrated or ISA parallel ports. Add-in PCI
parallel ports may have unusual base addresses. You can also arrange multiple
devices with either the parport_pc or parport_arc modules, though that topic
is beyond the scope of this document. WARNING: Be sure you have the correct
address before entering this information at the command line or else your
machine may become unstable, crash or otherwise implode.

Your parallel port should be set to preferably "EPP" mode, or alternatively
ECP/EPP. "Bidirectional" (also known as "BPP" or "PS/2") may work, albeit
much more slowly. "Unidirectional" mode is unsuitable for scanning. The above
setting can usually be accessed through your BIOS menu, at least on x86
systems.
-----------------------------------------------------------------------------

3. Making and Accessing the Video Device

3.1. Device Filesystem

[http://www.atnf.csiro.au/~rgooch/linux/docs/devfs.html]  Devfs, or 'device
filesystem', has been an option in the Linux kernel since the late 2.2
series. If you haven't used it up to this point, then I would suggest you at
least consider it. It can immensely simplify device management. Devfsd, the
device filesystem daemon, creates and removes devices on your system
dynamically without the need for user input. You can tell if your system is
running devfsd if you run ls -f /dev/ at the command line or in an xterm, and
see mostly symlinks pointing to a device file, or "node" within a logically
ordered hierarchy of subdirectories within /dev. You can also see devfsd
running when you check running programs with ps -A at the command line. The
daemon consumes very little memory. If you are running devfsd/devfs, you can
probably skip the following sections as the archaic process of creating
device nodes will be done for you, and it's simply a matter of finding the
device by selecting the appropriate symlink in /dev.

If you want to give devfs a try, you need to enable '/dev file system' and
'Automatically mount at boot' in the 'File Systems' section of kernel
configuration. Yes, it absolutely requires a recompile of your kernel if you
don't have it in there already. WARNING: The only other supporting package
required is 'devfsd', which you can obtain from your distribution vendor. 
WARNING: If you enable devicefs to automatically mount at boot-time without
installing the devfs daemon, you will be left with an unbootable system!

Devfs does not obviate the need to change permissions of devices for access
by users.

Naturally, the above comments about devfs are the opinion of your humble
author (among others) and should be treated as just that, especially if you
are a relative newbie or are not quite ready to compile your own kernel.

Beginning in the 2.6 series kernel devfs has been deprecated in favor of a
userspace (i.e., non-kernel) daemon known as udev, though devfs remains as an
option. You can find information on udev [http://www.kernel.org/pub/linux/
utils/kernel/hotplug/udev-FAQ] here if you are inclined to live on the
bleeding edge.
-----------------------------------------------------------------------------

3.2. Creating Video Devices Manually

If you aren't running devfs and devfsd, this is how it will need to be done,
unless you are using libusb or udev in which case you can skip this step. A
device can be created as a block (such as a drive), a fifo (file-in-file-out
or pipe, as in xconsole) or a character device, which represents other
hardware. Each device has a major and a minor number "coordinate" to tell the
kernel what it is and where to access it. These numbers are not arbitrary.

Video4linux device nodes are used to access video devices (including webcams)
and have the major number 81 and minor number 0, 1, 2, etc... First, check /
dev to see what directory your distribution lays out its video devices in.
Some distributions might have the video device(s) in the root /dev directory,
such as /dev/video0, /dev/video1...and so on. Others might place them within
/dev/v4l or in /dev/video. If you find that the video devices are already
present (made by your distributor or devfsd) then your work is done except
for possibly permissions. If not, you will need to create the device nodes
yourself. You can use the following script, which I have borrowed from the
kernel source (located in linux/Documentation/video4linux/bttv/MAKEDEV of the
source tree):

+---------------------------------------------------------------------------+
|                #!/bin/bash                                                |
|                                                                           |
|                function makedev () {                                      |
|                                                                           |
|                        for dev in 0 1 2 3; do                             |
|                        echo "/dev/$1$dev: char 81 $[ $2 + $dev ]"         |
|                        rm -f /dev/$1$dev                                  |
|                        mknod /dev/$1$dev c 81 $[ $2 + $dev ]              |
|                        chmod 666 /dev/$1$dev                              |
|                done                                                       |
|                                                                           |
|                # symlink for default device                               |
|                        rm -f /dev/$1                                      |
|                        ln -s /dev/${1}0 /dev/$1                           |
|                }                                                          |
|                                                                           |
|                # see http://roadrunner.swansea.uk.linux.org/v4lapi.shtml  |
|                        echo "*** new device names ***"                    |
|                        makedev video 0                                    |
|                        makedev radio 64                                   |
|                        makedev vtx 192                                    |
|                        makedev vbi 224                                    |
|                # "*** old device names (for compatibility only) ***"      |
|                #makedev bttv 0                                            |
|                #makedev bttv-fm 64                                        |
|                #makedev bttv-vbi 224                                      |
|                                                                           |
+---------------------------------------------------------------------------+

