+++ /dev/null
-This is barcode.info, produced by makeinfo version 4.0b from
-barcode.texinfo.
-
- This file is the User's Manual for the barcode library (version
-0.98).
-
-\1f
-File: barcode.info, Node: Top, Next: Overview, Prev: (dir), Up: (dir)
-
-Barcode tools
-*************
-
- This file documents version 0.98 of the barcode library and sample
-programs (March 2002).
-
-* Menu:
-
-* Overview::
-* The Barcode Object::
-* Supported Flags::
-* The API::
-* The barcode Executable::
-* Supported Encodings::
-* PCL Output::
-* Bugs and Pending Issues::
-
-\1f
-File: barcode.info, Node: Overview, Next: The Barcode Object, Prev: Top, Up: Top
-
-Overview
-********
-
- The "barcode" package is mainly a C library for creating bar-code
-output files. It also includes a command line front-end and (in a
-foreseeable future) a graphic frontend.
-
- The package is designed as a library because we think the main use
-for barcode-generation tools is inside more featured applications. The
-library addresses bar code printing as two distinct problems: creation
-of bar information and actual conversion to an output format. To this
-aim we use an intermediate representation for bar codes, which is
-currently documented in the `ps.c' source file (not in this document).
-
- Note that the library and the accompanying material is released
-according to the GPL license, not the LGPL one. A copy of the GPL is
-included in the distribution tarball.
-
-\1f
-File: barcode.info, Node: The Barcode Object, Next: Supported Flags, Prev: Overview, Up: Top
-
-The Underlying Data Structure
-*****************************
-
- Every barcode-related function acts on a data structure defined in
-the `barcode.h' header, which must be included by any C source file
-that uses the library. The header is installed by make install.
-
- The definition of the data structure is included here for reference:
-
- struct Barcode_Item {
- int flags; /* type of encoding and other flags */
- char *ascii; /* malloced */
- char *partial; /* malloced too */
- char *textinfo; /* information about text placement */
- char *encoding; /* code name, filled by encoding engine */
- int width, height; /* output units */
- int xoff, yoff; /* output units */
- int margin; /* output units */
- double scalef; /* requested scaling for barcode */
- int error; /* an errno-like value, in case of failure */
- };
-
- The exact meaning of each field and the various flags implemented are
-described in the following sections.
-
- Even though you won't usually need to act on the contents of this
-structure, some of the functions in the library receive arguments that
-are directly related to one or more of these fields.
-
-* Menu:
-
-* The Field List::
-* The Intermediate Representation::
-
-\1f
-File: barcode.info, Node: The Field List, Next: The Intermediate Representation, Prev: The Barcode Object, Up: The Barcode Object
-
-The Fields
-==========
-
-`int flags;'
- The flags are, as you may suspect, meant to specify the exact
- behaviour of the library. They are often passed as an argument to
- barcode functions and are discussed in the next section.
-
-`char *ascii;'
-`char *partial;'
-`char *textinfo;'
-`char *encoding;'
- These fields are internally managed by the library, and you are
- not expected to touch them if you use the provided API. All of
- them are allocated with malloc.
-
-`int width;'
-`int height;'
- They specify the width and height of the active barcode region
- (i.e., excluding the white margin), in the units used to create
- output data (for postscript they are points, 1/72th of an inch,
- 0.352 mm). The fields can be either assigned to in the structure
- or via Barcode_Position(), at your choice. If either value or
- both are left to their default value of zero, the output engine
- will assign default values according to the specified scaling
- factor. If the specified width is bigger than needed (according to
- the scaling factor), the output barcode will be centered in its
- requested region. If either the width of the height are too small
- for the specified scale factor, the output bar code will expand
- symmetrically around the requested region.
-
-`int xoff;'
-`int yoff;'
- The fields specify offset from the coordinate origin of the output
- engine (for postscript, position 0,0 is the lower left corner of
- the page). The fields can be either assigned to in the structure
- or via Barcode_Position(), at your choice. The offset specifies
- where the white margin begins, not where the first bar will be
- printed. To print real ink to the specified position you should
- set margin to 0.
-
-`int margin;'
- The white margin that will be left around the printed area of the
- bar code. The same margin is applied to all sides of the printed
- area. The default value for the margin is defined in `barcode.h'
- as BARCODE_DEFAULT_MARGIN (10).
-
-`double scalef;'
- The enlarge or shrink value for the bar code over its default
- dimension. The width and scalef fields interact deeply in the
- creation of the output, and a complete description of the issues
- appears later in this section.
-
-`int error;'
- The field is used when a barcode function fails to host an
- errno-like integer value.
-
-Use of the width and scalef fields.
------------------------------------
-
- A width unit is the width of the thinnest bar and/or space in the
-chosen code; it defaults to 1 point if the output is postscript or
-encapsulated postscript.
