colour blending

[Uwe Andersen]

Hi,

I have not a *real* krita question but rather a more fundamental question 
regarding colour handling.
But maybe you want to read (and answer) it anyhow...
I created a colour bar with a black, blue, red, magenta, green, cyan, yellow 
and a white bar.
I put the colours directly side by side. So if I take a look at e.g. the
blue-red-border at pixel level I see that a "blue" pixel is directly adjacent 
to a "red" one.
If I put this picture onto a video output(SDI) and then into a waveform 
monitor it shows some ugly overshots between each colour border.
I've taken a look into a "professional" colour bar (from a Tektronix TG700 
Video Generator) and found out that the colours fade from one to another 
using five pixel for blending. 
I think my solution putting the colours directly to each other introduced some
high frequencies at signal level.
My simple questions are: Is there some kind of filter (a low-pass filter??) to
eliminate these frequencies? Is there such a filter in Krita?
If yes, how is it named?

Kind regards and thank you for reading all this,
Uwe Andersen

P.S.: I created the colour bar directly in the YCbCr -Space(what is used on 
SDI) so that it can be excluded to be a colour model conversion problem.