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       vgrabbj.conf - configuration file for vgrabbj


       vgrabbj purpose is to read data from a v4l-device and put it in a file,
       formatted as jpeg, png, or pnm. Except for  the  ftp-options  described
       below  everything  can  also  handled  on  the  commandline.   Here the
       configuration statements are described.

       Syntax is <keyword> <value>. Comments start with a ';'  or  '#'.  Those
       lines  are  ignored  by vgrabbj. Case of the keywords and named options
       doesn't matter except for the timestamp option as well as any filename.

       The  configuration  file is parsed line by line. If any keyword appears
       twice or more often, the last one is the one used.

       On startup, the pre-defined  configuration  file  /etc/vgrabbj.conf  is
       read.  Then,  commandline parameters are evaluated one by one, the last
       is the most significant, if one option is provide twice or more  often.
       Same applies for the commandline parameter -c <config-file>.


       DaemonSeconds seconds
              Daemonize & loop with seconds intervals (min. 1).

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

       AutoBrightness On|Off
              Defines if vgrabbj's brightness adjustment is used. This  option
              works  only if the device supports data fetch via read and RGB24
              videopalette. See ForcePalette on how-to set RGB24. Some  device
              do not support RGB24, hence, Brightness is ignored.

       ImageQuality quality
              Sets  the  quality  of a jpeg output to quality (1-100, default:

       ImageSize 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)

       ImageWidth 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.

       ImageHeight 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.

       OutputFormat format
              Sets  the  output  to format (either jpeg, png, or pnm, default:
              jpeg). Alternative, you may provide jpg for jpeg.

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

       Archive <path/filename>
              Additional output is  written  to  path/filename  (default:  not
              set),   whereas  the  path-filename  can  include  any  strftime
              component. The  path-  filename  must  not  be  on  a  different
              filesystem  as the output defined above.  Additionally, you need
              to take care of the number of files stored. There  is  no  upper
              ceiling for archiving.

       VideoDevice <device>
              Sets the input device to device (default: /dev/video)

       OpenOnce On|Off
              Defines  if  vgrabbj  opens  the device only while image data is
              grabbed (Off) or keeps it  opened  while  it  is  running  (On).
              Setting  it  to  Off is helpful if you need access to the device
              besides vgrabbj. This use is discouraged though, due to possible
              problems with memory fragmentation. Default is On.

       SetImageSize On|Off
              Defines  if the image size (see -i, -H, and -w) of the device is
              set by vgrabbj. 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.  Default is On.

       SwitchColor On|Off
              Switches  colormap from BGR to RGB (or vice versa) if set to On.
              Default is Off. Use if you have odd colors.

       SwapRL On|Off
              Swaps left and right of the image like a mirror.  Default:  Off.
              is Off.

       SwapTB On|Off
              Swaps  top  and bottom of the image like a mirror. Default: Off.
              is Off.

       NoUseMmap On|Off
              Turns off the use of  mmap'ed  (better)  memory  allocation  for
              grabbing  frames.   Some  (very  rare)  cams  cannot use mmap'ed
              memory and have to use read. If you want to switch  easily,  use
              this  switch. If you don't know what I'm talking about, leafe it
              like it is: Default is Off.

       DebugLevel 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 post you
              ftp-password (if defined) in the logfile!

       UseTmpOut On|Off
              Sets the use of the temporary outputfile. Default is On. Ignored
              in case the default output (/dev/stdout) is used. If set to Off,
              the data is written directly to the file defined by  OutputFile.
              If   filename  is  different  from  /dev/stdout  (given  via  -f
              parameter or OutputFile, 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.

       ForcePalette 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. Supported palettes are marked  with
              * below. 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_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).

       DiscardFrames 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.


       The following options are useful if you want to keep a  certain  amount
       of  images  in  an archive. Currently, the archive is only supported if
       kept on the same filesystem as the images taken.

       Archive <archive-filename-pattern>
              The archive-filename-pattern is evaluated as a timestring, hence
              the   same   applies   as  to  TimeStamp  (see  below,  default:

       ArchiveEach <value>
              Defines how many images have to be taken before a copy  is  made
              for  the  archive.  E.g.  if defined 1, each image is put in the
              archive; if defined 5 every fifth image is put in the archive.

       ArchiveMax <value>
              Sets the maximum number of images to be put in the archive.


       The following options are available only if vgrabbj was  compiled  with
       the  freetype  library available. The timestamp will only be enabled if
       all values evaluated (inlcuding defaults) lead to a valid configuration
       and UseTimestamp is set to On.

       UseTimestamp On|Off
              This is the essential setting to enable timestamps if defined in
              the config file. Without this being set to  On,  it  just  won't
              work  (although,  if  there  are  options set to have an invalid
              configuration, it won't work either).  This is different to  the
              handling on the commandline.

       FontFile filename
              The  TrueType  font  to  be  used  for  the  timestamp  (default

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

       TimeStamp format-str
              Defines the timestamp. format-str  can  be  plain  text  or  any
              strftime  format.  Any  '""' at the beginning or the end will be
              eliminated  for  compatibility  reasons,  i.e.  they   are   not
              necessary  (default: "%a, %e.  %B %Y - %T" - see strftime(3) for

       Position value
              Alignment of the timestamp in the image. Possible value:

              ul = upper left,    ur = upper right,
              ll = lower left,    lr = lower right,
              uc = upper center,  lc = lower center

              (default: upper right). You can use either the short or the long

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

       BorderSize value
              value pixels will be used as border around the timestamp  string
              (1-255, default: 2).


       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)

       EnableFtp On|Off
              Ftp-Connection  will  only be opened if set to On. Be aware that
              this might bring up a dial-up connection.  See  also  KeepAlive.
              (default: Off)

       RemoteHost hostname
              Host  to which a ftp-connection will be established everytime an
              image  has  been  written  (see  also:  Daemon,   DaemonSeconds,
              KeepAlive, default: camimage.jpg).

       RemoteDir path
              The path consists of the full path on the remote host defined by
              RemoteHost (default: /).

       RemoteImageName filename
              The filename consists of the  full  path  and  filename  on  the
              remote host defined by RemoteHost (default:

       Username username
              The  name  of the user to log on the remote ftp-server (default:

       Password password
              The password of  the  user  to  log  on  the  remote  ftp-server
              (default:  bar). Be aware, that the password is kept unencrypted
              in memory, it might be read by others.

       KeepAlive On|Off
              If set to On, the connection will be kept.  This  will  cause  a
              dial-up line to be up all the time, which in turn may cost a lot
              of money! If set to Off,  the  connection  will  be  established
              after   an   image   was   written   to  the  OutputFile.  After
              transmission, the ftp-connection will be ended.  This  may  also
              result   in   phone   charges,   for   which   Author  takes  no
              responsibility. See License.

       Passive On|Off
              If set to On, passive ftp will be used. This can help connecting
              to ftp servers from the inside of a NAT-ed network.

       TryHarder On|Off
              Not implemented, yet.


       With  the following options you may alter the settings of your hardware
       (the cam), if supported by the cam. Be aware,  this  might  break  your
       hardware,  as  there  are  no  checks if the values supplied are valid,
       allowed, or supported!

       -W <value>
              Whiteness definition.

       -r <value>
              Color definition.

       -x <value>
              Contrast definition.

       -b <value>
              Brightness definition.

       -u <value>
              Hue definition.


       At my own machine running vgrabbj, the %F in a Archive-Filename  causes
       memory  corruption.   This  is  not  validated by any other machine. No
       further bugs are known at this time.


       vgrabbj(1), 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