-
- Either or both the code width and the scale factor can be left
-unspecified (i.e., zero). The library deals with defaults in the
-following way:
-
-Both unspecified
- If both the width and the scale factor are unspecified, the scale
- factor will default to 1.0 and the width is calculated according
- to the actual width of the bar code being printed.
-
-Width unspecified
- If the width is not specified, it is calculated according to the
- values of scalef.
-
-Scale factor unspecified
- If the scale factor is not specified, it will be chosen so that
- the generated bar code exactly fits the specified width.
-
-Both specified
- The code will be printed inside the specified region according to
- the specified scale factor. It will be aligned to the left. If,
- however, the chosen width is too small for the specific bar code
- and scaling factor, then the code will extend symmetrically to the
- left and to the right of the chosen region.
-
-\1f
-File: barcode.info, Node: The Intermediate Representation, Prev: The Field List, Up: The Barcode Object
-
-The Intermediate Representation
-===============================
-
- The encoding functions print their output into the partial and
-texinfo fields of the barcode data structure. Those fields, together
-with position information, are then used to generate actual output.
-This is an informal description of the intermediate format.
-
- The first char in partial tells how much extra space to add to the
-left of the bars. For EAN-13, it is used to leave space to print the
-first digit, other codes may have '0' for no-extra-space-needed.
-
- The next characters are alternating bars and spaces, as multiples of
-the base dimension which is 1 unless the code is rescaled. Rescaling is
-calculated as the ratio from the requested width and the calculated
-width. Digits represent bar/space dimensions. Lower-case letters
-represent those bars that should extend lower than the others: 'a' is
-equivalent to '1', 'b' is '2' and so on up to 'i' which is equivalent to
-'9'. Other letters will be used for encoding-specific meanings, as soon
-as I implement them.
-
- The textinfo string is made up of fields %lf:%lf:%c separated by
-blank space. The first integer is the x position of the character, the
-second is the font size (before rescaling) and the char item is the
-character to be printed.
-
- Both the partial and textinfo strings may include "-" or "+" as
-special characters (in textinfo the char should be a stand-alone word).
-They state where the text should be printed: below the bars ("-",
-default) or above the bars. This is used, for example, to print the
-add-5 and add-2 codes to the right of UPC or EAN codes (the add-5
-extension is mostly used in ISBN codes).
-
-\1f
-File: barcode.info, Node: Supported Flags, Next: The API, Prev: The Barcode Object, Up: Top
-
-The Flags
-*********
-
- The following flags are supported by version 0.98 of the library:
-
-`BARCODE_ENCODING_MASK'
- The mask is used to extract the encoding-type identifier from the
- flags field.
-
-`BARCODE_EAN'
-`BARCODE_UPC'
-`BARCODE_ISBN'
-`BARCODE_128B'
-`BARCODE_128C'
-`BARCODE_128'
-`BARCODE_128RAW'
-`BARCODE_39'
-`BARCODE_I25'
-`BARCODE_CBR'
-`BARCODE_MSI'
-`BARCODE_PLS'
-`BARCODE_93'
- The currently supported encoding types: EAN (13 digits, 8 digits,
- 13 + 2 add-on and 13 + 5 add-on), UPC (UPC-A, UPC-E, UPC-A with 2
- or 5 digit add-on), ISBN (with or without the 5-digit add-on),
- CODE128-B (the whole set of printable ASCII characters), CODE128-C
- (two digits encoded by each barcode symbol), CODE128 (all ASCII
- values), a "raw-input" pseudo-code that generates CODE128 output,
- CODE39 (alphanumeric), "interleaved 2 of 5" (numeric), Codabar
- (numeric plus a few symbols), MSI (numeric) and Plessey (hex
- digits). *Note Supported Encodings::.
-
-`BARCODE_ANY'
- This special encoding type (represented by a value of zero, so it
- will be the default) tells the encoding procedure to look for the
- first encoding type that can deal with a textual string.
- Therefore, a 11-digit code will be printed as UPC (as well as
- 6-digit, 11+2 and 11+5), a 12-digit (or 7-digit, or 12+2 or 12+5)
- as EAN13, an ISBN code (with or without hyphens, with or without
- add-5) will be encoded in its EAN13 representation, an even number
- of digits is encoded using CODE128C and a generic string is
- encoded using CODE128B. Since code-39 offers a much larger
- representation for the same text string, code128-b is preferred
- over code39 for alphanumeric strings.
-
-`BARCODE_NO_ASCII'
- Instructs the engine not to print the ascii string on output. By
- default the bar code is accompanied with an ascii version of the
- text it encodes.
-
-`BARCODE_NO_CHECKSUM'
- Instructs the engine not to add the checksum character to the
- output. Not all the encoding types can drop the checksum; those
- where the checksum is mandatory (like EAN and UPC) just ignore the
- flag.
