NAME
barcode - a stand alone program to run the barcode
library
SYNOPSIS
barcode [-b - | string] [-e encoding] [-o -
| outfile] [ other-flags ]
DESCRIPTION
The information below is extracted from the
texinfo file, which is the preferred source of information.
The barcode program is a front-end to access some
features of the library from the command line. It is able to read
user supplied strings from the command line or a data file
(standard input by default) and encode all of them.
OPTIONS
barcode accepts the following options:
- --help or -h
- Print a usage summary and exit.
- -i filename
- Identify a file where strings to be encoded are read from. If
missing (and if -b is not used) it defaults to standard input. Each
data line of the input file will be used to create one barcode
output.
- -o filename
- Output file. It defaults to standard output.
- -b string
- Specify a single ``barcode'' string to be encoded. The option
can be used multiple times in order to encode multiple strings
(this will result in multi-page postscript output or a table of
barcodes if -t is specified). The strings must match the encoding
chosen; if it doesn't match the program will print a warning to
stderr and generate ``blank'' output (although not zero-length).
Please note that a string including spaces or other special
characters must be properly quoted.
- -e encoding
- encoding is the name of the chosen encoding format being
used. It defaults to the value of the environment variable
BARCODE_ENCODING or to auto detection if the environment is also
unset.
- -g geometry
- The geometry argument is of the form ``[<width> x
<height>] [+ <xmargin> + <ymargin>]'' (with no
intervening spaces). Unspecified margin values will result in no
margin; unspecified size results in default size. The specified
values represent print points by default, and can be inches,
millimeters or other units according to the -u option or the
BARCODE_UNIT environment variable. The argument is used to place
the printout code on the page. Note that an additional white margin
of 10 points is added to the printout. If the option is
unspecified, BARCODE_GEOMETRY is looked up in the environment, if
missing a default size and no margin (but the default 10 points)
are used.
- -t table-geometry
- Used to print several barcodes to a single page, this option is
meant to be used to print stickers. The argument is of the form
``<columns> x <lines> [+ <leftmargin> +
<bottommargin> [- <rightmargin> [-
<topmargin>]]]'' (with no intervening spaces); if missing,
the top and right margin will default to be the same as the bottom
and left margin. The margins are specified in print points or in
the chosen unit (see -u below). If the option is not specified,
BARCODE_TABLE is looked up in the environment, otherwise no table
is printed and each barcode will get its own page. The size (but
not the position) of a barcode item within a table can also be
selected using -g (see "geometry" above), without struggling with
external and internal margins. I still think management of
geometries in a table is suboptimal, but I can't make it better
without introducing incompatibilities.
- -m margin(s)
- Specifies an internal margin for each sticker in the table. The
argument is of the form ``<xmargin>,<ymargin>'' and the
margin is applied symmetrically to the sticker. If unspecified, the
environment variable BARCODE_MARGIN is used or a default internal
margin of 10 points is used.
- -n
- ``Numeric'' output: don't print the ASCII form of the code,
only the bars.
- -c
- No checksum character (for encodings that allow it, like code
39, other codes, like UPC or EAN, ignore this option).
- -E
- Encapsulated postscript (default is normal postscript). When
the output is generated as EPS only one barcode is encoded.
- -P
- PCL output. Please note that the Y direction goes from top to
bottom for PCL, and the origin for an image is the top-left corner
instead of the bottom-left
- -p pagesize
- Specify a non-default page size. The page size can be specified
in millimeters, inches or plain numbers (for example: "210x297mm",
"8.5x11in", "595x842"). A page specification as numbers will be
interpreted according to the current unit specification (see -u
below). If libpaper is available, you can also specify the page
size with its name, like "A3" or "letter" (libpaper is a standard
component of Debian GNU/Linux, but may be missing elsewhere). The
default page size is your system-wide default if libpaper is there,
A4 otherwise.
- -u unit
- Choose the unit used in size specifications. Accepted values
are ``mm'', ``cm'', ``in'' and ``pt''. By default, the program will
check BARCODE_UNIT in the environment, and assume points otherwise
(this behaviour is compatible with 0.92 and previous versions. If
-u appears more than once, each instance will modified the
behaviour for the arguments at its right, as the command line is
processes left to right. The program internally works with points,
and any size is approximated to the nearest multiple of one point.
The -u option affect -g (geometry), -t (table) and -p (page
size).
ENCODING TYPES
The program encodes text strings passed either on the command
line (with -b) or retrieved from standard input. The text
representation is interpreted according to the following rules.
When auto-detection of the encoding is enabled (i.e, no explicit
encoding type is specified), the encoding types are scanned to find
one that can digest the text string. The following list of
supported types is sorted in the same order the library uses when
auto-detecting a suitable encoding for a string.
- EAN
- The EAN frontend is similar to UPC; it accepts strings of
digits, 12 or 7 characters long. Strings of 13 or 8 characters are
accepted if the provided checksum digit is correct. I expect most
users to feed input without a checksum, though. The add-2 and add-5
extension are accepted for both the EAN-13 and the EAN-8 encodings.
