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There is no such thing as PAL progressive scan!

Discussion in 'Projectors, Screens & Video Processors' started by bonzobanana, Aug 9, 2003.

  1. bonzobanana

    bonzobanana
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    It just seems to me stupid saying a dvd player has PAL progressive scan when the word 'PAL' stands for phased alternate line. PAL actually means interlace. So having PAL progressive scan is a contradiction in terms. Where as NTSC stands for national television standards committee and there is no problem with calling that progressive. I mean you wouldn't describe something as stereo mono sound or black and white in colour etc.

    Still I suppose we are stuck with it now.
     
  2. hornydragon

    hornydragon
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    What wouls you suggest it is labled then??????
    50HZ Progressive Scan Video is the closest you can get whilst being consumer friendly

    Why do manufactuires call copmosite video PAL when RGB is still a PAL signal?
     
  3. bonzobanana

    bonzobanana
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    Its funny when you come to fhink of it, NTSC is a PAL signal (phased alternate line). NTSC RGB is therfore a PAL signal. But PAL isn't a NTSC signal. Progressive NTSC isn't a PAL signal though. I'll get my coat.
     
  4. Gordon @ Convergent AV

    Gordon @ Convergent AV
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    RGB is not a PAL signal.

    Composite video is a signal type and PAL is a signal standard that can be sent as either composite or s-video(s-video is a component video signal)

    The correct nomenclature is 576P50Hz it can be in many formats of course, YPrPb, RGBS, RGBHV.....
     
  5. RichardA

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    NTSC most certainly could not be called PAL !!!

    Phase Alternate Line indicates that the phase of the U signal inverts on each line creating the automatic phase error cancelling that prevents unwanted chroma phase shift.

    This is the element missing from NTSC that often means that it gets calles 'Never Twice Same Color'

    As Gordon mentioned PAL and NTSC only relate 'officially' to Composite and Y/C signal formats.

    The 480P and 576P terms would actually refer to a component (Y,Pr,Pb) type format as this is the only format used for HD.

    There is no 'official' name for Progressive scan 525 line or 625 line signals over RGB as this implies a computer type standard - though 480 lines Progressive scan is the same timing as VGA, there are more horizontal pixels in the video signal than in a VGA signals (720 pixels versus 640). Also it's worth remembering that PC type signals assume square pixels, whereas Video signals are not usually square.

    Hope this helps clarify things :zonked:


    Richard,

    In Hollywood :p
     
  6. MartinImber

    MartinImber
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    My pet hate is stereo described as NICAM

    On NTSC TVs, DVB-T TVs:rolleyes:

    The correct term is stereo:lesson:
     
  7. LV426

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    Like so many terms, their original meaning gets diffused over time. Whilst, by its strict definition, PAL means, as you say, Phase Alternate Line (which is a colour carrier mechanism more fully described by Richard A above).......its colloquial meaning has tended to degrade to mean, a 625-line, 50hz TV signal with a PAL colour carrier. This is not accurate - PAL can equally be 525/60 or, presumably, anything else. Nevertheless, it is often used to imply a line and field structure as well. In this (inaccurate) context - PAL progressive is, indeed, a meaningful concept.

    BTW - do you ever refer to a vacuum cleaner (made by, say Dyson) as a 'Hoover? Or the action of using one as 'hoovering'? Or a ballpoint pen (made by Papermate) as a Biro? etc?

    At the end of the day, the purpose of language is to convey meaning; there are probably very few people in England who would not understand what you meant by 'Hoovering'.......
     
  8. bonzobanana

    bonzobanana
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    Not sure whats going on here but surely the definition of 'phased alternate line' is simply an interlaced screen. How can you get the information regarding the u signal from PAL. My understanding is;

    Phased (as in something which your building in stages. You plan to build a housing estate but you build four houses at a time so the development is phased. In this context you are building a screen image but the image is phased in two parts (fields).

    alternate (as in not every line but instead a gap between every line).

    Line (as in the horizontal lines going down the screen)

    How can the single word alternate mean what you say? It seems to me you are defiining the actual PAL television standard which is not what this thread is about. Its about what the definition of PAL means and it means an interlace broadcast standard. Just as a dvd may be a collection of binary information forming large mpeg files etc but dvd actually means 'Digital Versatile Disc'

    If you honestly think phased alternate line means what you say then break it down with your own definition for each of these 3 words?
     
  9. calscot

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    From www.dictionary.com...

    Phase:
    The fraction of a complete cycle elapsed as measured from a specified reference point and often expressed as an angle.

    Alternate:
    Designating or relating to every other one of a series.

    Line:
    One of the horizontal scans forming a television image.

    So "alternate line" is explained but the phase part is a trifle ambiguous. I would assume that the phase of the signal will change 180 degrees on each alternate line which could indeed cause some errors to cancel each other out.

    Cheers,
    Cal.
     
  10. kevenh

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    It's not 'phased' it's 'phase'

    so Richard and calscot have explained it.

    NTSC was 1st, and has problems with phase errors in the colour after transmission.

    PAL is similar to NTSC but being developed later was able to include a 'fix' for the colour phase issue - alternate the phase of the colour subcarrier.
     
  11. RichardA

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    Bonzobanana,

    Choosing irrelevent analogies to words does not re-define the meaning of PAL, and it can only mean one thing.

    Calscot has the definition for each word, with the phase element refering to the phase of the subcarrier signal representing the U axis which swings through 180 degrees phase shift relative to burst.

    I don't feel I have to justify to you the definition chosen by the EBU etc... to reflect a standard (and it is a standard, so the meaning is defined quite clearly) so I won't bother to reply again
     
  12. bonzobanana

    bonzobanana
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    Ok sorted it now in my brain. Still sounds like its referring to interlace but realise it isn't.
     

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