My Java application  converts websites to Plucker documents for
offline reading on handhelds. One of its tasks is to rescale images to
make them fit on a Palm screen, the resolution of which is typically
160x160 or 320x320.
To rescale images to thumbnails, I use a bilinear filter from the Java
2D class library. This filter gives a slightly fuzzy look to the
thumbnail images because pixels are blended to give a smooth,
The problem with this approach is that the thumbnail image data does not
lend itself well to compression because of the increase in colors
created by the bilinear filter.
Now I'm looking for a rescaling algorithm that does not create as many
colors as bilinear filter but offers better quality than the the nearest
neighbor algorithm (the other filter offered by Java 2D), which is too
coarse and tends to "drop" pixels.
Any ideas for rescaling algorithms?