On Thu, Feb 21, 2008 at 12:14 AM, Magnus Manske magnusmanske@googlemail.com wrote:
<rant> I'm currently working on the Scott Forseman image donation, cutting large scanned images into smaller, manually optimized ones. The category containing the unprocessed images is http://commons.wikimedia.org/wiki/Category:ScottForesman-raw
It's shameful. Honestly. Look at it. We're the world's #9 top web site, and this is the best we can do?
Yes, I know that the images are large, both in dimensions (~5000x5000px) and size (5-15MB each). Yes, I know that ImageMagick has problems with such images. But honestly, is there no open source software that can generate a thumbnail from a 15MB PNG without nuking our servers?
It got me annoyed as well. So I finally got around writing a png resizer that does not need to load the entire file into memory: http://svn.wikimedia.org/viewvc/mediawiki/trunk/pngds/. I took a 6000x4000 PNG from that category and recompressed it to a 640px image in only 4 seconds, while taking only a few 100KB of memory.
Couple of downsides: * It does currently not do any adaptive filtering on compression, which may lead to somewhat larger file sizes than necessary * Compression level is hardcoded * Only RGB, RGBA, Grayscale and Grayscale-Alpha images are supported. Palette images are unsupported. * Single color transparency is discarded.
There should probably a MediaWiki mediahandler be written for this as well.
Bryan