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
Make sure you have the agg and potrace development packages installed (libagg-dev and libpotrace-dev on ubuntu) and run:
python setup.py 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
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