Simply copy and paste the above into your favorite editing program, save it
as MAKEDEV or whatever name you like and then make it executable (i.e., chmod
u+x MAKEDEV). Next, execute it as root:

 
+---------------------------------------------------------------------------+
|                # ./MAKEDEV                                                |
|                                                                           |
+---------------------------------------------------------------------------+
-----------------------------------------------------------------------------

3.3. Groups and Permissions

It is a good idea to be sure that your user account can access the device
once all modules are loaded and device nodes created. The most
security-conscious way to do that is to add access for a particular group. On
my system, the members of the group 'video' are allowed to use the webcam,
scanner and other photographic devices. The way to accomplish this is to
first change the ownership of the devices in /dev like so (as root):

+---------------------------------------------------------------------------+
|                # chown root.video /dev/usb/video1*                        |
|                                                                           |
|                                                                           |
+---------------------------------------------------------------------------+

...where root.video are the owner and group the device will now belong to.
Obviously, the specific command will vary by your system and the type of
device. It is important that you change the ownership of the device node
itself and not the symlink; symlinks' ownerships are affected only by
changing the parent devices or files they point to.

To see if your user account is a member of the group in question, as root
issue the following command: grep -e video /etc/group. You should see
something like the following:

+---------------------------------------------------------------------------+
|                video:x:44:                                                |
|                                                                           |
+---------------------------------------------------------------------------+

...where '44' is the group number. Since no members follow the last colon in
the 'video' group, we can add them, let's say user 'jhs' with the command

+---------------------------------------------------------------------------+
|                # adduser jhs  video                                       |
|                                                                           |
+---------------------------------------------------------------------------+

After this, it's simply a matter of allowing read and write access for the
user in question of the device like so:

+---------------------------------------------------------------------------+
|                # chmod g+rw /dev/v4l/video0                               |
|                                                                           |
+---------------------------------------------------------------------------+

...where g+rw means add read and write access for group. See the
documentation for chmod (man chmod or info chmod) for further info.
-----------------------------------------------------------------------------

4. Specific Webcam Models

Note that this information is frequently changing. The [http://http://
www.qbik.ch/usb/devices/index.php] Linux-USB Device Overview site is a great
place to look if you have a USB webcam. Also, you will want to check for your
model's homepage at [http://www.exploits.org/v4l/] http://www.exploits.org/
v4l/. The information compiled below on specific webcam models is from the
same source, so you may find more up-to-date information through the previous
link. If you can't find an entry for your particular hardware, you can find
links to resources on how to write your own driver!

It is important to note that if your camera isn't listed, the easiest way to
find out if your camera is supported is to find out what chipset is used in
its manufacture. This information is usually present in the specifications
published in your webcam's manual or on the manufacturer's website.

If you can't find your camera model listed and aren't sure what chipset your
camera is made with, you should consider searching and/or subscribing to
[https://listman.redhat.com/mailman/listinfo/video4linux-list] the
video4linux-list mailing list hosted by Redhat.
-----------------------------------------------------------------------------

4.1. 3com HomeConnect PC Digital Webcam

This driver is supported with the kernel patch located at [http://
homeconnectusb.sourceforge.net/] the homeconnectusb project web page. It may
require a kernel recompile after patching depending on your kernel version.
-----------------------------------------------------------------------------

4.2. CPiA based Webcams

Please see the [http://webcam.sourceforge.net/] project home page for
up-to-date information. This chipset has been used in the manufacture of both
USB and parallel port webcams including the following:

*Aiptek HyperVcam Fun USB (non-OV511 based)
   
*Creative Video Blaster WebCam II USB and parallel-port
   
*CVideo-Mail Express parallel-port
   
*Digicom Galileo USB and Digicom Galileo Plus
   
*Dynalink Digital Camera
   
*Ezonics EZCam (not Pro or Plus)
   
