Provided by: vgrabbj_0.9.9-3_amd64 bug


       vgrabbj - grab images from a v4l-compatible webcam


       vgrabbj [options]


       This manual page documents briefly the vgrabbj command.

       vgrabbj  is a program that will grab images from any v4l-capable device which supports one
       of the rgb24, rgb32, yuv420, yuv420p, yuyv, uyvy, or yuv422 palettes and saves  the  image
       as a .jpg, .png, or .pnm file.

       Optional,  it  can  timestamp  the  resulting  image,  and/or  upload  it to a ftp-server.
       Additionally, a daemon-mode is available to do the above regularly.

       On startup, the default configuration file /etc/vgrabbj.conf is read and evaluated.  If  a
       configuration  file  is  specified via the -c parameter (see below), that file is read and
       parsed. Values which are present in the default config file keep their  values.   Finally,
       the  commandline  is  evaluated. If an option is presented more than once, the last in the
       commandline is taken.  If no options given, vgrabbj tries to open the  default  v4l-device
       /dev/video0, grab an image and return it on /dev/stdout.  So be aware.


       All  options  are  either  numeric values, strings, or booleans. If it is a boolean switch
       (e.g. no value/string shown after the switch), it plainly switches the current setting  of
       that  particular option.  Remember, vgrabbj.conf is read first, so any option set to on or
       off there will be toggled by the commandline switch.

       -h     Show summary of options and version number.  -c <filename>  Specifies  filename  as
              alternative configuration file.

       -l <seconds>
              Daemonize & loop with seconds intervals (min. 1).

       -L <microseconds>
              Daemonize & loop microseconds intervals (min. 1). Same as -l except you can control
              it more precisely.

       -a     Enable vgrabbj's  brightness  adjustment  (default:  disabled).  To  use  vgrabbj's
              brightness  adjustment,  RGB24  support of the device is necessary. You may have to
              provide it to your device via the -F parameter (see below).  If  your  device  does
              not support RGB24, this setting is silently ignored.

       -q <quality>
              Sets the quality of a jpeg output to quality (1-100, default: 75).

       -i <imagesize>
              Sets the imagesize of input device, where imagesize is one of:

               sqcif= 128x96,     qsif = 160x120,
               qcif = 176x144,    sif  = 320x240,
               cif  = 352x288,    vga  = 640x480,
               svga = 800x600,    xga  = 1024x768,
               sxga = 1280x1024,  uxga = 1600x1200,

              (default: cif)

       -w <width>
              Sets  the width of the image to width. Needs -H.  The v4l-device has to support the
              image width you set with this option.

       -H <height>
              Sets the height of the image to height. Needs -w.  The v4l-device  has  to  support
              the image height you set with this option.

       -o <format>
              Sets the output to format (either jpeg, png, or pnm, default: jpeg)

       -f <filename>
              Output is written to filename (default: /dev/stdout)

       -A <path+filename>
              Additional  to the output of -f another file is written to the named path+filename,
              whereas the whole may be formatted  according  to  strftime(2).  This  enables  the
              creation  of  an  archive of images. Currently, the output is only supported on the
              same filesystem as the original output.

       -E <value>
              Defines how many images shall be read until a copy for the archive is made. E.g.  1
              means  each image taken is also put in the archive.  5 would mean every fifth image
              taken is put in the archive.

       -M <value>
              Sets the maximum number of images kept in the archive. If you defined 5 seconds for
              daemon  mode, archive every image, you collect 720 images per hour. If you set this
              switch to 720 you would keep an hour of images in the archive.

       -d <device>
              Sets the input device to device (default: /dev/video0)

       -s <device>
              This flag causes vgrabbj to print the v4l capabilities of <device> and exit.

       -C     Causes vgrabbj to open the device only  while  image  data  is  grabbed.   This  is
              helpful  if  you need access to the device besides vgrabbj. It's use is discouraged
              due to possible problems with memory fragmentation.  Default is to  keep  the  v4l-
              device open while vgrabbj is running.

       -g     Disables  setting of the image size (see -i, -H, and -w. Necessary for certain v4l-
              devices which do not support to be set to a particular image  size  (e.g.  IBM-usb-
              cam, QuickCam). For these devices you have to specify the size at module load time.

       -S     Switches colormap from BGR to RGB (or vice versa). Use if you have odd colors.

       -R     Swaps left and right of the image like a mirror.

       -U     Swaps  top  and  bottom of the image like a mirror (e.g. for upside-down montage of
              the cam).

       -G     Turns off use of mmap'ed memory. see vgrabbj.conf(5) for details.

       -D <value>
              Sets the loglevel of vgrabbj. Valid for value are 0, 2, 3, 4, 6, 7 (default: 4).  0
              means  no  messages  at  all, 7 is debug. Don't use 7 if you are running vgrabbj in
              daemon mode, it'll surely fill your syslog. Be aware, that  loglevel  7  will  also
              write your ftp-password (if defined in vgrabbj.conf(5)) in the logfile!

