1ZBARCAM(1) ZBar Barcode Reader ZBARCAM(1)
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6 zbarcam - scan and decode bar codes from a video device
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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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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, Interleaved 2 of 5 and QR Code symbologies. The specific type
27 of each detected symbol is printed with the decoded data.
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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, code39, code93, code128, qrcode or
48 the special value *. If symbology is omitted or *, the config will
49 be set for all applicable symbologies. These are the currently
50 recognized configs. Prefix a config with "no-" to negate it. Not
51 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 min-length=n, max-length=n
86 Bound the number of decoded characters in a valid symbol. If a
87 decode result is outside the configured min/max range
88 (inclusive), it will not be reported. Set to 0 to disable the
89 corresponding check. This setting applies to variable-length
90 symbologies: i25, code39, code128 and pdf417. min-length
91 defaults to 6 for i25 and 1 for code39 (per Code 39
92 autodiscrimination recommendation); all others default to 0
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94 x-density=n, y-density=n
95 Adjust the density of the scanner passes. Lower values scan
96 more of the image at the cost of decreased performance. Setting
97 to 0 disables scanning along that axis. Defaults are both 1.
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99 -q, --quiet
100 Quiet operation; disable the audible beep otherwise emitted when a
101 symbol is decoded
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103 --nodisplay
104 Disable output video window. Video input will be scanned until the
105 program is interrupted or otherwise signaled
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107 --xml
108 Stream results using an XML output format. This format wraps the
109 raw data from the symbol with information about the scan in an easy
110 to parse format. The latest schema is available from
111 http://zbar.sourceforge.net/2008/barcode.xsd
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113 --raw
114 Use raw symbol data output format. This format prints symbol data
115 separated by newlines without the additional symbology type
116 information that is printed by default
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118 --prescale=WxH
119 Request video input scaling from the camera driver. Possibly useful
120 for reducing huge frames to achieve a higher frame rate. Note that
121 the driver may adjust or completely ignore the scaling request
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124 Scan for barcodes using the second video device and pipe the resulting
125 data through a script that searches for each code in a database and
126 does something useful with them:
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128 zbarcam /dev/video1 | upcrpc.py
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130 The upcrpc.py example script included in the examples/ subdirectory of
131 the distribution will make an XMLRPC call to a popular internet UPC
132 database and print the product description if found.
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134 Scan for barcodes using the default video device and stream results to
135 stdout in XML format, also disable recognition of Interleaved 2 of 5
136 codes to prevent confusion with other symbologies or background noise:
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138 zbarcam --xml -Si25.disable
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140 Scan only for Code 39, without using the preview window - maybe for a
141 fixed installation. To enable only Code 39, first all symbologies are
142 disabled, then Code 39 is re-enabled:
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144 zbarcam --nodisplay -Sdisable -Scode39.enable
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148 zbarcam returns an exit code to indicate the status of the program
149 execution. Current exit codes are:
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151 0
152 Successful program completion.
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154 1
155 An error occurred. This includes bad arguments and I/O errors.
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157 2
158 A fatal error occurred.
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161 zbarimg(1)
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163 http://zbar.sf.net/
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166 See http://sf.net/tracker/?group_id=189236&atid=928515
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169 Jeff Brown <spadix@users.sourceforge.net>
170 Lead developer
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173 Copyright © 2007-2010 Jeff Brown
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175 All Rights Reserved
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180zbar-0.10 2009-10-23 ZBARCAM(1)