David Joyner wrote: > Harald: > > I know this is an old question but my feeling was in wasn't really > answered properly, > possibly because I inadvertantly took it off track with a response > which had an aside on > SAGE searching.
Since it's come up several times, it might be worth material for inclusion in the FAQ. -Jason > > Since PIL has come up a few times on SAGE lists in vague ways, I > thought I'd try to > be more detailed. Here is a way using SAGE which might help. First, > it requires some preparation. > > I'll assume you have installed sage in SAGEROOT (an absolute > pathname). (I'm going > to go into more detail that I know you need Harald since I hope to help others > who might know less about SAGE too). > > You must install PIL from http://www.pythonware.com/products/pil/. Here's how: > > (a) download the tarball from a link on the URL mentioned above, say > http://effbot.org/downloads/Imaging-1.1.6.tar.gz; > (b) extract it to SAGEROOT/local/lib/python/site-packages > (c) cd SAGEROOT/local/lib/python2.5/site-packages/Imaging-1.1.6 > (d) run ../../../../bin/python setup.py install > (e) install ImageMagick (unless you have xv installed, which you > probably don't); > in ubuntu, it's > sudo apt-get install imagemagick (or sudo apt-cache search > imagemagick, and install > a bunch of related packages too); > (f) in sage, type > sage: from PIL import Image > sage: im = Image.open("PATH/mypic.jpg") > sage: im.show(command="display") > > Of course, im.[TAB] gives you more commands to play with and the online > tutorial > http://www.pythonware.com/library/pil/handbook/introduction.htm > helps too. > > Hope this is more helpful, even if it a little late. > > - David Joyner > > > On Thu, Apr 17, 2008 at 8:07 AM, Harald Schilly > <[EMAIL PROTECTED]> wrote: >> Hi >> >> A friend of mine want's to manipulate pictures (bitmap, in color). >> Basically, he want's to load and then represent them as a binary >> vector in Sage and then encode them using linear codes -> >> manipulations (errors) -> then back to an image and see how good the >> code worked. >> The one thing I don't know is what's the best and easiest way to get a >> binary representation of an image to be able to work with - a >> bijection from picture to binary vector in GF(2) and back. Maybe in >> different versions (each color channel separate or other methods). >> >> Harald > > > > --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
