Looking for a bunch of optimized image processing utility functions. Like: Resize with Cubic Interpolation, Rotate, Crop, Change a Color to a different Color. Much like what the GIMP has. But without the license and bloat of The GIMP.
- Must be Free and Open Source, preferably not GPL, unless it is best
- Must have comprehensive / good documentation for beginners (to image processing).
- Must be faster than ImageMagick, or any of its forks (GraphicsMagick).
- Must include a bunch of ‘actual algorithms‘, in the vein of a image manipulator like The Gimp. Not just a bunch scientific algorithms for which I have no use.
…
- Doesn’t need to support image file formats (e.g. import from a GIF).
- Doesn’t need to support more than 24-bit color.
- Doesn’t need to be the fastest, but speed needs to be better than academic.
Answer
I am using ImageMagick (or Magick++ its library) to render the final GIF animation because it is relatively fast at doing so. For the rest, the operations are so simple that I am using the ‘unofficial’ GIF decoder library from sourceforge to decode to a array. Then, taking the array of raw image data and; Crop / Color Change in a standard C++ for-loop.
For True Super Optimized uses, it looks like other people on StackOverflow are recommending OpenCV or Boost's GIL (by Adobe). They both contain good primitives and OpenCV also contains alot more algorithms which are optimized for speed.
Your question looks very subjective. Still look at the Boost Generic Image Library, it is open source.