*I-View NetView NV200M
   
*Microtek EyeStar USB
   
*Pace Color Video Camera USB
   
*SuperCam WonderEye
   
*TCE Netcam 310 USB
   
*Terracam USB (non-OV511 based or Terracam Pro)
   
*Trust SpaceC@m Lite USB and SpaceC@m 100
   
*Utopia USB Camera
   
*ZoomCam USB and parallel-port
   

-----------------------------------------------------------------------------
4.3. SE401, SE402 and EP800 based USB webcams

This project is a work in progress. The drivers and other useful information
are available at the project homepage located[http://
members.brabant.chello.nl/~j.vreeken/se401] here. As of writing this, it is
necessary to patch and recompile your kernel in order to obtain support for
these models. The driver supports the following:

SE401 chipset via the 'se401' driver:

*Aox SE401 camera
   
*Philips PCVC665 USB VGA webcam 'Vesta Fun'
   
*Kensington VideoCAM PC Camera (Models 67014-67017)
   

SE402 and EP 800 chipsets via the 'epcam' driver

*Spypen Actor
   
*Rimax Slim Multicam
   
*Concord Eye-Q Easy
   
*Creative PD1001
   
*Chicony DC-100
   
*Endpoints SE402 and EP800
   

-----------------------------------------------------------------------------
4.4. OmniVision based Webcams

This category includes a multitude of webcam and video-capture devices
manufactured by Omnivision, including the OV511(+), OV518(+), OV6620, OV6630,
OV7610, and OV7620AE. The project homepage is [http://alpha.dyndns.org/ov511]
here. Supported models include:

*Aiptek HyperVcam Home and Mobile
   
*Amitech AWK-300
   
*I-view NetView NV300M
   
*TEVion MD9308
   
*Intel Me2Cam
   
*Dlink DSB C100, C300
   
*Hawking Tech. UC-110, UC-300 and UC-310
   
*Puretek PT-6007
   
*Alpha Vision Tech AlphaCam SE model AC-520
   
*Creative Labs WebCam model PD1001 with OV518 chipset
   
*Creative Labs WebCam 3, WebCam Go, Webcam Go Plus
   
*Elecom UCAM-C1C20
   
*Elta WEBCam 8211 PCC
   
*Ezonics EZPhone Cam
   
*Philips ToUCam XS (old version with OV518)
   
*LG Electronics LPC-UM10
   
*Lifeview various USB Life TV models
   
*Genius VideoCam Express
   
*AverMedia Intercam Elite
   
*Maxxtro Cam22U
   
*MediaForte MV300, PC Vision 300
   
*Terratec TerraCam PRO and some TerraCam models
   
*OmniVision (except those with OV519)
   
*TRENDNet TV-PC301
   
*Trust Sp@ceC@m USB
   
*Lifetec LT9388
   
*BestBuy EasyCam U
   
*Maxell Maxcam
   
*TCE NetCam 310u
   
*Medion MD9388
   
*Webeye 2000B
   
*Suma eON
   
*Prochips PCA-3100
   
*Ezonics EZ USB Cam II (the OV511+ models)
   
*Waytech I-Pac VIC-30
   
*Zoom Telephonics ZoomCam III USB (model 1598)
   

-----------------------------------------------------------------------------
4.5. Logitech (formerly Connectix) Quickcam Support

The QuickCam VC USB and parallel port model webcams are supported by the
driver offered [ http://digilander.libero.it/demarchidaniele/qcamvc/
quickcam-vc.html] here. A kernel patch and recompile are necessary for
support of this model.

The Quickcam Express Linux project offers two different flavors of driver for
certain Quickcam models, both of which are stand-alone drivers that do not
require a kernel patch or recompile. The [http://qce-ga.sourceforge.net/]
qce-ga and [http://www.ee.oulu.fi/~tuukkat/quickcam/quickcam.html] qc-usb
drivers support the following models:

*Logitech Quickcam Express
   
*Quickcam Web
   
*Legocam
   
*Dexxa Webcam
   
*Labtec Webcam
   

 

The qc-usb driver is more experimental but reportedly works better on some
models such as the Quickcam Web. See the above links for more information.
Note to Redhat users: The qce-ga driver doesn't compile properly using the
modified kernel source provided in Redhat 9, but a fix is available [http://
www.ee.oulu.fi/~tuukkat/quickcam/FAQ] here.

