Jusfixit at 14:44, 19 August 2010

2010-08-19T14:44:59Z

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Here are some initial clues toward making a Logitech Webcam Pro 9000
camera co-operate with Zoneminder. On the Zoneminder console:
http://localhost/zm/index.php
when one selects the "Add New Monitor" command button, some appropriate
values may resemble:

General tab
Name Whose_webcam
Source Type Local
:
Source tab
Device Path /dev/video0
Capture Method Video For Linux version 2
Device Channel 0
Device Format PAL B
Capture Palette YUYV
Capture Width (pixels) 1600
Capture Height (pixels) 1200

One clue for the correct value to supply for the Device Path is to scan (as the root user) through the entries in the /dev directory for an entry created at the time the webcam was first connected to this computer system.

/dev:
crw-rw----+ 1 root video 81, 0 Aug 16 19:20 video0

If Zoneminder drops FATAL error messages in e.g. /var/log/messages such as:

zmc ... [Failed to stat video device /dev/video: No such file or directory]

the guess for the Device Path was incorrect or entered with a typographical error.

More clues for the correct values to supply for the Device Format and Capture Palette may be found using the zmu utility program which is included with your Zoneminder installation:

[root@who ~]# zmu -d /dev/video0 --query
error22
[root@who ~]# zmu -d /dev/video0 -V2 --query
error22
[root@who ~]# zmu -d /dev/video0 -V1 --query
d:/dev/video0|N:UVC Camera (046d:0809)|T:1|nC:1|nA:0|mxW:1600|mxH:1200|mnW:48|mnH:32|X:0|Y:0|W:640|H:480|P:8|D:16|B:32896|h:0|Cl:7196|Cn:8224|w:0|n0:Camera 1|C0:0|Fl0:0|T0:2|F0:0
[root@who ~]# zmu -d /dev/video0 --verbose -V1 --query
Video Device: /dev/video0
Video Capabilities
Name: UVC Camera (046d:0809)
Type: 1
Can capture
Video Channels: 1
Audio Channels: 0
Maximum Width: 1600
Maximum Height: 1200
Minimum Width: 48
Minimum Height: 32
Window Attributes
X Offset: 0
Y Offset: 0
Width: 640
Height: 480
Picture Attributes
Palette: 8 - YUYV
Colour Depth: 16
Brightness: 32896
Hue: 0
Colour :7196
Contrast: 8224
Whiteness: 0
Channel 0 Attributes
Name: Camera 1
Channel: 0
Flags: 0
Type: 2 - Camera
Format: 0 - PAL
[root@who ~]#

I have not found a combination of values using Capture Method "Video for Linux version 1" that works with this camera. Some forum postings point toward imperfections in zmu, and other Logitech cameras that need Device Format "PAL B", which is only available under "Video for Linux version 2". Thus far, I have only used one value for the Capture Width (1600) and the Capture Height (1200), but there are many other image sizes that this camera may supply. See:

http://www.quickcamteam.net/devices/logitech_uvc_frame_format_list.pdf

pages 5 and 6 (of 19) lists the ~18 frame formats for motion JPEG and the ~18 frame formats for still images. (No, I do not understand why each resolution and frame rate is listed twice in each list.)

If you are wishing to use a higher-resolution choice from this list, or you are seeing ERROR messages such as:

zm ... [Can't shmget, probably not enough shared memory space free: Invalid argument]

in the logs, you want to read and implement the instructions near:

http://www.zoneminder.com/wiki/index.php/FAQ#What_does_a_.27Can.27t_shmget:_Invalid_argument.27_error_in_my_logs_mean.3F_and_my_cameras_won.27t_display_video_at_higher_resolutions

If you see FATAL messages such as:

zmc... [Failed to setup memory: Invalid argument]

you did not select the correct Device Format.

Following through this chain of references:

http://www.quickcamteam.net/documentation/reference
http://www.usb.org/developers/devclass_docs
http://www.usb.org/developers/devclass_docs/USB_Video_Class_1_1.zip

can lead one to documentation for "USB Video Class 1.1", the current version of the UVC specification.

Logitech Webcam Pro 9000 - Revision history

Jusfixit at 14:44, 19 August 2010