Originally Posted by NiLuJe
... while the upscaling algorithm is good, it's still an image upscaling algorithm, so a bit of blurriness is to be expected (we're not in CSI, where pixels magically appear from outer space when zooming ^^). ...
Actually, there are some "super-resolution
" algorithms that do an excellent job of upscaling WITHOUT "blurriness". Although they cannot create missing detail when upscaling, they do an excellent job of creating "natural looking" (false) details. The simplest method is interpolating only in the direction of least-gradient. This is similar to converting from raster to vector and rendering the upscaled vector image. The more complex (but more natural looking at high magnification) is "fractal scaling
". The "least-gradient
" upscaling is more suitable to a kindle -- it is commonly used in digital cameras as part of the "demosaicing
Of course, for criminal forensics investigations, that natural looking (but false) detail would not hold up in court. But it COULD make a book cover look "prettier" when upscaling.
EDIT: When it comes to Hollywood "technology", a nice companion to "infinite zoom" is "uncrop", as shown here: