the dreaded CHROMA BUG; do I have it?

Discussion in 'Archived Threads 2001-2004' started by JeremyX, Dec 14, 2002.

  1. JeremyX

    JeremyX Stunt Coordinator

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    Well I just got the new Sony S50ES integrated DVD/receiver. And whenever I see bright reds or blues it is very, very pixelated....is this the chroma bug? I have seen it in at least 3 movies.
    What's more, I have seen a visible, slim, band of discoloration at the top and bottom of letterboxed movies...is this part of the chroma bug, or something else?
    Is there a fix for this? Or do I need to buy a different DVD player?
    Thanks in advance.
    [​IMG]
     
  2. Allan Jayne

    Allan Jayne Cinematographer

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    The chroma bug is most often noticed as thin slivers of the wrong color at the top of bottom edge of a color patch or at a diagonal color boundary. It gives diagonal boundaries a ragged appearance.
    A thin band of discoloration at the top or bottom of a letterboxed movie can be the result of the chroma bug. It can also be the result of poor de-interlacing (if you use progressive scan), a poor comb filter (if you use a composite cable connection), a deficiency in the DVD player downconversion (if you choose "4:3 letterbox" for "TV shape"), a defect recorded on the DVD, or misconvergence in the TV.
    If your player has the chroma bug, there is nothing you can do to fix that player.
    Pixellation in general is not the chroma bug but it can represent another, systematic, shortcoming of your player. Sometimes a player literally cannot keep up with processing the video data stream from the disk when there is lots of subject motion. THe player is "forced to choose" between incomplete processing of selected parts of the picture and keeping on going (pixellation) or failing to finish making one video frame and starting the next (tearing).
    All current DVD's use compression of the video, using one or more of the Motion Pictures Experts Group (MPEG) encoding standards. I haven't seen it myself but some experts claim that the finite number of shades (gradations) available for colors together with the compression leads to noticeable random grainy irregularity within solid color patches that usually keeps changing for each different video frame e.g. 24 times a second, sometimes referred to as "crawlies on the wall in the background".
    Poorly produced DVD's can have pixellation. This was a problem in the very early days of DVD. Do you have another DVD player where you could compare the picture for pixellation?
    More:
    http://members.aol.com/ajaynejr/vidbug2.htm
     
  3. JeremyX

    JeremyX Stunt Coordinator

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    Hi,

    Thanks for the great info. Unfortunately don't have a backup DVD player to test...but I will get one today and test it out..what a shame, this is a newly released DVD player too..and not cheap at all.
     
  4. Kevin P

    Kevin P Screenwriter

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    If your TV is not properly calibrated, particularly if your contrast or sharpness is set too high, MPEG artifacts that are normally invisible may become visible. This may appear as pixelation, especially on static backgrounds.

    Try calibrating your TV with AVIA or Video Essentials and see if that helps.

    KJP
     
  5. Bob Saylor

    Bob Saylor Stunt Coordinator

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    Kevin is right. Make sure you don't have your settings too high on your TV. It can make a difference.
     
  6. Hank

    Hank Guest

    Sony & Toshiba were known for the 'chroma bug' in past players. I would be surprised if your new Sony has it.
     

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