Some Logitech camera models are supported by the Philips driver in Section
4.7.
-----------------------------------------------------------------------------

4.6. NW802 Based Webcams

This chipset, manufactured by DIVIO, is supported by the driver found [http:/
/nw802.sourceforge.net] here. The models supported include the following:

*BTC SurfCam CMOS300k
   
*Mustek WCam 300
   
*Logitech QuickCam Pro USB (the earlier "dark focus ring" model)
   

-----------------------------------------------------------------------------
4.7. Philips USB Webcams

Supported Philips models include the following. The up-to date PWC driver and
list can be found at [http://www.smcc.demon.nl/webcam/release.html#pwc] the
project homepage.

*PCA645VC
   
*PCA646VC
   
*PCVC675K Vesta, Vesta Pro and Vesta Scan
   
*PCVC720K/40 ToUCam XS, ToUCam Fun, ToUCam Pro and ToUCam Scan
   
*Askey VC010
   
*Creative Labs Webcam 5, Pro Ex
   
*Logitech 3000 and 4000 Pro, Notebook Pro, and Zoom
   
*Samsung MPC-C10 and MPC-C30
   
*Sotec Afina Eye
   
*Visionite VCS UM100 and UC300
   

-----------------------------------------------------------------------------
4.8. STV0680 based Models

The USB version of webcams made with this chipset are supported by the 2.4.18
and above kernel with the stv680.o module. Alternatively, you can obtain the
source from [http://stv0680-usb.sourceforge.net] the project homepage. This
driver supports models including the Aiptek Pencam and the Nisis Quickpix 2.

If you have a serial version, the main one of which is the Scan e-Studio, you
should go [http://stv0680.sourceforge.net] here.
-----------------------------------------------------------------------------

4.9. Winbond w9966cf

This is a driver for the parallel-port interface that supports the Philips
SAA7111 CCD-control chip as found on the Lifeview Flycam SUPRA webcam. It is
included in the late 2.4 kernel series and later under the heading
'video4linux' support. The homepage for this project is [http://
hem.fyristorg.com/mogul/w9966.html] here. 
-----------------------------------------------------------------------------

4.10. Xirlink C-it?? HDCS-1000 based Webcams

This driver is for the USB webcams manufactured by Xirlink, IBM (PC Camera)
and Veo Stingray model webcams. Support has been in the linux kernel USB
section since 2.2.12. The homepage is at [http://www.linux-usb.org/ibmcam]
http://www.linux-usb.org/ibmcam.
-----------------------------------------------------------------------------

5. Framegrabbing Applications

-----------------------------------------------------------------------------
5.1. Xawtv

Xawtv is a suite of tools available for accessing video devices in linux, the
workhorse of which is the Xawtv program itself. The home page is at [http://
bytesex.org/xawtv] http://bytesex.org/xawtv. You'll probably want to install
an already packaged rpm, tgz or deb of xawtv; though, courageous or curious
types can always get the latest source from the previous link.

When you first try out your webcam, and you think things are configured
right, use the -hwscan option:

+------------------------------------------------------------------------------------+
|                $ xawtv -hwscan                                                     |
|                This is xawtv-3.72, running on Linux/i686 (2.4.21)                  |
|                looking for available devices                                       |
|                                                                                    |
|                /dev/v4l/video0: OK                     [ -device /dev/v4l/video0 ] |
|                type : v4l                                                          |
|                name : BT878(Hauppauge (bt878))                                     |
|                flags: overlay capture tuner                                        |
|                                                                                    |
|                /dev/v4l/video1: OK                     [ -device /dev/v4l/video1 ] |
|                type : v4l                                                          |
|                name : IBM USB Camera                                               |
|                flags:  capture                                                     |
|                                                                                    |
+------------------------------------------------------------------------------------+

...so now you can see the available devices (your output may differ
substantially). Try opening an xterm and running xawtv, grabbing from your
webcam video device:

+---------------------------------------------------------------------------+
|                $ xawtv -c /dev/video1                                     |
|                This is xawtv-3.72, running on Linux/i686 (2.4.21)         |
|                                                                           |
+---------------------------------------------------------------------------+

...and (hopefully) your camera will begin capturing to a window on your
desktop. You may see some error messages in your xterm if things don't work
that can be helpful to diagnose configuration problems. If you aren't
interested in all that, and things work for you, launch from your window
manager's menu next time. You can read about more xawtv options with man
xawtv.
-----------------------------------------------------------------------------

5.2. MoTV

MoTV is a rewrite of Xawtv using the Motif toolkit, and as such functions
similarly to Xawtv. It looks more polished but otherwise differs very little
from Xawtv. You can get it from the Xawtv home page.
-----------------------------------------------------------------------------

