component rca to bnc inut on PC monitor?

Discussion in 'DVD Video' started by Another Spellman Revision2, Jul 4, 2003.

  1. I want to connect my dvd player to my monitor, via the bnc inputs on the
    monitor. Problem is, the dvd player has Pb (blue), Pr (red) and Y (Green
    with sync) output. No H or V means that I cannot generate a signal
    acceptable by the monitor using the dvd player alone.

    So, my idea is to use my old PC to generate a H and V signal. I will connect
    a vga to bnc lead to the PC card output and connect the H and V bnc plugs to
    the monitor input and the three outputs from the dvd player to the R, G and
    B inputs on the monitor. Will this work? I'm thinking that I should set the
    monitor to sync on green - correct?

    Any idea how to determine what refresh rate I'll need to set my PC card to?
    I've assumed that it'll be 60Hz as that is what NTSC runs at. My plan is to
    create an mpeg file that is approximately 720 x 480 pixels, then run it in
    full screen mode to ensure the H and V output corresponds to that required
    by the DVD player.

    Is there any risk of damaging my monitor through this procedure?
    Another Spellman Revision2, Jul 4, 2003
    #1
    1. Advertising

  2. Another Spellman Revision2

    John Howells Guest

    "Another Spellman Revision2" <customer-serviceDELETEALLTHE CAPS AND SPACES
    TOO @sCAPS AND SPACESupanet.com> wrote

    > I want to connect my dvd player to my monitor, via the bnc inputs on the
    > monitor. Problem is, the dvd player has Pb (blue), Pr (red) and Y (Green
    > with sync) output. No H or V means that I cannot generate a signal
    > acceptable by the monitor using the dvd player alone.
    >
    > So, my idea is to use my old PC to generate a H and V signal. I will

    connect
    > a vga to bnc lead to the PC card output and connect the H and V bnc plugs

    to
    > the monitor input and the three outputs from the dvd player to the R, G

    and
    > B inputs on the monitor. Will this work? I'm thinking that I should set

    the
    > monitor to sync on green - correct?
    >
    > Any idea how to determine what refresh rate I'll need to set my PC card

    to?
    > I've assumed that it'll be 60Hz as that is what NTSC runs at. My plan is

    to
    > create an mpeg file that is approximately 720 x 480 pixels, then run it in
    > full screen mode to ensure the H and V output corresponds to that required
    > by the DVD player.
    >
    > Is there any risk of damaging my monitor through this procedure?


    Assuming you have correctly described the DVD output this does not stand a
    chance!

    First, the output you describe from the DVD is component, not RGB, so the
    three signals are not the blue, red, and green that a PC monitor expects.
    The Y ("green") is luminance (the B&W component) and the other two are
    colour difference signals. The page
    http://www.gregssandbox.com/gtech/movievideo/comp.htm shows how to create
    the Y, Pr (there called R-Y) and Pb (aka B-Y) signal from RGB, and you can
    work out similar equations to convert Y, Pr, PB to RGB (in typical text book
    style I leave this to the reader!).

    Second, the sync has to be *IN* sync! There is little chance that the sync
    signal from the PC will be in step with the picture from the DVD player.
    Even if the frequency were PRECISELY correct, which it has to be but will
    not be, it has to have frame and line pulses at PRECISELY the right moments,
    which they will not be. That's why it's called the sync signal, because it
    tells the receiver PRECISELY how to synchronize itself to display the
    picture properly. The sync source MUST start from the DVD player, however it
    may be processed along the way. Any old signal at about the right frequency
    just will not do!

    If you really want to connect the DVD player to the PC monitor you will have
    to get a Component to RBG converter. That will do the "sums" to convert the
    signal appropriately and generate the right sync signal. You might be able
    to find one at http://www.lektropacks.co.uk or http://www.keene.co.uk/, but
    the only ones I could see in a quick look converted component to a "TV" RGB,
    which has a composite sync (H and V on one lead), not the separate H and V
    sync a PC monitor usually expects.

    John Howells
    John Howells, Jul 4, 2003
    #2
    1. Advertising

  3. Another Spellman Revision2

    lash Guest

    "Another Spellman Revision2" <customer-serviceDELETEALLTHE CAPS AND SPACES
    TOO @sCAPS AND SPACESupanet.com> wrote in message
    news:...
    > I want to connect my dvd player to my monitor, via the bnc inputs on the
    > monitor. Problem is, the dvd player has Pb (blue), Pr (red) and Y (Green
    > with sync) output. No H or V means that I cannot generate a signal
    > acceptable by the monitor using the dvd player alone.


    Excellent way to get a psychedelic color job on your monitor! PC (VGA)
    CRT monitors accept VGA signals (R/G/B component video, + separate H,V sync
    as you noticed.) Nearly all DVD-players with component-video output will
    only output Y/Pb/Pr (Macrovision license prohibits unprotected RGB
    component video output, I believe.)

