Interlacing artefacts with HDTV movies in Quicktime

Hello,

I like to extract frames from a HDTV movie (1920 x 1080 , mpeg-
Format), because I need to process the frames.

I have Quicktime and the Quicktine MPEG plugin.

The problem seems to be in Quicktime: it only shows these
movies with a lot of interlacing artefacts when using the
MPEG-plugin. Unfortunately, I dont have the streams in a
different codec (I have a variety of streams here, Sony,
Hitachi, Pioneer HDTV demo movies). But they are all mpeg
format. This doesnt not seem to appear in files with .mov-
Format, only in .mpeg.

The image quality that quicktime produces looks like this here:
http://www.billiger-online.de/quicktimehdtv.png

Or, if we compare the quality of the same stream with Quicktime
(left) and Windows Media Player (right), it looks like this:
http://www.billiger-online.de/interlacing.png

Does anybody know how to extract frames from such movies without
the interlacing problem ? Or what do to do with Quicktime to
show these movies correctly ?

Best regards
HZ