These bindings provide an object oriented API to the potrace
_ library.
The full API documentation is on <https://pythonhosted.org/pypotrace/>
_.
The bindings work with input images represented as numpy arrays::
import numpy as np
import potrace
# Make a numpy array with a rectangle in the middle
data = np.zeros((32, 32), np.uint32)
data[8:32-8, 8:32-8] = 1
# Create a bitmap from the array
bmp = potrace.Bitmap(data)
# Trace the bitmap to a path
path = bmp.trace()
# Iterate over path curves
for curve in path:
print "start_point =", curve.start_point
for segment in curve:
print segment
end_point_x, end_point_y = segment.end_point
if segment.is_corner:
c_x, c_y = segment.c
else:
c1_x, c1_y = segment.c1
c2_x, c2_y = segment.c2
Ubuntu
Install system dependencies::
$ sudo apt-get install build-essential python-dev libagg-dev libpotrace-dev pkg-config
Install pypotrace::
$ git clone https://github.com/flupke/pypotrace.git
$ cd pypotrace
$ pip install numpy
$ pip install .
CentOS/RedHat
Install system dependencies::
$ sudo yum -y groupinstall "Development Tools"
$ sudo yum -y install agg-devel potrace-devel python-devel
Install pypotrace::
$ git clone https://github.com/flupke/pypotrace.git
$ cd pypotrace
$ pip install numpy
$ pip install .
OSX
Install system dependencies::
$ brew install libagg pkg-config potrace
Install pypotrace::
$ git clone https://github.com/flupke/pypotrace.git
$ cd pypotrace
$ pip install numpy
$ pip install .
Windows
Thanks to klonuo <https://github.com/klonuo>
_ for the instructions
Here are instruction how to make this package work on Windows, by using MinGW system. Probably it can be done with Visual Studio, but I lack skills to make such magic.
So assuming user has MinGW available, additional two packages are needed:
I extracted both packages in my C:\src
folder. Both are easy to build by
executing ./configure; make
and ./autogen.sh; make
respectively, on
MSYS prompt.
After that, we need some variables to build pypotrace successfully:
First, includes paths:
C:/Python27/Lib/site-packages/numpy/core/include
C:/src/potrace-1.11/src
C:/src/agg-2.5
there is a little catch for agg includes, as paths referenced in cpp sources
point to agg2/*.h
while in downloaded agg package we don't have agg2
folder. For me it was easiest to rename C:/src/agg-2.5/include
to
C:/src/agg-2.5/agg2
and use C:/src/agg-2.5
as agg include folder.
Next, libdirs for libraries we build above:
C:/src/potrace-1.11/src/.libs
C:/src/agg-2.5/src
and we can make pypotrace build command, and execute it::
python setup.py build_ext -IC:/Python27/Lib/site-packages/numpy/core/include;C:/src/potrace-1.11/src;C:/src/agg-2.5 -LC:/src/potrace-1.11/src/.libs;C:/src/agg-2.5/src
Finally install the package::
C:\src\git\pypotrace>python setup.py install
running install
running build
running build_py
copying potrace\__init__.py -> build\lib.win32-2.7\potrace
copying potrace\agg\__init__.py -> build\lib.win32-2.7\potrace\agg
running build_ext
skipping 'potrace\_potrace.c' Cython extension (up-to-date)
skipping 'potrace\bezier.cpp' Cython extension (up-to-date)
skipping 'potrace/agg\curves.cpp' Cython extension (up-to-date)
running install_lib
creating C:\Python27\Lib\site-packages\potrace
creating C:\Python27\Lib\site-packages\potrace\agg
copying build\lib.win32-2.7\potrace\agg\curves.pyd -> C:\Python27\Lib\site-packages\potrace\agg
copying build\lib.win32-2.7\potrace\agg\__init__.py -> C:\Python27\Lib\site-packages\potrace\agg
copying build\lib.win32-2.7\potrace\bezier.pyd -> C:\Python27\Lib\site-packages\potrace
copying build\lib.win32-2.7\potrace\_potrace.pyd -> C:\Python27\Lib\site-packages\potrace
copying build\lib.win32-2.7\potrace\__init__.py -> C:\Python27\Lib\site-packages\potrace
byte-compiling C:\Python27\Lib\site-packages\potrace\agg\__init__.py to __init__.pyc
byte-compiling C:\Python27\Lib\site-packages\potrace\__init__.py to __init__.pyc
running install_egg_info
Writing C:\Python27\Lib\site-packages\pypotrace-0.1-py2.7.egg-info
You can check everything is working correctly by running the tests::
$ pip install '.[dev]'
$ nosetests -v
The documentation is hosted here: http://packages.python.org/pypotrace
A copy is also included in the doc/_build/html
directory of the source
distribution.
This project is hosted on github: http://github.com/flupke/pypotrace
.. _potrace: http://potrace.sourceforge.net/