These bindings provide an object oriented API to the potrace library.
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
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 .
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 .
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 .
Thanks to 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:
- potrace source: http://potrace.sourceforge.net/#downloading
- agg source: http://www.antigrain.com/download/index.html
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:
- "numpy/arrayobject.h":
C:/Python27/Lib/site-packages/numpy/core/include - potrace headers:
C:/src/potrace-1.11/src - agg headers:
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:
- potrace:
C:/src/potrace-1.11/src/.libs - agg:
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