ATSC artifacts: encoder or decoder ?

Hi All,


I recently got my Sony KDL-46XBR2 hooked up to

an OTA HDTV antenna. I noticed that in all hi-def

channels, 1080i and 720p, there are small but many

motion or pixel artifacts. Most noticeable along edges

of regions.


I also notice this when I hook up my ATI HDTV wonder

and receive the same channels on my computer monitor.


Being a newbie, I wonder if someone can me if these

are encoder artifacts (from the source) or decoder

artifacts (in the TV or driver, with pixels being tossed out to

stay in sync) ? Or how to tell the difference.


If it is encoder artifacts, does this mean that we are

at the mercy of lousy (and lossy) hardware at the broadcasting

stations ?


Thanks,

Peter