The following are example of valid input strings: ``123456789012''
(EAN-13), ``1234567890128'' (EAN-13 wih checksum), ``1234567''
(EAN-8), ``12345670 12345'' (EAN-8 with checksum and add-5),
``123456789012 12'' (EAN-13 with add-2), ``123456789012 12345''
(EAN-13 with add-5).
- UPC
- The UPC frontend accepts only strings made up of digits (and,
if a supplemental encoding is used, a blank to separate it). It
accepts strings of 11 or 12 digits (UPC-A) and 6 or 7 or 8 digits
(UPC-E).
The 12th digit of UPC-A is the checksum and is added by the
library if not specified in the input; if it is specified, it must
be the right checksum or the code is rejected as invalid. For
UPC-E, 6 digit are considered to be the middle part of the code, a
leading 0 is assumed and the checksum is added; 7 digits are either
considered the initial part (leading digit 0 or 1, checksum
missing) or the final part (checksum specified, leading 0 assumed);
8 digits are considered to be the complete code, with leading 0 or
1 and checksum. For both UPC-A and UPC-E, a trailing string of 2
digits or 5 digits is accepted as well. Therefore, the following
are examples of valid strings that can be encoded as UPC:
``01234567890'' (UPC-A) ``012345678905'' (UPC-A with checksum),
``012345'' (UPC-E), ``01234567890 12'' (UPC-A, add-2) and
``01234567890 12345'' (UPC-A, add-5), ``0123456 12'' (UPC-E,
add-2). Please note that when setting BARCODE_ANY to auto-detect
the encoding to be used, 12-digit strings and 7-digit strings will
always be identified as EAN. This because I expect most user to
provide input without a checksum. If you need to specify
UPC-with-checksum as input you must explicitly set BARCODE_UPC as a
flag or use -e upc on the command line.
- ISBN
- ISBN numbers are encoded as EAN-13 symbols, with an optional
add-5 trailer. The ISBN frontend of the library accepts real ISBN
numbers and deals with any hyphen and, if present, the ISBN
checksum character before encoding data. Valid representations for
ISBN strings are for example: ``1-56592-292-1'', ``3-89721-122-X''
and ``3-89721-122-X 06900}''.
- code 128-B
- This encoding can represent all of the printing ASCII
characters, from the space (32) to DEL (127). The checksum digit is
mandatory in this encoding.
- code 128-C
- The ``C'' variation of Code-128 uses Code-128 symbols to
represent two digits at a time (Code-128 is made up of 104 symbols
whose interpretation is controlled by the start symbol being used).
Code 128-C is thus the most compact way to represent any even
number of digits. The encoder refuses to deal with an odd number of
digits because the caller is expected to provide proper padding to
an even number of digits. (Since Code-128 includes control symbols
to switch charset, it is theoretically possible to represent the
odd digit as a Code 128-A or 128-B symbol, but this tool doesn't
currently implement this option).
- code 128 raw
- Code-128 output represented symbol-by-symbol in the input
string. To override part of the problems outlined below in
specifying code128 symbols, this pseudo-encoding allows the used to
specify a list of code128 symbols separated by spaces. Each symbol
is represented by a number in the range 0-105. The list should
include the leading character.The checksum and the stop character
are automatically added by the library. Most likely this
pseudo-encoding will be used with BARCODE_NO_ASCII and some
external program to supply the printed text.
- code 39
- The code-39 standard can encode uppercase letters, digits, the
blank space, plus, minus, dot, star, dollar, slash, percent. Any
string that is only composed of such characters is accepted by the
code-39 encoder. To avoid loosing information, the encoder refuses
to encode mixed-case strings (a lowercase string is nonetheless
accepted as a shortcut, but is encoded as uppercase).
- interleaved 2 of 5
- This encoding can only represent an even number of digits (odd
digits are represented by bars, and even digits by the interleaving
spaces). The name stresses the fact that two of the five items
(bars or spaces) allocated to each symbol are wide, while the rest
are narrow. The checksum digit is optional (can be disabled via
BARCODE_NO_CHECKSUM). Since the number of digits, including the
checksum, must be even, a leading zero is inserted in the string
being encoded if needed (this is specifically stated in the specs I
have access to).
- code 128
- Automatic selection between alphabet A, B and C of the Code-128
standard. This encoding can represent all ASCII symbols, from 0
(NUL) to 127 (DEL), as well as four special symbols, named F1, F2,
F3, F4. The set of symbols available in this encoding is not easily
represented as input to the barcode library, so the following
convention is used. In the input string, which is a C-language
null-terminated string, the NUL char is represented by the value
128 (0x80, 0200) and the F1-F4 characters are represented by the
values 193-196 (0xc1-0xc4, 0301-0304). The values have been chosen
to ease their representation as escape sequences.
