NAME

       zbarcam - scan and decode bar codes from a video device

SYNOPSIS

       zbarcam [-qv] [--quiet] [--nodisplay] [--xml] [--verbose[=n]] [--prescale=WxH]
               [-S[symbology.]config[=value]] [--set [symbology.]config[=value]] [device]

       zbarcam {-h | --help | --version}

DESCRIPTION

       zbarcam scans a video4linux video source (eg, a webcam) for bar codes and prints any
       decoded data to the standard output. The video stream is also displayed to the screen.

       device is the path to the video4linux (version 1 or 2) character device special file
       (major number 81 and minor number 0 thru 63). It defaults to /dev/video0

       The underlying library currently supports EAN-13 (including UPC and ISBN subsets), EAN-8,
       DataBar, DataBar Expanded, Code 128, Code 93, Code 39, Codabar, Interleaved 2 of 5 and QR
       Code symbologies. The specific type of each detected symbol is printed with the decoded
       data.

OPTIONS

       This program follows the usual GNU command line syntax. Single letter options may be
       bundled, long options start with two dashes (`-').

       -h, --help
           Print a short help message describing command line options to standard output and exit

       --version
           Print program version information to standard output and exit

       -v, --verbose[=n]
           Increase debug output level. Multiple -v options create more spew. Alternatively
           specify n to set the debug level directly

       -S[symbology.]config[=value], --set [symbology.]config[=value]
           Set decoder configuration option config for symbology to value.  value defaults to 1
           if omitted.  symbology is one of ean13, ean8, upca, upce, isbn13, isbn10, i25,
           codabar, code39, code93, code128, qrcode or the special value *. If symbology is
           omitted or *, the config will be set for all applicable symbologies. These are the
           currently recognized configs. Prefix a config with "no-" to negate it. Not all configs
           are appropriate for every symbology.

           enable
               Control decoding/reporting of a symbology. For symbologies which are just subsets
               of ean13 (upca, upce, isbn13, isbn10), this config controls whether the subsets
               are detected and reported as such. These special cases are disabled by default,
               all other symbologies default to enabled

           disable
               Antonym for enable

           emit-check
               Control whether check digits are included in the decoded output. Enabled by
               default. This config does not apply for code128, which never returns the check
               digit. It also not apply for cases where the check digit is disabled (see
               add-check). Check digits are currently not implemented for i25 or code39

           add-check
               Enable decode and verification of a check digit for symbologies where it is
               optional: this will include code39 and i25, neither of which implements the check
               digit yet

           ascii
               Enable escape sequences that encode the full ASCII character set. This would apply
               to code39, except that it's not implemented either...

           position
               Enable collection of symbol position information. Enabled by default. Currently,
               the position information is unusable, so you can save a few cycles by disabling
               this.

           test-inverted
               Specially for QR code images, sometimes the image is inverted, e. g. lines are
               written in white instead of black. This option makes ZBar to invert the image and
               parse again, in case it fails using the normal order. Enabling it affects all
               decoders.

           min-length=n, max-length=n
               Bound the number of decoded characters in a valid symbol. If a decode result is
               outside the configured min/max range (inclusive), it will not be reported. Set to
               0 to disable the corresponding check. This setting applies to variable-length
               symbologies: i25, codabar, code39, code128 and pdf417.  min-length defaults to 6
               for i25 and 1 for code39 (per Code 39 autodiscrimination recommendation); all
               others default to 0

           x-density=n, y-density=n
               Adjust the density of the scanner passes. Lower values scan more of the image at
               the cost of decreased performance. Setting to 0 disables scanning along that axis.
               Defaults are both 1.

       -q, --quiet
           Quiet operation; disable the audible beep otherwise emitted when a symbol is decoded

       --nodisplay
           Disable output video window. Video input will be scanned until the program is
           interrupted or otherwise signaled

       --xml
           Stream results using an XML output format. This format wraps the raw data from the
           symbol with information about the scan in an easy to parse format. The latest schema
           is available from http://zbar.sourceforge.net/2008/barcode.xsd

       --raw
           Use raw symbol data output format. This format prints symbol data separated by
           newlines without the additional symbology type information that is printed by default

       --prescale=WxH
           Request video input scaling from the camera driver. Possibly useful for reducing huge
           frames to achieve a higher frame rate. Note that the driver may adjust or completely
           ignore the scaling request

EXAMPLES

       Scan for barcodes using the second video device and pipe the resulting data through a
       script that searches for each code in a database and does something useful with them:

           zbarcam /dev/video1 | upcrpc.py

       The upcrpc.py example script included in the examples/ subdirectory of the distribution
       will make an XMLRPC call to a popular internet UPC database and print the product
       description if found.

       Scan for barcodes using the default video device and stream results to stdout in XML
       format, also disable recognition of Interleaved 2 of 5 codes to prevent confusion with
       other symbologies or background noise:

           zbarcam --xml -Si25.disable

       Scan only for Code 39, without using the preview window - maybe for a fixed installation.
       To enable only Code 39, first all symbologies are disabled, then Code 39 is re-enabled:

           zbarcam --nodisplay -Sdisable -Scode39.enable

EXIT STATUS

       zbarcam returns an exit code to indicate the status of the program execution. Current exit
       codes are:

       0
           Successful program completion.

       1
           An error occurred. This includes bad arguments and I/O errors.

       2
           A fatal error occurred.

SEE ALSO

       zbarimg(1)

       http://zbar.sf.net/

BUGS

       See http://sf.net/tracker/?group_id=189236&atid=928515

AUTHOR

       Jeff Brown <spadix@users.sourceforge.net>
           Lead developer

COPYRIGHT

       Copyright © 2007-2010 Jeff Brown

       All Rights Reserved