DUMB question sorry - HDTV polygons!?

Discussion in 'Beginners, General Questions' started by Denny_Z, Jul 2, 2003.

  1. Denny_Z

    Denny_Z Auditioning

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    Hi All, pardon the stupid questions, but I'm new here and I honestly tried searches and could not find the answer. Anyway, I just got COMCAST HDTV hooked up yesterday. I have a RPTV HD TV. When I watch a few of the HD channels, which look amazing I have to say, sometimes when there is a lot of movement in the video the picture becomes "pixelized", where I just see a bunch of tiny squares, like the kind you see when a digital video signal is losing strength. But then when the scene slows down, the pictures clear up and are super crisp again.

    What is this phenomenon and how can it be fixed?

    Many thanks!
     
  2. Allan Jayne

    Allan Jayne Cinematographer

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    There are numerous places where this macro pixeling can take place, but the underlying reason is inssufficient data or insufficient time to process the data.

    Material is often compressed a lot to put on satellite and cable channels, and this may result in loss of information particularly in areas with lots of fine detail and lots of motion.

    If there is a transmission error, a part of the picture may be lost and end up having macro pixels stuffed in it.

    If the HDTV tuner box is of inferior quality, it cannot process the video data fast enough, and rather than add unnatural and incorrect slowdown to the motion utnil it catches up, it just fails to finish the fine detail and stuffs macro pixels in instead. (This problem can also occur earlier in the video production and transmission process where you can't do anytyhing about it.)

    Video hints:
    http://members.aol.com/ajaynejr/video.htm
     

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