Do I need 3:2 pulldown?

Discussion in 'Archived Threads 2001-2004' started by Kevin_Cas, Jul 30, 2002.

  1. Kevin_Cas

    Kevin_Cas Agent

    Jul 20, 2002
    Likes Received:
    I have decided to pair my Toshiba 5700 progressive-scan DVD player with a Samsung TXM-3296HF. One of the main drawback to this set is that it lacks internal 3:2 pull-down processing. However, my particular model DVD player has it(as well as aspect ratio control), so do I really need it on the TV? Dosen't the DVD internal 3:2 procesing supercede the TV's and provide the same benifits? Also, what other types of sources can take advantage of 3:2 processing? As I understand it(correct me if Im wrong, of course) 3:2 processing is employed to provide a more "film-like" picture on a video display by taking down the refresh rate(or something) for the 24fps of film. Since TV is broadcast in 30fps, is TV internal 3:2 only to the advantage of interlaced players? Right now, I only plan on hooking up a DVD player and videogame systems(PS2, X-Box, Gamecube) to the TV. Later on, I will buy an HDTV tuner, or rent one from my cable company. When a movie or TV show is broadcast in HDTV(such as HBO of Showtime HD, for example), will it be shown in 24fps? If so, will my picture be of a lesser quality due to my TV's lack of 3:2?
    I know I'm allover the map, but any information anyone can provide me with would be greatly appreciated. Thanks in Advance!
  2. Vince Maskeeper

    Vince Maskeeper Producer

    Jan 18, 1999
    Likes Received:
    1) If you feed the TV a 480p signal from the dvd player- all the processing, including 3:2 pulldown will be done by the dvd player. The majority of sets completely bypass any additional scaling or changing of material fed to it via the progressive component inputs. The internal line doubler systems on TVs (which the majority suck anyway) will only be used on standard NTSC type 480i sources (VHS, Cable, Etc).
    2) 3:2 pulldown basically fixes an issue related to using a line double on 24 frame film transferred to video. When 24 frame film is done on video, certain frames are repeated in a mathematical order to make the 24 frames fit in the 30 frame requirement for video. When a line double attempts to merge these frames back into a progressive sequence- it needs to use a different sequence with film source material than it does with video... or else it will end up merging frmaes that shouldn't be merged.
    Basically, without getting over technical- In a film source video feed: two video frames right after each other will often contain images from different film frames. If these are merged into a single frame, as a line double does, This often creates a weird artifacting issue (especially if there is motion). You basically create a jagged frame because it's ever other line of 2 different frames put together...
    In the best of laymans terms, 3:2 pulldown allows proper reconstruction of interlaced frames so that not only is a new progressive frame created, it is the correct new frame and the extra unneeded half frames are discarded.
    Without 3:2 pulldown, often a doubler will create a single progressive frame by merging 2 half frames containing 2 different images, creating a bad combing effect.
    Imagine for a second a single frame which is actually made up of 2 different images. The even lines are of one frame and the odd ones of another. If this were to happen during a panning scene, you would have half the picture being one part of the pan, while half would be from a split second later. It ends up looking something like this:
    There are several explanations here on the forum, and on several websites- these might help...
    3) For HD content, you won't need to worry about the 3:2 pulldown issue- as the actual frame rate for HDTV allows for raw direct 24 frame material- and it will be formatted accordingly. You TV's internal scaler (which would be the part that would execute 3:2 pulldown if you needed it) will only be in effect for standard definition NTSC type signals... So for DVD, the deinterlacing and pulldown will happen in the player. For video games, the deinterlacing will happen in the TV and pulldown shouldn't be necessary, for HDTV there will be no deinterlacing- and the frame rates will be correct from the source.
    Hope that helps

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