5.3. Streamer

Streamer is a versatile program that allows a capture from a webcam or video
device using only the command line. It may be in your Xawtv package already
(or may need to be fetched separately as in Debian), and is available at the
Xawtv homepage referenced in Section 5.1. It is a great program for
automating camera functions. For example, to take a standard JPEG picture
from the command line where the camera is accessed through /dev/video1:

+---------------------------------------------------------------------------+
|                $ streamer -c /dev/video1 -b 16 -o outfile.jpeg            |
|                                                                           |
+---------------------------------------------------------------------------+

...where -b is the number of colors (in bpp, whether 15, 16, 24 or 32) and -o
is the output filename that will be dropped into the current directory
(specify -o /path/outfile.jpg to place it elsewhere).

To make an .avi file:

+------------------------------------------------------------------------------------------------+
|                $ streamer -q -c /dev/video1 -f rgb24 -r 3 -t 00:30:00 -o /home/jhs/outfile.avi |
|                                                                                                |
+------------------------------------------------------------------------------------------------+

...where -q is for 'quiet' execution (no message output), -f is 'format'
(rgb24 is TrueColor avi), -r is the frames per second and -t is the time of
recording (30 minutes). Streamer can capture raw and Quicktime??
(non-Sorensen) formats and can capture audio as well. See streamer --help for
more information.
-----------------------------------------------------------------------------

5.4. Motion

Motion is a brilliant program that is able to monitor the video signal from
one or several webcams. It can record periodic snapshots, and when motion is
detected, record an mpeg and/or perform another action such as sending an
email or executing a command. It can track and graphically mark the motion it
detects, feed files via an http server to your website, stream them to
another application and more. It is accessed through the command line and the
number of options may be intimidating; there is however, a [http://
www.lavrsen.dk/sources/webcam/motion_guide.htm] guide available online that
outlines the various command and configuration file options nicely. The
motion homepage can be found at [http://motion.sourceforge.net] http://
motion.sourceforge.net.
-----------------------------------------------------------------------------

5.5. Gqcam

[http://cse.unl.edu/~cluening/gqcam/] Gqcam is a graphical GTK+-based
application originally written to access Connectix QuickCams but now supports
nearly all Video4Linux compatible webcam devices. It has an intuitive
interface that makes viewing, taking snapshots, and configuring webcam
settings blissfully easy. It is highly recommended for newbies and those who
only want to look at the camera and take a picture here and there without
editing a configuration file or using the command line.
-----------------------------------------------------------------------------

5.6. camE

CamE is a command-line program that works in daemon mode to capture frames
from your v4l device for archive or upload (to a webserver, for example) via
ftp or scp. You can overlay other graphics, timestamp the frames, or add
other dynamic text all by altering the appropriate line in the configuration
file. See [http://linuxbrit.co.uk/camE/] the camE homepage for more
information.
-----------------------------------------------------------------------------

5.7. SANE

SANE, or Scanner Access Now Easy, supports access of cameras including
webcams in later versions. If you are familiar with using a photographic
scanner device in Linux, you may be interested in using SANE for image
capture, especially since a few devices double as both scanners and digital
cameras. See the relevant sections of the Scanner-HOWTO [http://tldp.org/
HOWTO/Scanner-HOWTO/sane.html#getting-SANE] here.
-----------------------------------------------------------------------------

6. Troubleshooting

6.1. Help, How do I figure out what my USB camera chipset is if the model
isn't listed in your HOWTO?

If you have a usb camera (and /proc filesystem support and usb-filesystem
support), issue the following at the command line:

+---------------------------------------------------------------------------+
|                $ cat /proc/bus/usb/devices                                |
|                                                                           |
+---------------------------------------------------------------------------+

You should receive output including (but not necessarily limited to) the
following:

+----------------------------------------------------------------------------------+
|                T:  Bus=01 Lev=01 Prnt=01 Port=01 Cnt=01 Dev#=  3 Spd=12  MxCh= 0 |
|                D:  Ver= 1.01 Cls=ff(vend.) Sub=ff Prot=ff MxPS= 8 #Cfgs=  1      |
|                P:  Vendor=0545 ProdID=8080 Rev= 3.0a                             |
|                S:  Product=USB IMAGING DEVICE                                    |
|                                                                                  |
+----------------------------------------------------------------------------------+

