STMP artefact?

[manum]

Hello,
I've some little artefacts when I use a STMAP node to map a texture. Is my stmp settings could generate this (I try differents settings but nothing improve the result), or is my UV pass not enough define? (I rendered it twice of my final size)

[manum]

Ok, I found this on the web: "You also get this when the UV shells are too close to each other or
too close to the edges of the frame and the resolution of the uv map
isn't high enough to compensate for that because of filtering."

[manum]

One more thing for people who meet the same problem:
When you reformat your UV map, "Impulse" filter in the reformat node gives me much better result.