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       fswebcam - Small and simple webcam for *nix.


       fswebcam [<options>] <filename> [[<options>] <filename> ... ]


       fswebcam  is  a  small  and  simple webcam app for *nix. It can capture
       images  from  a  number  of  different  sources  and   perform   simple
       manipulation  on  the  captured image. The image can be saved as one or
       more PNG or JPEG files.

       The PNG or JPEG image can be sent to stdio using the filename "-".  The
       output filename is formatted by strftime.


   Configuration File
       Config  files  use the long version of options without the "--" prefix.
       Comments start with a # symbol at the beginning of the line.

   General Options
       -?, --help
              Show a usage summary.

       -c, --config
              Load  options  from  a  file.  You can load more than one config
              file, and can mix them with command-line arguments.

              Note: This option can not be used from  within  a  configuration

       -q, --quiet
              Hides all messages except errors.

       -v, --verbose
              Print extra information during the capture process.

              Print the version number and exit.

       -l, --loop <frequency>
              Continually capture images. The time between images is specified
              in seconds.

              Default behaviour is to capture a single image and exit.

              Note: The time to capture the next image is calculated  relative
              to  the epoch, so an image will not be captured immediately when
              the program is first started.

       --offset <seconds>
              Sets the offset to use when calculating when the next  image  is
              due in loop mode. Value can be positive or negative.

       -b, --background
              Run  in  the background. In this mode stdout and console logging
              are unavailable.

       --pid <filename>
              Saves the PID of the background process to the  specified  file.
              Ignored when not using background mode.

       --log [file/syslog:]<filename>
              Redirect log messages to a file or syslog. For example

              --log output.log
              --log file:output.log
              --log syslog

       --gmt  Use  GMT instead of the local timezone when formatting text with

   Capture Options
       -d, --device [<prefix>:]<device name>
              Set the source or device to use. The source module  is  selected
              automatically unless specified in the prefix.

              Default is /dev/video0.

              Available source modules, in order of preference:

              V4L2 - Capture images from a V4L2 compatible video device.
              V4L1 - Capture images from a V4L1 compatible video device.
              FILE - Capture an image from a JPEG or PNG image file.
              RAW - Reads images straight from a device or file.
              TEST - Draws colour bars.

       -i, --input <input number or name>
              Set  the  input  to  use. You may select an input by either it’s
              number or name.

              Default is "0".

              List available inputs for the selected source or device.

              fswebcam -d v4l2:/dev/video1 --list-inputs

       -t, --tuner <tuner number>
              Set the tuner to use.

       -f, --frequency <frequency>
              Set the frequency of the selected input or tuner. The value  may
              be read as KHz or MHz depending on the input or tuner.

       -p, --palette <name>
              Try  to use the specified image format when capturing the image.

              Default is to select one automatically.

              Supported formats:


       -r, --resolution <dimensions>
              Set the image resolution of the source  or  device.  The  actual
              resolution  used  may  differ  if  the  source  or device cannot
              capture at the specified resolution.

              Default is "384x288".

       --fps <frames per second>
              Sets the frame rate of the capture device. This  currently  only
              works with certain V4L2 devices.

              Default is "0", let the device decide.

       -F, --frames <number>
              Set the number of frames to capture. More frames mean less noise
              in the final image, however capture times  will  be  longer  and
              moving objects may appear blurred.

              Default is "1".

       -S, --skip <number>
              Set  the number of frames to skip. These frames will be captured
              but won’t be use. Use this option if your camera sends some  bad
              or corrupt frames when it first starts capturing.

              Default is "0".

       -D, --delay <delay>
              Inserts  a  delay after the source or device has been opened and
              initialised, and before the capture begins.  Some  devices  need
              this  delay to let the image settle after a setting has changed.
              The delay time is specified in seconds.

       -R, --read
              Use read() to capture images. This can be slower but more stable
              with some devices.

              Default  is  to  use mmap(), falling back on read() if mmap() is

       -s, --set <name=value>
              Set a control. These are used by the source modules  to  control
              image or device parameters. Numeric values can be expressed as a
              percentage of there  maximum  range  or  a  literal  value,  for

              --set brightness=50% --set framerate=5

              Non-numeric controls are also supported:

              --set lights=on

              V4L2  features  a  type  of  control  called  a  ’button’. These
              controls do not take any  value,  but  trigger  an  action.  For

              --set "Restore Factory Settings"

              Control names and values are not case sensitive.

              Note:  Available  controls  will  vary  depending  in the source
              module  and  devices  used.  For  more   information   see   the
              --list-controls option.