    As for the scan-frequency, a progressive-scan DVD-player's output is
    very close to VGA-frequency (33KHz for pscan/NTSC vs 31.5KHz for VGA.) Any
    modern multisync SVGA PC monitor will lock-on and properly display the
    signal (except for the color.)

    ....

    A handful of specialty (i.e. expensive) PC CRTs can accept Y/Pb/Pr in
    addition to the usual RGB VGA input.

    >
    >
    >
    > So, my idea is to use my old PC to generate a H and V signal. I will

    connect
    > a vga to bnc lead to the PC card output and connect the H and V bnc plugs

    to
    > the monitor input and the three outputs from the dvd player to the R, G

    and
    > B inputs on the monitor. Will this work? I'm thinking that I should set

    the
    > monitor to sync on green - correct?
    >
    > Any idea how to determine what refresh rate I'll need to set my PC card

    to?
    > I've assumed that it'll be 60Hz as that is what NTSC runs at. My plan is

    to
    > create an mpeg file that is approximately 720 x 480 pixels, then run it in
    > full screen mode to ensure the H and V output corresponds to that required
    > by the DVD player.


    No, the video-clock on the DVD-player and the PC must match perfectly. I.e.,
    they must be 'source synchronous.' What you're doing is running 2
    independent
    clocks separately, setting them to nearly identical nominal rates, and
    *hoping* they'll just happen to line up. You can try it, but the signals
    will drift over time.

    > Is there any risk of damaging my monitor through this procedure?


    probably not... For component Y/Pb/Pr, the signalling level is +/- 0.7vpp
    (on the Pb/Pr channels.) RGB VGA is +/- 1.0vpp, I think.

    If you're that desperate, you can get a 'transcoder' (RGB -> YPbPr.)
    Ask the folks over at www.avsforum.com -- transcoders are often needed
    for DVD-players to drive certain digital-projector systems (stupid ones
    with only RGB input, instead of Y/Pb/Pr. Or maybe it's the other way
    around...)

    ........

    in all honesty, it would be a lot *easier* to just buy a DVD-ROM drive
    for your PC. Then install a software (PC) DVD-player and use that
    program to watch the DVD on your PC-monitor.
    lash, Jul 4, 2003
    #3
  4. > Assuming you have correctly described the DVD output this does not stand a
    > chance!
    >
    > First, the output you describe from the DVD is component, not RGB, so the
    > three signals are not the blue, red, and green that a PC monitor expects.
    > The Y ("green") is luminance (the B&W component) and the other two are
    > colour difference signals. The page
    > http://www.gregssandbox.com/gtech/movievideo/comp.htm shows how to create
    > the Y, Pr (there called R-Y) and Pb (aka B-Y) signal from RGB, and you can
    > work out similar equations to convert Y, Pr, PB to RGB (in typical text

    book
    > style I leave this to the reader!).
    >
    > Second, the sync has to be *IN* sync! There is little chance that the sync
    > signal from the PC will be in step with the picture from the DVD player.
    > Even if the frequency were PRECISELY correct, which it has to be but will
    > not be, it has to have frame and line pulses at PRECISELY the right

    moments,
    > which they will not be. That's why it's called the sync signal, because it
    > tells the receiver PRECISELY how to synchronize itself to display the
    > picture properly. The sync source MUST start from the DVD player, however

    it
    > may be processed along the way. Any old signal at about the right

    frequency
    > just will not do!
    >
    > If you really want to connect the DVD player to the PC monitor you will

    have
    > to get a Component to RBG converter. That will do the "sums" to convert

    the
    > signal appropriately and generate the right sync signal. You might be able
    > to find one at http://www.lektropacks.co.uk or http://www.keene.co.uk/,

    but
    > the only ones I could see in a quick look converted component to a "TV"

    RGB,
    > which has a composite sync (H and V on one lead), not the separate H and V
    > sync a PC monitor usually expects.
    >
    > John Howells
    >
    >


    Many thanks for the reply!

    As with most things in my life, I'm most wrong about something when I feel
    I'm halfway right.
    Another Spellman Revision2, Jul 4, 2003
    #4
    1. Advertising

Want to reply to this thread or ask your own question?

It takes just 2 minutes to sign up (and it's free!). Just click the sign up button to choose a username and then you can ask your own questions on the forum.
Similar Threads
  1. John

    BNC Cable Question

    John, Oct 15, 2003, in forum: Computer Support
    Replies:
    6
    Views:
    428
  2. nick
    Replies:
    0
    Views:
    1,308
  3. sams
    Replies:
    3
    Views:
    6,617
    Oldus Fartus
    May 31, 2004
  4. Replies:
    1
    Views:
    3,049
    Jeff Rife
    Dec 2, 2005
  5. Stereo Cassette Deck

    WTB: 15 pin VGA to 4x BNC video cable

    Stereo Cassette Deck, May 14, 2004, in forum: NZ Computing
    Replies:
    13
    Views:
    861
    -=rjh=-
    May 28, 2004
Loading...

Share This Page