Re: Image warping in Python or PIL
Oliver Tonnhofer <[email protected]>
| Newsgroups | gmane.comp.python.image |
|---|---|
| Message-ID | <[email protected]> |
On 08.05.2010, at 13:49, Fredrik Lundh wrote: > The transform(MESH) operation might be what you need. > > http://effbot.org/tag/PIL.Image.Image.transform > > Instead of mapping between individual pixels, cover the output image > with a grid, and calculate the source pixels for the corners of each > grid rectangle (forming a quadrilateral area). Pass in the resulting > list of (grid rectangle, quadrilateral) pairs to transform(MESH), and > it'll take care of the rest. That's what I used to transform maps/aerial images from one coordinate system to another. http://bitbucket.org/olt/mapproxy/src/142/mapproxy/core/image.py#cl-553 > The result is (usually) an approximation, with the maximum error > controlled by the grid resolution. I did tests with 1500x1500px and there where no improvements beyond 8x8. The performance is really great. Even faster than GDAL which is a C library for exactly this kind of image processing. Regards, Oliver _______________________________________________ Image-SIG maillist - [email protected] http://mail.python.org/mailman/listinfo/image-sig