              List  available  controls  and  their  current  values  for  the
              selected source module and device. For example:

              fswebcam -d v4l2:/dev/video2 --list-controls

   Output Options
       These options are performed in the order they  appear  on  the  command
       line,  only  effecting  images  output  later  on the command line. For

              fswebcam -r 640x480 output1.jpeg --scale 320x240 output2.jpeg

              Will  create  two  images,  "output1.jpeg"  containing  a   full
              resolution   copy  of  the  captured  image  and  "output2.jpeg"
              containing the same captured image but scaled to half the  size.

              Disable the banner.

              Position the banner at the top of the image.

              Position the banner at the bottom of the image.

              This is the default.

       --banner-colour <#AARRGGBB>
              Set  the  colour  of  the banner. Uses the web-style hexadecimal
              format (#RRGGBB) to describe the  colour,  and  can  support  an
              alpha channel (#AARRGGBB). Examples:

              "#FF0000" is pure red.
              "#80000000" is semi-transparent black.
              "#FF000000" is invisible (alpha channel is at maximum).
              Default is "#40263A93".

       --line-colour <#AARRGGBB>
              Set the colour of the divider line. See --banner-colour for more

              Default is "#00FF0000".

       --text-colour <#AARRGGBB>
              Set the  colour  of  the  text.  See  --banner-colour  for  more

              Default is "#00FFFFFF".

       --font <[file or font name]:[font size]>
              Set  the  font  used  in the banner. If no path is specified the
              path in the GDFONTPATH environment variable is searched for  the

              If no font size is specified the default of "10" will be used.

              Default is "luxisr:10".

              Disable the text shadow.

              Enable the text shadow.

              This is the default behaviour.

       --title <text>
              Set the main text, located in the top left of the banner.

              Clear the main text.

       --subtitle <text>
              Set  the  sub-title  text,  located  in  the  bottom left of the

              Clear the sub-title text.

       --timestamp <text>
              Set the timestamp text, located in the top right of the  banner.
              This string is formatted by strftime.

              Default is "%Y-%m-%d %H:%M (%Z)".

              Clear the timestamp text.

       --info <text>
              Set the info text, located in the bottom right of the banner.

              Clear the info text.

       --underlay <filename>
              Load  a PNG image and overlay it on the image, below the banner.
              The image is aligned to the top left.

              Note: The underlay is only applied when saving an image  and  is
              not modified by any of the image options or effects.

              Clear the underlay image.

       --overlay <filename>
              Load a PNG image and overlay on the image, above the banner. The
              image is aligned to the top left.

              Note: The overlay is only applied when saving an  image  and  is
              not modified by any of the image options or effects.

              Remove the overlay image.

       --jpeg <factor>
              Set JPEG as the output image format. The compression factor is a
              value between 0 and 95, or -1 for automatic.

              This is the default format, with a factor of "-1".

       --png <factor>
              Set PNG as the output image format. The compression  factor  can
              be a value between 0 and 9, or -1 for automatic.

       --save <filename>
              Saves the image to the specified filename.

              Note:  This isn’t necessary on the command-line where a filename
              alone is enough to save an image.

              Revert to the  original  captured  image  and  resolution.  This
              undoes all previous effects on the image.

              Note:  This  only reverts the image itself, and not options such
              as font, colours and overlay.

       --flip <direction[,direction]>
              Flips the image. Direction can be  (h)orizontal  or  (v)ertical.

              --flip h    Flips the image horizontally.
              --flip h,v  Flips the image both horizontally and vertically.

       --crop <dimensions[,offset]>
              Crop  the  image.  With  no  offset the cropped area will be the
              center of the image. Example:

              --crop 320x240    Crops the center 320x240 area of the image.
              --crop 10x10,0x0  Crops the 10x10 area at the top left corner of
              the image.

       --scale <dimensions>
              Scale the image.

              Example:  "--scale  640x480"  scales  the  image  up  or down to

              Note: The aspect ratio of the image is not maintained.

       --rotate <angle>
              Rotate the image in right angles (90, 180 and 270 degrees).

              Note: Rotating the  image  90  or  270  degrees  will  swap  the

              Apply a simple deinterlacer to the image.

              Invert all the colours in the image, creating a negative.

       --exec <command>
              Executes  the  specified  command  and  waits for it to complete
              before continuing. The command line is formatted by strftime.


       SIGHUP This causes fswebcam to reload it’s configuration.

              Causes fswebcam to capture an image immediately without  waiting
              on the timer in loop mode.


       The spacing between letters may be incorrect. This is an issue with the
       GD library.


       Please report bugs to <>.


        ncftpput(1), strftime(3)


       Written by Philip Heron <>.