Macroblocking

Started by hidefbob Jun 28, 2005 3 posts
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#1
Why is it that some sports in HDTV are subject to macroblocking and others are not?

I have watched sports in 1080i and seen macroblocking numerous times when the camera is panning. I have particularly noticed this when a player is moving close to the camera and the camera is panning.

However, on other occasions I have watched sports in 1080i and seen no macroblocking. The camera pans and the background remains absolutely clean.

I have even noticed this difference when watching different games broadcast by the same station. WGN HD's broadcasts of the Cubs are usually free of macroblocking. But the odd time I have seen a game where it has been an issue.

I used to think it was an MPEG2 compression issue. However, if that were the case why is not macroblocking an issue on every game I watch?
#2
If this is not via OTA the reasons are numerous and all deal with bit shaving.

What is your HDTV source?
#3
I haven