Fractal image compression and image compression in Office and similar programs

Question

I have read that fractal image compression can be capable of reconstructing images, and then reconstruct them in any scale.

I have seen that programs like Word (97, 2000) can include images which seem to be as small or smaller than the original one, if "special paste" is used, and that the image can be resized.

Is it possible that Word 97/2000 (and other programs, like modern web browsers) use fractal image compression to achieve what I described?

Does it have something to do with fractal compression at all, or is there some similar method?

Answer 1

Microsoft has been known to use Fractal compression, but this is not what is going on in Word. It is possible to scale up an image using many different interpolation methods. Bi-linear, and bi-cubic interpolation are the most common. Word appears, to my eye, to be using bi-cubic interpolation. Vector quantization can also be used to scale up images. It is important to realize that no new detail is gained by enlarging an image this way. Fractal decompression is interesting in that it generates detail, but this detail isn't, in fact, real, simply a convenient byproduct of that particular interpolation method.