segno 0.2.5

Segno – Python QR Code and Micro QR Code encoder

Segno is a QR Code and Micro QR Code encoder which has no further dependencies.

This package implements ISO/IEC 18004:2006(E) / ISO/IEC 18004:2015(E) “QR Code bar code symbology specification” and produces Micro QR Codes and QR Codes with nearly no effort.

Segno provides several serialization formats like Scalable Vector Graphics (SVG), Encapsulated PostScript (EPS), Portable Network Graphics (PNG), Portable Document Format (PDF), Portable Bitmap (PBM), Portable Arbitrary Map (PAM), LaTeX (PGF/TikZ), X PixMap (XBM), X Bitmap (XPM) or text output. None of these serializers require an external lib. Segno could provide more serialization formats via a plugin architecture. Further, it provides several high level function to create QR Codes which encode contact data (MeCard, vCard) or WIFI configurations.

Installation

Use pip to install segno from PyPI:

$ pip install segno

Usage

Command line

The command line script prints the QR Code to the terminal:

$ segno "Comfortably Numb"

To serialize the QR Code, use the “output” argument:

$ segno -o=raincoat.svg "Famous Blue Raincoat"
$ segno  --scale=10 --color=darkblue --border=0 --output=fire.svg "Who by Fire"
$ segno --scale=10 --background=transparent --output=miracle.png "Waiting for the Miracle"

Library

>>> import segno
>>> qr = segno.make('Up Jumped the Devil')  # Let Segno choose the minimal version
>>> qr.is_micro
False
>>> qr.version
2
>>> qr.error
'Q'
>>> qr.save('up-jumped-the-devil.png')  # Save as PNG
>>> qr.save('up-jumped-the-devil-2.png', scale=10)  # Scaling factor 10
>>> qr.save('up-jumped-the-devil-3.png', background=None)  # Transparent background
>>> qr.save('up-jumped-the-devil.pdf', scale=10)  # Save as PDF
>>> # SVG drawing the dark modules in "dark blue"
>>> qr.save('up-jumped-the-devil.svg', scale=10, color='darkblue')

If the content to encode is small enough, a Micro QR Code is generated:

>>> import segno
>>> qr = segno.make('RAIN')
>>> qr.is_micro
True
>>> qr.version
'M2'

If this behaviour is not desired, the user may use the factory functions segno.make_qr() which generates always QR Codes (never Micro QR Codes) or segno.make_micro() which generates always Micro QR Codes (or raises an error if the content is too large for a Micro QR Code).

>>> import segno
>>> mqr = segno.make_micro('THE BEATLES')
>>> mqr.version
'M3'
>>> qr = segno.make_qr('THE BEATLES')  # Same content but enforce a QR Code
>>> qr.version
1
>>> # This won't work since the data does not fit into a Micro QR Code M1 - M4
>>> mqr = segno.make_micro('Nick Cave and the Bad Seeds')
Traceback (most recent call last):
    ...
DataOverflowError: Data too large. No Micro QR Code can handle the provided data

All factory functions use the same parameters to specify the desired error level, version, data mask etc., see Segno’s documentation for details.

Documentation

Read the online documentation at <https://segno.readthedocs.io/>

Trademark

“QR Code” and “Micro QR Code” are registered trademarks of DENSO WAVE INCORPORATED.

Changes

0.2.5 – 2017-02-14

• Added experimental support for Structured Append (divide content into max. 16 QR Code symbols)
• Internal refactoring (i.e. segno/scripts/cmd.py -> segno/cli.py)
• Added -s shortcut to Segno’s command line interface to provide the scaling factor
• Added -b shortcut to Segno’s command line interface to provide the border / quiet zone
• CLI accepts unquoted, whitespace separated content: segno "Comfortably Numb" can be written as segno Comfortably Numb

0.2.4 – 2017-01-31

• Fixed #33: Some Micro QR Codes may be unreadable due to wrong format information. Further, M1 and M3 codes may be wrong due to wrong encoding of final data symbol character (8 bits instead of (correct) 4 bits). Thanks to Nicolas Boullis for the bug report, initial fix, tests and patience.
• Fixed #34: Change default error level from “M” to “L” to avoid surprises that the content does not fit into the provided version. This change is somewhat backwards incompatible.
• Fixed #35: Check of user supplied mask pattern index was wrong.
• Fixed #36: Wrong placement of codeword in M1 and M3 symbols.
• Fixed #37: Generation of M1 / M3 symbols fail if the data modules are completely filled.
• Fixed #38: Optimized mask pattern choosing algorithm: If the user supplied a preferred mask, the mask evaluation step is skipped and the preferred mask is chosen
• Added more internal checks to ensure correct (Micro) QR Codes; provided helpful exceptions
• Removed writers.get_writable (replaced by writers.writable)
• Added support for serializing QR Codes as XBM (X BitMap) (supports black / white images)
• Added support for serializing QR Codes as XPM (X PixMap) (supports colors and transparency)
• Added support for encoding contact information as vCard version 3.0 (segno.helpers)
• Added -V shortcut to Segno’s command line script to show version information
• Better test coverage for command line script
• Better test coverage for M1 and M3 symbols