       -n     Disable  the  use of the temporary outputfile and write directly to the output-file
              specified with -f. Output to /dev/stdout is always written directly without the use
              of a temporary file.

              If  a  filename different from /dev/stdout was given with the -f parameter, vgrabbj
              defaults to use a temporary file called filename.tmp to write the image. This  file
              is  then  renamed  to  filename to shorten the time period corrupt data may be read
              from filename.

       -Z 'commands'
              Ask vgrabbj to launch an external program. May be used to pass the picture  through
              ImageMagick  or others filters. The first '%s' instance in the command line will be
              replaced with filename. If UseTmpOut is On, 'commands' will be run before the  file
              is renamed.

       -F <palette>
              Force  the  usage  of  the specified palette. If palette is not supported by either
              vgrabbj or the v4l-device, fallback to a palette supported by both is provided.  If
              no  common  denominator is available, vgrabbj exits. See DESCRIPTION for details on
              palettes supported by vgrabbj. Possible values are (copy from videodev.h):

               1  VIDEO_PALETTE_GREY      Linear greyscale
               2  VIDEO_PALETTE_HI240     High 240 cube (BT848)
               3  VIDEO_PALETTE_RGB565    565 16 bit RGB
               4  VIDEO_PALETTE_RGB24     24bit RGB
               5  VIDEO_PALETTE_RGB32     32bit RGB
               6  VIDEO_PALETTE_RGB555    555 15bit RGB
               7  VIDEO_PALETTE_YUV422    YUV422 capture
               8  VIDEO_PALETTE_YUYV
               9  VIDEO_PALETTE_UYVY
               10 VIDEO_PALETTE_YUV420
               10 VIDEO_PALETTE_YUV411    YUV411 capture
               11 VIDEO_PALETTE_RAW       RAW capture (BT848)
               12 VIDEO_PALETTE_YUV422P   YUV 4:2:2 Planar
               13 VIDEO_PALETTE_YUV411P   YUV 4:1:1 Planar
               14 VIDEO_PALETTE_YUV420P   YUV 4:2:0 Planar
               15 VIDEO_PALETTE_YUV410P   YUV 4:1:0 Planar
               16 VIDEO_PALETTE_PLANAR

              (no default, depends on v4l-device)

       -z <value>
              value images are grabbed and immediately discarded. Only the last image is  written
              to  the  output. This might be helpful if your v4l-device needs to take a couple of
              images to auto-adjust to the current light.

       -X     Does not fork daemon process and  keeps  vgrabbj  in  daemon  mode  in  foreground,
              attached  to  the  terminal.  Useful for debugging purpose. Not available in config


       With the following options you can control the hardware settings of your cam -  if  it  is
       supported  by your cam. Be aware that these options might break your hardware, as there is
       no check on what values are available, allowed, and supported by your hardware.

       -W <value>
              Whiteness definition.

       -r <value>
              Color definition.

       -x <value>
              Contrast definition.

       -b <value>
              Brightness definition.

       -u <value>
              Hue definition.


       The following options are available only if vgrabbj was compiled with the freetype library
       available.  If  you  set  any  one  of  these options on the commandline timestamp will be
       enabled with default values for all other options.

       -e     Switches timestamp to be used or not. Default is off,  but  may  be  overridden  by
              config-file,  so  just  try  to  enable this switch if there is no timestamp in the
              resulting image.

       -t <filename>
              The    TrueType    font    to    be    used    for    the    timestamp     (default

       -T <size>
              Set the fontsize to size for timestamp (3-100, default: 12).

       -p "<format-str>"
              Defines  the timestamp. format-str can be plain text or any strftime format and has
              to be enclosed with '""' (default: "%a, %e.  %B %Y -  %T"  -  see  strftime(3)  for

       -P <value>
              Alignment of the timestamp in the image. Possible value:

              0 = upper left,    1 = upper right,
              2 = lower left,    3 = lower right,
              4 = upper center,  5 = lower center

              (default: 1).

       -m <value>
              Defines the blend between font background and image (1-100, default: 60).

       -B <value>
              value  pixels  will  be used as border around the timestamp string (1-255, default:


       There are no options for ftp-upload on the command line.  This  is  due  to  the  need  to
       provide  a  password  which  would  be visible via the ps(1) command. See vgrabbj.conf for
       details on how to set-up the ftp-upload option.  Additionally, vgrabbj has to be  compiled
       with libftp support.


       %F  in  the archive time-string (year with century) causes memory corruption at a pentium-
       machine running vgrabbj (not validated). No further bugs are known at this time.


       vgrabbj.conf(4), strftime(3), ps(1)


       This manual page was originally written by Michael Janssen <>, for  the
       Debian GNU/Linux system and enhanced by Jens Gecius <>.

                                        February  24, 2002                             VGRABBJ(1)