The line beginning "T:" is the USB bus the device is attached to. The "P:"
indicates (obviously) the vendor and product ID, which are catalogued at the
[http://www.linux-usb.org] linux USB Project homepage.
-----------------------------------------------------------------------------

6.2. Help, I can't find the camera device in /dev!

Assuming your connection type is supported, and your camera is working, see 
Section 3.2.
-----------------------------------------------------------------------------

6.3. Help, I can see the camera device, but I can't access it!

See Section 3.3.
-----------------------------------------------------------------------------

6.4. Help, my camera has a driver that is source-only, i.e., has to be built
by me! Where do I start?

First, check if your Linux distribution offers a pre-compiled binary of the
driver. If that is not the case, be sure you have kernel sources installed.
You will also need at a minimum GNU make, gcc, binutils and perhaps other
programs installed depending on your distribution. Download the driver source
(in this example named src.tar.gz) and uncompress/untar it:

+---------------------------------------------------------------------------+
|                $ tar -xvzf src.tar.gz                                     |
|                                                                           |
+---------------------------------------------------------------------------+
Then, change to the directory of your kernel source:
+---------------------------------------------------------------------------+
|                # cd /usr/src/linux                                        |
|                                                                           |
+---------------------------------------------------------------------------+
Make the necessary source files:
+---------------------------------------------------------------------------+
|                # make oldconfig                                           |
|                # make dep                                                 |
|                                                                           |
+---------------------------------------------------------------------------+
Now, change to the directory where you unpacked the driver source and read
the README and/or INSTALL files for instructions on how to make the driver.
Usually this involves some combination of "make" "make all" and/or "make
install." Assuming it compiles correctly, you can simply load the new module
with modprobe. If you have any problems, see Section 6.6.
-----------------------------------------------------------------------------

6.5. Help, my camera is supported by a driver that has to be patched into my
kernel! What do I do?

 See [http://tldp.org/HOWTO/Kernel-HOWTO/patching_the_kernel.html] the
section on patching of the Kernel-HOWTO at [http://tldp.org] The Linux
Documentation Project.

The short and unguaranteed version of patching, by your humble author, goes
as follows: Be sure you have the same prerequisites outlined in Section 6.4
installed. First, on the command line or in an xterm change to the source
directory of the kernel version you are (or will be) running with the camera
patch (in this example named patch.diff).

+---------------------------------------------------------------------------+
|                # cd /usr/src/linux                                        |
|                # patch -p1 -E patch.diff                                  |
|                                                                           |
|                                                                           |
+---------------------------------------------------------------------------+

You should see a confirmation that the 'hunks' were successfully applied. At
this point, you can make menuconfig or whatever program you use to recompile,
enabling the appropriate support. If any of the hunks failed, or you run into
any problems in addition to the link referenced above you, should consult man
patch and Section 6.6.
-----------------------------------------------------------------------------

6.6. Help--as in, where can I get more of it?

See the video4linux mailing list headquarters at [https://listman.redhat.com/
mailman/listinfo/video4linux-list] https://listman.redhat.com/mailman/
listinfo/video4linux-list.
-----------------------------------------------------------------------------

6.7. Help, I want to contribute to Video4Linux support in Linux! Who do I get
in touch with?

See [http://www.thedirks.org/v4l2/peopleprojects.htm] this page.
-----------------------------------------------------------------------------

A. Gnu Free Documentation License

Version 1.2, November 2002

Copyright (C) 2000,2001,2002 Free Software Foundation, Inc. 59 Temple Place,
Suite 330, Boston, MA 02111-1307 USA Everyone is permitted to copy and
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just after the title page:

Copyright (c) YEAR YOUR NAME. Permission is granted to copy, distribute, and/
or modify this document under the terms of the GNU Free Documentation
License, Version 1.2 or any later version published by the Free Software
Foundation; with no Invariant Sections, no Front-Cover Texts, and no
Back-Cover Texts. A copy of the license is included in the section entitled
"GNU Free Documentation License".

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts,
replace the "with...Texts." line with this: with the Invariant Sections being
LIST THEIR TITLES, with the Front-Cover Texts being LIST, and with the
Back-Cover Texts being LIST. If you have Invariant Sections without Cover
Texts, or some other combination of the three, merge those two alternatives
to suit the situation.

If your document contains nontrivial examples of program code, we recommend
releasing these examples in parallel under your choice of free software
license, such as the GNU General Public License, to permit their use in free
software.
