pyBarcode Documentation - Read the Docs

pyBarcode DocumentationRelease 0.13.1

Thorsten Weimann

Apr 07, 2021

Contents

1 Contents 31.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.2 Create barcodes from the commandline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41.3 Provided barcodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41.4 python-barcode Writer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101.5 License . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Python Module Index 15

Index 17

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ii

pyBarcode Documentation, Release 0.13.1

Contents 1


2 Contents

CHAPTER 1

Contents

1.1 Introduction

This package was created to have barcodes available with pure-python. Pillow is required for exporting images (png,jpg), although not for SVGs.

All you need to create a barcode is to know the system (EAN, UPC, . . . ) and the code (e.g. for EAN-13:123456789102). As you see, you do not need the checksum, it will be calculated automatically. In some systems(Code 39) the checksum is optional, there you can give the add_checksum keyword argument (default is True).

1.1.1 Creating barcodes as SVG

To generate barcodes as SVG objects, you can use the default writer (simply not specify a writer).

Quick example:

>>> import barcode>>> ean = barcode.get('ean13', '123456789102')# Now we look if the checksum was added>>> ean.get_fullcode()'1234567891026'>>> filename = ean.save('ean13')>>> filename'ean13.svg'>>> options = dict(compress=True)>>> filename = ean.save('ean13', options)>>> filename'ean13.svgz'

Now you have ean13.svg and the compressed ean13.svgz in your current working directory. Open it and see the result.

3

https://python-pillow.org/


1.1.2 Creating barcodes as Image

New in version 0.4b1.

To generate barcodes as images, you must provide the ImageWriter to the get function. Without any options, theimages are rendered as PNG.

Quick example:

>>> import barcode>>> from barcode.writer import ImageWriter>>> ean = barcode.get('ean13', '123456789102', writer=ImageWriter())>>> filename = ean.save('ean13')>>> filename'ean13.png'

1.2 Create barcodes from the commandline

New in version 0.7beta4.

python-barcode ships with a little commandline script to generate barcodes without knowing Python. The install scriptdetects your Python version and adds the major version number to the executable script.

Usage:

$ python-barcode create "My Text" outfileNew barcode saved as outfile.svg.$ python-barcode create -t png "My Text" outfileNew barcode saved as outfile.png.$ python-barcode create -b ean8 -t jpeg "1234567" ean8_outNew barcode saved as ean8_out.jpg.

See python-barcode -h for more options.

1.3 Provided barcodes

1.3.1 Code 39

class barcode.codex.Code39(code, writer=None, add_checksum=True)Initializes a new Code39 instance.

Parameters

code [String] Code 39 string without * and checksum (added automatically if add_checksum isTrue).

writer [barcode.writer Instance] The writer to render the barcode (default: SVGWriter).

add_checksum [Boolean] Add the checksum to code or not (default: True).

get_fullcode()Returns the full code, encoded in the barcode.

Returns Full human readable code.

Return type String

4 Chapter 1. Contents


render(writer_options=None, text=None)Renders the barcode using self.writer.

Parameters

writer_options [Dict] Options for self.writer, see writer docs for details.

text [str] Text to render under the barcode.

Returns Output of the writers render method.

Class Hirarchy

Barcode Code39

1.3.2 Code 128

New in version 0.8beta1.

class barcode.codex.Code128(code, writer=None)Initializes a new Code128 instance. The checksum is added automatically when building the bars.

Parameters

code [String] Code 128 string without checksum (added automatically).




Return type String


Parameters




1.3. Provided barcodes 5


Class Hirachy

Barcode Code128

1.3.3 PZN

barcode.codex.PZNalias of barcode.codex.PZN7

Class Hirarchy

Barcode Code39 PZN7

1.3.4 EAN-13

class barcode.ean.EuropeanArticleNumber13(ean, writer=None, no_checksum=False)Initializes EAN13 object.

Parameters

ean [String] The ean number as string.


build()Builds the barcode pattern from self.ean.

Returns The pattern as string

Return type String

calculate_checksum()Calculates the checksum for EAN13-Code.

Returns The checksum for self.ean.

Return type Integer





Return type String


Parameters




to_ascii()Returns an ascii representation of the barcode.

Return type String

Class Hirarchy

Barcode EuropeanArticleNumber13

1.3.5 EAN-8

class barcode.ean.EuropeanArticleNumber8(ean, writer=None)Represents an EAN-8 barcode. See EAN13’s __init__ for details.

Parameters

ean [String] The ean number as string.


build()Builds the barcode pattern from self.ean.


Return type String

Class Hirarchy

Barcode EuropeanArticleNumber13 EuropeanArticleNumber8



1.3.6 JAN

class barcode.ean.JapanArticleNumber(jan, writer=None)Initializes JAN barcode.

