zbarcam(1)

1ZBARCAM(1)                    ZBar Barcode Reader                   ZBARCAM(1)
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NAME

6       zbarcam - scan and decode bar codes from a video device
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SYNOPSIS

9       zbarcam [-qv] [--quiet] [--nodisplay] [--xml] [--verbose[=n]]
10               [--prescale=WxH] [-S[symbology.]config[=value]]
11               [--set [symbology.]config[=value]] [device]
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13       zbarcam {-h | --help | --version}
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DESCRIPTION

16       zbarcam scans a video4linux video source (eg, a webcam) for bar codes
17       and prints any decoded data to the standard output. The video stream is
18       also displayed to the screen.
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20       device is the path to the video4linux (version 1 or 2) character device
21       special file (major number 81 and minor number 0 thru 63). It defaults
22       to /dev/video0
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24       The underlying library currently supports EAN-13 (including UPC and
25       ISBN subsets), EAN-8, DataBar, DataBar Expanded, Code 128, Code 93,
26       Code 39, Codabar, Interleaved 2 of 5 and QR Code symbologies. The
27       specific type of each detected symbol is printed with the decoded data.
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OPTIONS

30       This program follows the usual GNU command line syntax. Single letter
31       options may be bundled, long options start with two dashes (`-').
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33       -h, --help
34           Print a short help message describing command line options to
35           standard output and exit
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37       --version
38           Print program version information to standard output and exit
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40       -v, --verbose[=n]
41           Increase debug output level. Multiple -v options create more spew.
42           Alternatively specify n to set the debug level directly
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44       -S[symbology.]config[=value], --set [symbology.]config[=value]
45           Set decoder configuration option config for symbology to value.
46           value defaults to 1 if omitted.  symbology is one of ean13, ean8,
47           upca, upce, isbn13, isbn10, i25, codabar, code39, code93, code128,
48           qrcode or the special value *. If symbology is omitted or *, the
49           config will be set for all applicable symbologies. These are the
50           currently recognized configs. Prefix a config with "no-" to negate
51           it. Not all configs are appropriate for every symbology.
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53           enable
54               Control decoding/reporting of a symbology. For symbologies
55               which are just subsets of ean13 (upca, upce, isbn13, isbn10),
56               this config controls whether the subsets are detected and
57               reported as such. These special cases are disabled by default,
58               all other symbologies default to enabled
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60           disable
61               Antonym for enable
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63           emit-check
64               Control whether check digits are included in the decoded
65               output. Enabled by default. This config does not apply for
66               code128, which never returns the check digit. It also not apply
67               for cases where the check digit is disabled (see add-check).
68               Check digits are currently not implemented for i25 or code39
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70           add-check
71               Enable decode and verification of a check digit for symbologies
72               where it is optional: this will include code39 and i25, neither
73               of which implements the check digit yet
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75           ascii
76               Enable escape sequences that encode the full ASCII character
77               set. This would apply to code39, except that it's not
78               implemented either...
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80           position
81               Enable collection of symbol position information. Enabled by
82               default. Currently, the position information is unusable, so
83               you can save a few cycles by disabling this.
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85           test-inverted
86               Specially for QR code images, sometimes the image is inverted,
87               e. g. lines are written in white instead of black. This option
88               makes ZBar to invert the image and parse again, in case it
89               fails using the normal order. Enabling it affects all decoders.
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91           min-length=n, max-length=n
92               Bound the number of decoded characters in a valid symbol. If a
93               decode result is outside the configured min/max range
94               (inclusive), it will not be reported. Set to 0 to disable the
95               corresponding check. This setting applies to variable-length
96               symbologies: i25, codabar, code39, code128 and pdf417.
97               min-length defaults to 6 for i25 and 1 for code39 (per Code 39
98               autodiscrimination recommendation); all others default to 0
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100           x-density=n, y-density=n
101               Adjust the density of the scanner passes. Lower values scan
102               more of the image at the cost of decreased performance. Setting
103               to 0 disables scanning along that axis. Defaults are both 1.
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105       -q, --quiet
106           Quiet operation; disable the audible beep otherwise emitted when a
107           symbol is decoded
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109       --nodisplay
110           Disable output video window. Video input will be scanned until the
111           program is interrupted or otherwise signaled
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113       --xml
114           Stream results using an XML output format. This format wraps the
115           raw data from the symbol with information about the scan in an easy
116           to parse format. The latest schema is available from
117           http://zbar.sourceforge.net/2008/barcode.xsd
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119       --raw
120           Use raw symbol data output format. This format prints symbol data
121           separated by newlines without the additional symbology type
122           information that is printed by default
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124       --prescale=WxH
125           Request video input scaling from the camera driver. Possibly useful
126           for reducing huge frames to achieve a higher frame rate. Note that
127           the driver may adjust or completely ignore the scaling request
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EXAMPLES

130       Scan for barcodes using the second video device and pipe the resulting
131       data through a script that searches for each code in a database and
132       does something useful with them:
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134           zbarcam /dev/video1 | upcrpc.py
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136       The upcrpc.py example script included in the examples/ subdirectory of
137       the distribution will make an XMLRPC call to a popular internet UPC
138       database and print the product description if found.
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140       Scan for barcodes using the default video device and stream results to
141       stdout in XML format, also disable recognition of Interleaved 2 of 5
142       codes to prevent confusion with other symbologies or background noise:
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144           zbarcam --xml -Si25.disable
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146       Scan only for Code 39, without using the preview window - maybe for a
147       fixed installation. To enable only Code 39, first all symbologies are
148       disabled, then Code 39 is re-enabled:
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150           zbarcam --nodisplay -Sdisable -Scode39.enable
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EXIT STATUS

154       zbarcam returns an exit code to indicate the status of the program
155       execution. Current exit codes are:
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157       0
158           Successful program completion.
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160       1
161           An error occurred. This includes bad arguments and I/O errors.
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163       2
164           A fatal error occurred.
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BUGS

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

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

179       Copyright © 2007-2010 Jeff Brown
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181       All Rights Reserved
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186zbar-0.22                         2017-04-11                        ZBARCAM(1)