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Chroma bug - is it in the mpeg decoder or deinterlacing stage?

Discussion in 'Blu-ray & DVD Players & Recorders' started by cybersoga, Jul 9, 2003.

  1. cybersoga

    cybersoga
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    I was wondering if the chroma bug (where the edges of red objects look pixellised/streaky compared with the rest of the picture) was due to the mpeg decoder in the dvd player or the deinterlacing stage (in my case in the TV)?
     
  2. Urotsukidoji

    Urotsukidoji
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    I don't think its in the deinterlacing stage as it can occur with an interlaced signal such as sky. I saw it on my 100hz rear projection set with sky before I upgraded to sky+ which has less worse chroma bug.
     
  3. cybersoga

    cybersoga
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    I think you might be right, I never really noticed it while watching TV from the Netgem box. If its in the mpeg decoder, shouldn't the problem also affect interlaced TVs?
     
  4. StooMonster

    StooMonster
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    Chroma bug is an error in MPEG2 decoders, as identified by this very board's RichardA (Richard Ansell of Snell & Wilcox).

    Check out the old favourite here, although mostly about DVD players and PC based players it is equally as true for Sky digital's MPEG2 decoder.

    There are two types of "chroma bug": Chroma Upsampling Error (CUE) and 4:2:0 Interlaced Chroma Problem.

    StooMonster
     
  5. cybersoga

    cybersoga
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    I have read that before, but not recently - thanks for finding it again. So the solutions are - a dvd player that decodes properly (the preferable option, makes no difference if it has progressive scan outputs) or a chroma filter in the deinterlacer (whether that's inside a progressive scan dvd player or external) which just "smooths" the problem rather than fixing it.

    So CUE should be visible on interlaced TV's aswell?

    I really wish Sony would fix their mpeg decoders...
     
  6. Urotsukidoji

    Urotsukidoji
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    Yes, my 100hz toshiba rear projection tv displays the bug.
     
  7. AOD

    AOD
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    So does my Sky digibox.

    It's painfully obvious when watching something like the intro sequence to Angel and the name comes up in red. Ugh!
     
  8. Urotsukidoji

    Urotsukidoji
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    Agreed. I was very pleased to find that the bug was much reduced when I upgraded to sky+. It was truly awful with my very early model pace box.
     
  9. Nic Rhodes

    Nic Rhodes
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    Nice answer SM :)
     
  10. StooMonster

    StooMonster
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    Cheers Beekeeper.

    I too have Sky+ but I am not convinced it's less than my old Sony digibox. However, Sky+ is on my plasma via iScan Ultra which filters out chroma problems. :) And old Sony box is on my LCD that I sit (or lay in bed) far enough away from, so don't see it. But when I do get up, it hits in the face like an AV equivalent of the tango man.

    StooMonster
     

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