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Choosing a PJ

Discussion in 'Projectors, Screens & Video Processors' started by tazpc, Mar 3, 2004.

  1. tazpc

    tazpc
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    I would like to future proof as much as possible but have a couple of questions about resolutions of PJ's.


    1280x720 resolution PJ's should accept 720p input from an appropriate source.

    The data on a DVD is stored how??

    Does it have 720 lines of data or is the output using interpolated data?.

    IS analogue PAL and NTSC downconverted from the above?

    I'm confused:confused: :confused:

    Anybody enlighten me

    Thanks
     
  2. Gordon @ Convergent AV

    Gordon @ Convergent AV
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    1280 x720 resolution pj's will accept all sorts of resolution signals. 720P hopefully being one of them

    DATA on DVD is stored as MPEG2 compressed YUV 720x525 for R1 and 720x625 for R2.

    Not sure I understand the next question. Are you talkin gabout what they projector shows or what comes out of the DVD player?

    Analogue PAL and NTSC have same signal resolution specs as DVD.

    ie PAL is 720x625 whether it is out of a VCR or a STB or a DVD

    Gordon

    525 is vertical resolution more commonly known as 480 (which is the amount of actual picture info lines in the signal)

    625 is vertical resolution more commonly known as 576 (which is the amount of actual picture info lines in the signal)
     
  3. KraGorn

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    Not sure if I mis-read your question, Gordon took you to be asking about the way the data is stored ... perhaps you're asking whether it's interlaced or not (since you mention 720P right before and then ask about interpolation): it's interlaced, in common terms it's either 480i or 576i depending on video standard.

    The frames are rescaled as needed to fit the display device, yes at its' simplest it's done by interpolation. This re-scaling (and de-interlacing) can be done in the player, an intermediate signal processor or the display device (if digital and not a CRT, though CRTs also can take progressive input).
     
  4. tazpc

    tazpc
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    The query arose due to the new pioneer HDMI enabled DVD player used in conjunction with a pioneer plasma.
    Reputedly 720p output and input respectively.
    If using an HDMI enabled player on a suitable PJ (HDMI enabled)
    is the data being scaled to provide 720p from a PAL/NTSC DVD.
    ie is the data upconverted to 720p

    Cheers
     
  5. Gordon @ Convergent AV

    Gordon @ Convergent AV
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    taz: the data on a DVD is 720x576 (ACTIV) pixels. Anything other than this is scaled. So the answer is that the DVD player is de-interlacing to a 576Por 480P signal then re-scaling it to 1280X720. The Pioneer plasma's incidentally are 1024x768 and 1280x768 resolutions I believe.

    Gordon
     
  6. tazpc

    tazpc
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    Cheers Gordon.

    That answers my question but raises on more.
    My DVD collection is largely R1 NTSC

    Would the deinterlacing and upscaling work equally well for both PAL and NTSC

    or are we back to the perrenial NTSC vs PAL

    Have you any experience comparing the two when the have been upscaled.
     
  7. Gordon @ Convergent AV

    Gordon @ Convergent AV
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    In actual fact as Japan and US are NTSC countries and they make most of these devices you tend to find that the performance of de-interlacers is better with R1 material.

    Having said that there are lots of methods to do de-interlacing and probably even more ways of scaling so implimentation is what is important. Bad R1 will look worse than good R2.

    Scaled DVD can look superb when done properly.

    Gordon
     

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