JpegMap::blur(): The middle value is a little bit weaker now.
The RGB values were set and read wrong because i didn't think about the
big endian-/little endianness.
The outer region, inner cardioid and circle at the left are completely
let out of the calculation.

I substituted my formulas by the ones found on wikipedia.
Improved the smoothness of the color values.
Set the JPEG quality from 75 to 95.