Parameters

jan [String] The jan number as string.


Class Hirarchy

Barcode EuropeanArticleNumber13 JapanArticleNumber

1.3.7 ISBN-13

class barcode.isxn.InternationalStandardBookNumber13(isbn, writer=None)Initializes new ISBN-13 barcode.

Parameters

isbn [String] The isbn number as string.


Class Hirarchy

Barcode EuropeanArticleNumber13 InternationalStandardBookNumber13

1.3.8 ISBN-10

class barcode.isxn.InternationalStandardBookNumber10(isbn, writer=None)Initializes new ISBN-10 barcode. This code is rendered as EAN-13 by prefixing it with 978.

Parameters

isbn [String] The isbn number as string.




Class Hirarchy

Barcode EuropeanArticleNumber13 InternationalStandardBookNumber13 InternationalStandardBookNumber10

1.3.9 ISSN

class barcode.isxn.InternationalStandardSerialNumber(issn, writer=None)Initializes new ISSN barcode. This code is rendered as EAN-13 by prefixing it with 977 and adding 00 betweencode and checksum.

Parameters

issn [String] The issn number as string.


Class Hirarchy

Barcode EuropeanArticleNumber13 InternationalStandardSerialNumber

1.3.10 UPC-A

class barcode.upc.UniversalProductCodeA(upc, writer=None, make_ean=False)Universal Product Code (UPC) barcode.

UPC-A consists of 12 numeric digits.

build()Builds the barcode pattern from ‘self.upc’


Return type str

calculate_checksum()Calculates the checksum for UPCA/UPC codes

Returns The checksum for ‘self.upc’

Return type int





Return type String


Parameters




to_ascii()Returns an ascii representation of the barcode.

Return type str

Class Hirarchy

Barcode UniversalProductCodeA

1.4 python-barcode Writer

1.4.1 Common Writer Options

All writer take the following options (specified as keyword arguments to Barcode.save(filename, options) or set viaWriter.set_options(options), where options is a dictionary where keys are option names and values are option valuesto be set).

Note: See the documentation of the specific writer for special options, only available for this writer.

Common Options:

module_width The width of one barcode module in mm as float. Defaults to 0.2.

module_height The height of the barcode modules in mm as float. Defaults to 15.0.

quiet_zone Distance on the left and on the right from the border to the first (last) barcode module in mmas float. Defaults to 6.5.

font_path Path to the font file to be used. Defaults to DejaVuSansMono (which is bundled with thispackage).

font_size Font size of the text under the barcode in pt as integer. Defaults to 10.



text_distance Distance between the barcode and the text under it in mm as float. Defaults to 5.0.

background The background color of the created barcode as string. Defaults to white.

foreground The foreground and text color of the created barcode as string. Defaults to black.

New in version 0.6.

center_text If true (the default) the text is centered under the barcode else left aligned.

Note: Some barcode classes change the above defaults to fit in some kind of specification.

1.4.2 Writers

python-barcode SVGWriter

Creates barcodes as (compressed) SVG objects.

Special Options

In addition to the common writer options you can give the following special option.

Special Option:

compress Boolean value to output a compressed SVG object (.svgz). Defaults to False.

python-barcode ImageWriter

New in version 0.4b1.

Creates barcodes as image. All imagetypes supported by Pillow are available.

Special Options

In addition to the common writer options you can give the following special options.

Special Options:

format The image file format as string. All formats supported by Pillow are valid (e.g. PNG, JPEG,BMP, . . . ). Defaults to PNG.

dpi DPI as integer to calculate the image size in pixel. This value is used for all mm to px calculations.Defaults to 300.

1.4. python-barcode Writer 11


Create your own writer

To create your own writer, inherit from barcode.writer.BaseWriter. In your __init__ method call BaseWriter’s __init__and give your callbacks for initialize(raw_code), paint_module(xpos, ypos, width, color), paint_text(xpos, ypos) andfinish().

Now instatiate a new barcode and give an instance of your new writer as argument. If you now call render on thebarcode instance your callbacks get called.

1.4.3 API (autogenerated)

class barcode.writer.BaseWriter(initialize=None, paint_module=None, paint_text=None, fin-ish=None)

Baseclass for all writers.

Initializes the basic writer options. Childclasses can add more attributes and can set them directly or usingself.set_options(option=value).

Parameters

initialize [Function] Callback for initializing the inheriting writer. Is called: call-back_initialize(raw_code)

paint_module [Function] Callback for painting one barcode module. Is called: call-back_paint_module(xpos, ypos, width, color)

paint_text [Function] Callback for painting the text under the barcode. Is called: call-back_paint_text(xpos, ypos) using self.text as text.

finish [Function] Callback for doing something with the completely rendered output. Is called:return callback_finish() and must return the rendered output.

calculate_size(modules_per_line, number_of_lines, dpi=300)Calculates the size of the barcode in pixel.