0.2.3 – 2016-10-17

• Fixed #27: Email URI is wrong if CC or BCC is used.
• Fixed #32: Don’t add version attribute if SVG >= 2.0
• Deprecated writers.get_writable; use writers.writable writers.writable closes file-like objects automatically (if necessary); replace writable, must_close = writers.get_writable(filename_or_buffer, mode) with with writers.writable(filename_or_buffer, mode) as f
• Added option to PNG serializer to specify an optional DPI value (thanks to Markus Ueberall for support)
• Added PAM (Portable Arbitrary Map) as serialization format (supports colors and transparency)

0.2.2 – 2016-09-21

• Command line script reports Segno’s version (--ver) and the version is also mentioned in the help message (-h) (#24)
• Support for creating email addresses or complete messages (segno.helpers)
• Internal optimizations and more correct minimal version finding (#26)

0.2.1 – 2016-09-15

• Fixed Python packaging (source distribution did not work), again

0.2.0 – 2016-09-15

• Fixed Python packaging

0.1.9 – 2016-09-15

• Added “color” parameter to the LaTeX serializer to define the color of the dark modules.
• Fixed serious issue #23: Segno creates invalid QR Codes if boost_error is not disabled (enabled by default)

0.1.8 – 2016-09-14

• Removed utils.matrix_with_border_iter
• Fixed #21 (type error while writing to terminal under Windows)
• Added option to serialize QR Codes as LaTeX vector graphic
• Added module segno.helpers which provides additional factory funcitons to create common QR Codes like a WIFI configuration, a geo location or MeCard

0.1.7 – 2016-09-04

• Changed API: Added a feature to increase the error correction level if it fits. Disable this feature via boost_error=False (#16)
• Added --no-error-boost to the command line script to disable error correction level incrementation (#17)
• Command line script: Internal changes and better test coverage
• Added tests for issue #18
• Added PBM (P1 and P4) serialization.
• Deprecated utils.matrix_with_border_iter, use utils.matrix_iter
• utils.matrix_with_border_iter will be removed in the next release
• API change: QRCode.matrix_iter(border) -> QRCode.matrix_iter(scale=1, border=None)

0.1.6 – 2016-08-25

• Fixed setup

0.1.5 – 2016-08-24

• Added QRCode.matrix_iter(border) which returns an iterator over the matrix and includes the border (as light modules).
• Invalid (empty) SVG identifiers / class names are ignored and do not result into an invalid SVG document (issue #8).
• SVG serializer: If unit was set to None, an invalid SVG document was generated (issue #14).
• Better command line support:
  • The command line script recognizes all SVG options (#9)
  • Added --mode/-m, renamed --mask/-m to --pattern/-p (issue #10)
  • The script used an empty string as default value for the data to encode. The data to encode has no default value anymore (issue #11)
  • Added --no-ad to omit the comment Software in PNG images (issue #12)

0.1.4 – 2016-08-21

• Better terminal output
• Fixed issue #5: QRCode.terminal() uses a special output function (if it detects Windows) to support MS Windows which may not support ANSI escape codes.

0.1.3 – 2016-08-20

• Added command line script “segno”
• Registered new file extension “ans” which serializes the QR Code as ANSI escape code (same output as QRCode.terminal())
• Removed deprecated methods “eps”, “svg”, “png”, “pdf”, and “txt” from segno.QRCode
• Switched from nose tests to py.test

0.1.2 – 2016-08-17

• Updated docs
• Backwards incompatible change: Deprecated “eps”, “svg”, “png”, “pdf”, and “txt” methods from QRCode. Use QRCode.save. Methods will be removed in 0.1.3
• Fixed issue #3 (M1 and M3 codes may have undefined areas)
• Fixed issue #4 (wrong ‘error’ default value for encoder.encode(), factory function segno.make() wasn’t affected)

0.1.1 – 2016-08-14

• Initial release