-
-`BARCODE_OUTPUT_MASK'
- The mask is used to extract the output-type identifier from the
- flags field.
-
-`BARCODE_OUT_PS'
-`BARCODE_OUT_EPS'
-`BARCODE_OUT_PCL'
-`BARCODE_OUT_PCL_III'
- The currently supported encoding types: full-page postscript and
- encapsulated postscript; PCL (print command language, for HP
- printers) and PCL-III (same as PCL, but uses a font not available
- on older printers).
-
-`BARCODE_OUT_NOHEADERS'
- The flag instructs the printing engine not to print the header and
- footer part of the file. This makes sense for the postscript
- engine but might not make sense for other engines; such other
- engines will silently ignore the flag just like the PCL back-end
- does.
-
-\1f
-File: barcode.info, Node: The API, Next: The barcode Executable, Prev: Supported Flags, Up: Top
-
-Functions Exported by the Library
-*********************************
-
- The functions included in the barcode library are declared in the
-header file barcode.h. They perform the following tasks:
-
-`struct Barcode_Item *Barcode_Create(char *text);'
- The function creates a new barcode object to deal with a specified
- text string. It returns NULL in case of failure and a pointer to
- a barcode data structure in case of success.
-
-`int Barcode_Delete(struct Barcode_Item *bc);'
- Destroy a barcode object. Always returns 0 (success)
-
-`int Barcode_Encode(struct Barcode_Item *bc, int flags);'
- Encode the text included in the bc object. Valid flags are the
- encoding type (other flags are ignored) and BARCODE_NO_CHECKSUM
- (other flags are silently ignored); if the flag argument is zero,
- bc->flags will apply. The function returns 0 on success and -1 in
- case of error. After successful termination the data structure
- will host the description of the bar code and its textual
- representation, after a failure the error field will include the
- reason of the failure.
-
-`int Barcode_Print(struct Barcode_Item *bc, FILE *f, int flags);'
- Print the bar code described by bc to the specified file. Valid
- flags are the output type, BARCODE_NO_ASCII and
- BARCODE_OUT_NOHEADERS, other flags are ignored. If any of these
- flags is zero, it will be inherited from bc->flags which therefore
- takes precedence. The function returns 0 on success and -1 in case
- of error (with bc->error set accordingly). In case of success, the
- bar code is printed to the specified file, which won't be closed
- after use.
-
-`int Barcode_Position(struct Barcode_Item *bc, int wid, int hei, int xoff, int yoff, double scalef);'
- The function is a shortcut to assign values to the data structure.
-
-`int Barcode_Encode_and_Print(char *text, FILE *f, int wid, int hei, int xoff, int yoff, int flags);'
- The function deals with the whole life of the barcode object by
- calling the other functions; it uses all the specified flags.
-
-`int Barcode_Version(char *versionname);'
- Returns the current version as an integer number of the form major
- * 10000 + minor * 100 + release. Therefore, version 1.03.5 will be
- returned as 10305 and version 0.53 as 5300. If the argument is
- non-null, it will be used to return the version number as a
- string. Note that the same information is available from two
- preprocessor macros: BARCODE_VERSION (the string) and
- BARCODE_VERSION_INT (the integer number).
-
-\1f
-File: barcode.info, Node: The barcode Executable, Next: Supported Encodings, Prev: The API, Up: Top
-
-The barcode frontend program
-****************************
-
- 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.
-
-* Menu:
-
-* The Command Line::
-
-\1f
-File: barcode.info, Node: The Command Line, Prev: The barcode Executable, Up: The barcode Executable
-
-The Command Line
-================
-
- 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).
-
-\1f
-File: barcode.info, Node: Supported Encodings, Next: PCL Output, Prev: The barcode Executable, Up: Top
-
-Supported Encodings
-*******************
-
- 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, ".+-/$&%") will be 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 99% of all scanning systems.
- These checksums are specified to be used at the firmware level,
- and their absence will be interpreted as an invalid barcode.
-
-\1f
-File: barcode.info, Node: PCL Output, Next: Bugs and Pending Issues, Prev: Supported Encodings, Up: Top
-
-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.
-
-\1f
-File: barcode.info, Node: Bugs and Pending Issues, Prev: PCL Output, Up: Top
-
-Bugs and Pending Issues.
-************************
-
- 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.
-
-
-\1f
-Tag Table:
-Node: Top\7f154
-Node: Overview\7f526
-Node: The Barcode Object\7f1404
-Node: The Field List\7f2821
-Node: The Intermediate Representation\7f6586
-Node: Supported Flags\7f8359
-Node: The API\7f11343
-Node: The barcode Executable\7f14029
-Node: The Command Line\7f14458
-Node: Supported Encodings\7f19557
-Node: PCL Output\7f28997
-Node: Bugs and Pending Issues\7f31316
-\1f
-End Tag Table
projects / glabels / blobdiff