Writers¶
Common Writer Options¶
All writer take the following options (specified as keyword arguments to
Barcode.save(filename, options)
or set via Writer.set_options(options)
, where
options
is a dictionary where keys are option names and values are option values to
be set).
Note
See the documentation of the specific writer for special options, only available for this writer.
- 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 mm as float. Defaults to 6.5.
- font_path
Path to the font file to be used. Defaults to DejaVuSansMono (which is bundled with this package).
- font_size
Font size of the text under the barcode in pt as integer. Font size zero suppresses text. 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.
- center_text
If true (the default) the text is centered under the barcode else left aligned.
New in version 0.6.
Note
Some barcode classes change the above defaults to fit in some kind of specification.
SVGWriter¶
Renders barcodes as [optionally, compressed] SVG objects.
In addition to the common writer options you can give the following special option.
- compress
Boolean value to output a compressed SVG object (.svgz). Defaults to
False
ImageWriter¶
New in version 0.4b1.
Renders barcodes as image. Supports all the image formats supported by Pillow.
In addition to the common writer options you can give the following special options:
- format
The image file format as
str
. All formats supported by Pillow are valid (e.g. PNG, JPEG, BMP, …). Defaults toPNG
.- dpi
DPI as
int
to calculate the image size in pixel. This value is used for all mm to px calculations. Defaults to300
Custom writers¶
It’s possible to create your own writer by inheriting 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)
finish()
Now instantiate a new barcode and give an instance of your new writer as argument. If
you now call render
on the barcode instance your callbacks get called.
Creating compressed SVGs¶
Saving a compressed SVG (SVGZ):
>>> 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.