Since the shell doesn't seem to interpret escape sequences on
the command line, the "-b" option cannot be easily used to
designate the strings to be encoded. As a workaround you can resort
to the command echo, either within back-ticks or used separately to
create a file that is then fed to the standard-input of barcode --
assuming your echo command processes escape sequences. The newline
character is especially though to encode (but not impossible unless
you use a csh variant.
These problems only apply to the command-line tool; the use of
library functions doesn't give any problem. In needed, you can use
the ``code 128 raw'' pseudo-encoding to represent code128 symbols
by their numerical value. This encoding is used late in the
auto-selection mechanism because (almost) any input string can be
represented using code128.
- Codabar
- Codabar can encode the ten digits and a few special symbols
(minus, plus, dollar, colon, bar, dot). The characters ``A'',
``B'', ``C'' and ``D'' are used to represent four different
start/stop characters. The input string to the barcode library can
include the start and stop characters or not include them (in which
case ``A'' is used as start and ``B'' as stop). Start and stop
characters in the input string can be either all lowercase or all
uppercase and are always printed as uppercase.
- Plessey
- Plessey barcodes can encode all the hexadecimal digits.
Alphabetic digits in the input string must either be all lowercase
or all uppercase. The output text is always uppercase.
- MSI
- MSI can only encode the decimal digits. While the standard
specifies either one or two check digits, the current
implementation in this library only generates one check digit.
- code 93
- The code-93 standard can natively encode 48 different
characters, including uppercase letters, digits, the blank space,
plus, minus, dot, star, dollar, slash, percent, as well as five
special characters: a start/stop delimiter and four "shift
characters" used for extended encoding. Using this "extended
encoding" method, any standard 7-bit ASCII character can be
encoded, but it takes up two symbol lengths in barcode if the
character is not natively supported (one of the 48). The encoder
here fully implements the code 93 encoding standard. Any characters
natively supported (A-Z, 0-9, ".+-/$ encoded as such - for any
other characters (such as lower case letters, brackets,
parentheses, etc.), the encoder will revert to extended encoding.
As a note, the option to exclude the checksum will eliminate the
two modulo-47 checksums (called C and K) from the barcode, but this
probably will make it unreadable by 9 These checksums are specified
to be used at the firmware level, and their absence will be
interpreted as an invalid barcode.
PCL OUTPUT
While the default output is Postscript (possibly EPS), and
Postscript can be post-processed to almost anything, it is
sometimes desirable to create output directly usable by the
specific printer at hand. PCL is currently supported as an output
format for this reason. Please note that the Y coordinate for PCL
goes from top to bottom, while for Postscript it goes from bottom
to top. Consistently, while in Postscript you specify the
bottom-left corner as origin, for PCL you specify the top-left
corner.
Barcode output for PCL Printers (HP LaserJet and compatibles),
was developed using PCL5 Reference manuals from HP. that really
refers to these printers:
- LaserJet III, III P, III D, III Si,
- LaserJet 4 family
- LaserJet 5 family
- LaserJet 6 family
- Color LaserJet
- DeskJet 1200 and 1600.
However, barcode printing uses a very small subset of PCL,
probably also LaserJet II should print it without problem, but the
resulting text may be horrible.
The only real difference from one printer to another really
depends on which font are available in the printer, used in
printing the label associated to the bars (if requested).
Earlier LaserJet supports only bitmaps fonts, so these are not
"scalable". (Ljet II ?), Also these fonts, when available, have a
specified direction, and not all of them are available in both
Portrait and Landscape mode.
From LaserJet 4 series, (except 4L/5L that are entry-level
printers), Arial scalable font should be available, so it's the
"default font" used by this program.
LaserJet III series printers (and 4L, 5L), don't feature "Arial"
as a resident font, so you should use BARCODE_OUT_PCL_III instead
of BARCODE_OUT_PCL., and font the font used will be "Univers"
instead of "Arial".
Results on compatible printers, may depend on consistency of
PCL5 compatibility, in doubt, try BARCODE_OUT_PCL_III
PJL commands are not used here, as it's not very compatible.
Tested Printers:
- Hp LaserJet 4050
- Hp LaserJet 2100
- Epson N-1200 emul PCL
- Toshiba DP2570 (copier) + PCL option
- Epson EPL-7100 emul. HP LaserJet II: bars print fine but text
is bad.
BUGS
The current management of borders/margins is far from optimal.
The ``default'' margin applied by the library interferes with the
external representation, but I feel it is mandatory to avoid
creating barcode output with no surrounding white space (the
problem is especially relevant for EPS output).
EAN-128 is not (yet) supported. I plan to implement it pretty
soon and then bless the package as version 1.0.
SEE ALSO
AUTHORS
Alessandro Rubini <rubini@gnu.org> (maintainer)
Leonid A. Broukhis <leob@mailcom.com> (several
encodings)
Andrea Scopece <a.scopece@tin.it> (PCL output)