Since 2 good weeks i found this nice piece of software called "fly ds tv" which work like a charm.

With it i have the possibility to preview channels from the sat in optimum conditions.
I can alternatively use an external "directshow filter" and in my case i've got "ffdshow raw video filter" installed so i wanna use it especially the avisynth part but i'm not sure what i could do.I have no knowledge of how scripting or so few it's just ridiculous, hence this post.

I wanna know if people could help a bit maybe you have an experience... well hopefully.

My source is clear (decoder-> s-video->capture card) the only thing is about the blocking for example (sometimes not all the time) you can noticeably see blocks on mtv video's titles.
Waiting for some suggestions
here is an image to illustrate my point

Thanks Guys