Parameters

modules_per_line [Integer] Number of modules in one line.

number_of_lines [Integer] Number of lines of the barcode.

dpi [Integer] DPI to calculate.

Returns Width and height of the barcode in pixel.

Return type Tuple

register_callback(action, callback)Register one of the three callbacks if not given at instance creation.

Parameters

action [String] One of ‘initialize’, ‘paint_module’, ‘paint_text’, ‘finish’.

callback [Function] The callback function for the given action.

render(code)Renders the barcode to whatever the inheriting writer provides, using the registered callbacks.

Parameters

code [List] List of strings matching the writer spec (only contain 0 or 1).



save(filename, output)Saves the rendered output to filename.

Parameters

filename [String] Filename without extension.

output [String] The rendered output.

Returns The full filename with extension.

Return type String

set_options(options)Sets the given options as instance attributes (only if they are known).

Parameters

options [Dict] All known instance attributes and more if the childclass has defined thembefore this call.

Return type None

class barcode.writer.ImageWriter(format=’PNG’, mode=’RGB’)


Parameters




Return type String

write(content, fp: BinaryIO)Write content into a file-like object.

Content should be a barcode rendered by this writer.

class barcode.writer.SVGWriter


Parameters




Return type String

write(content, fp: BinaryIO)Write content into a file-like object.

Content should be a barcode rendered by this writer.

1.4. python-barcode Writer 13


1.5 License

python-barcode is distributed under the MIT license:

Copyright (c) 2017-2020 Hugo Osvaldo Barrera <[email protected]>, et alCopyright (c) 2010-2013 Thorsten Weimann

Permission is hereby granted, free of charge, to any person obtaining a copyof this software and associated documentation files (the "Software"), to dealin the Software without restriction, including without limitation the rightsto use, copy, modify, merge, publish, distribute, sublicense, and/or sellcopies of the Software, and to permit persons to whom the Software isfurnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included inall copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS ORIMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THEAUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHERLIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS INTHE SOFTWARE.


Python Module Index

bbarcode.writer, 12

15


16 Python Module Index

Index

Bbarcode.writer (module), 12BaseWriter (class in barcode.writer), 12build() (barcode.ean.EuropeanArticleNumber13

method), 6build() (barcode.ean.EuropeanArticleNumber8

method), 7build() (barcode.upc.UniversalProductCodeA

method), 9

Ccalculate_checksum() (bar-

code.ean.EuropeanArticleNumber13 method),6

calculate_checksum() (bar-code.upc.UniversalProductCodeA method),9

calculate_size() (barcode.writer.BaseWritermethod), 12

Code128 (class in barcode.codex), 5Code39 (class in barcode.codex), 4

EEuropeanArticleNumber13 (class in barcode.ean),

6EuropeanArticleNumber8 (class in barcode.ean),

7

Gget_fullcode() (barcode.codex.Code128 method),

5get_fullcode() (barcode.codex.Code39 method), 4get_fullcode() (bar-

code.ean.EuropeanArticleNumber13 method),6

get_fullcode() (bar-code.upc.UniversalProductCodeA method),9

IImageWriter (class in barcode.writer), 13InternationalStandardBookNumber10 (class

in barcode.isxn), 8InternationalStandardBookNumber13 (class

in barcode.isxn), 8InternationalStandardSerialNumber (class

in barcode.isxn), 9

JJapanArticleNumber (class in barcode.ean), 8

PPZN (in module barcode.codex), 6

Rregister_callback() (barcode.writer.BaseWriter

method), 12render() (barcode.codex.Code128 method), 5render() (barcode.codex.Code39 method), 4render() (barcode.ean.EuropeanArticleNumber13

method), 7render() (barcode.upc.UniversalProductCodeA

method), 10render() (barcode.writer.BaseWriter method), 12

Ssave() (barcode.writer.BaseWriter method), 12save() (barcode.writer.ImageWriter method), 13save() (barcode.writer.SVGWriter method), 13set_options() (barcode.writer.BaseWriter method),

13SVGWriter (class in barcode.writer), 13

Tto_ascii() (barcode.ean.EuropeanArticleNumber13

method), 7to_ascii() (barcode.upc.UniversalProductCodeA

method), 10

17


UUniversalProductCodeA (class in barcode.upc), 9

Wwrite() (barcode.writer.ImageWriter method), 13write() (barcode.writer.SVGWriter method), 13writer, 10writer_options, 10

18 Index

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