On Mon, Jul 13, 2009 at 7:09 PM, J Elaych<[email protected]> wrote: > > Interesting, but I'm especially impressed by how well PIL stands up > to VIPS. It looks like vips was primarily designed to have a small > memory > imprint, especially for image files that are larger than physical > memory. PIL > takes only about 1.5 times as long as vips on a dual core processor, > so I > wonder how much of that may be due to PIL's inefficient use of > multiprocessors?
Yes. The more processors, the faster VIPS will be compared with PIL. > > A 1.5 times speedup doesn't seem to me to be a very compelling reason > to > drop PIL as the default imaging library, especially since PIL has a > nice python > interface and plays nicely with numpy. I couldn't find out how well > vips plays > with numpy --- is it easy (and fast) to convert back and forth between > vips > images and numpy arrays? I posted this question to the VIPS users list. John Cupitt replied that though it would be easy to write such a routine, it would be better to wait until Python 3.0 is out and supported by VIPS to do so. > > The PIL memory use looks kind of high, but I can't tell from those > tests if > thats a systemic problem related to large 5k x 5k arrays or if its a > standard > PIL overhead. If its related to a scaling factor of the size of the > array, then > 180M / 25M is a pretty big memory scale factor and could be an issue, > but > if there's just a constant overhead to PIL then its pretty easy to > ignore. VIPS is used for huge files (museum-quality scans and medical imaging data). > > I'd like to hear what other people think: is that factor of 1.5 or > 2.0 in speed > enough to motivate switching to vips for the default sage imaging > library? Is PIL really the default? I did not know that. I don't mean for my comments to be interpreted for or against PIL. I simply want to examine VIPS more carefully. I think PIL (for all its flaws) would be easier to wrap than VIPS. Though ease-of-use is a Sage goal, I think software quality is another and that is the issue I am worried about. I'm happy to hear arguments for/against any open source image processing software. --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
