1. I'm a little confused about Prog video vs. 3:2 pulldown.

    I recall reading they are separate functions and have only a basic understanding of what's involved.

    So...do Prog players automatically do 3:2 pulldown correction for a more film-like cadence?

    I'm wondering because 3:2 correction is most often advertised as an internal function of TV deinterlacers with little said about DVD players.
     
  2. Don_Berg

    Don_Berg Supporting Actor

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    The telecine process is used to convert FILM sources that were originally progressive 24frame/sec to interlaced 60fields/sec video. 3:2 pulldown in a de-interlacer is used to reverse this process and the progressive DVD player in 480p format then outputs 60 progressive frames/sec by duplicating each of the film frames in a 2,3 alternate fashion.

    The better de-interlacers (like Faroudja) automatically look for the 3:2 cadence and if detected use 3:2 pulldown to de-interlace, if not they switch to a different mode for interlaced 60field/sec video. The better de-interlacers go thru a more involved process for de-interlacing true interlaced video material since alternating fields may not with each other with motion - they were captured 1/60sec apart. Cheaper de-interlacers will just use only one field and reduce the vertical resolution by 1/2 causing a lot of jaggies.
     
  3. Brian L

    Brian L Cinematographer

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  4. Allan Jayne

    Allan Jayne Cinematographer

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    The best progressive DVD players have all three, selected automatically -- 3-2 pulldown sensing from flags inthe video data as a first choice, then cadence reading when the 3-2 pulldown can be sensed by analyzing the video but the flags were wrong, and motion adaptive video mode de-interlacing. The latter mode weaves in bits of scan lines from the next field for stationary subject matter while interpolating bits of scan lines from the neighbors for moving subjects. (Not weaving the entire screen or interpolating the entire screen.)

    The worst progressive DVD player I heard of, a Pioneer 434, I am told has none of these three methods. Ihaven't auditioned one but it probably does nothing more than take single fields and interpolate the intervening lines, resulting in more jaggiesand a softer picture.

    The best progressive scan in TV sets includes both 3-2 pulldown sensing using cadence reading, and motion adaptive video mode, selected automatically perhaps several times a second.

    More:
    http://members.aol.com/ajaynejr/viddoubl.htm
     

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