Component question

Discussion in 'Displays' started by Sacha_C, Oct 13, 2003.

  1. Sacha_C

    Sacha_C Second Unit

    Joined:
    Jan 13, 2003
    Messages:
    294
    Likes Received:
    0
    Is component exactly the same signal as comes out of a video card's VGA port but with different connectors?

    Do they both support the same resolutions? Are there any differences besides the connectors?

    Thanks
     
  2. David Abrams

    David Abrams Stunt Coordinator

    Joined:
    Jan 20, 2001
    Messages:
    94
    Likes Received:
    0
    Sacha,

    Component video is the same signal that comes out of a video card's VGA port, but it may not be the same type of component. There are many different formats that can be referred to as component video. I believe that you are asking about the most common Y Pb Pr type component video (this comes from a DVD Player). Depending on how the computer and video card is configured you can get this signal out of a VGA output; however, most VGA outputs from computers are RGB component video. They can also output other formats of RGB such as RGBs and RGBHV.

    The resolutions on computers and video cards are usually variable whereas most DVD players it is generally fixed.

    Regards,
     
  3. Allan Jayne

    Allan Jayne Cinematographer

    Joined:
    Nov 1, 1998
    Messages:
    2,404
    Likes Received:
    0
    It is possible for VGA and Y/Pb/Pr to exist in compatible "resolutions" aka "scan rates" but they normally do not come that way.

    The closest they come is "regular VGA" which is 640 x 480 @ 60 Hz non-interlaced and "progressive scan component video" which is 480p.

    Differences: Regular VGA (I think) is 60 Hz whereas 480p is 59.95 Hz (frames per second), although many TV's/monitors and PC's/DVD players' don't care.

    The color ranges represented by the three signal cables of VGA (and all forms of RGB) are red-black, green-black, and blue-black while for Y/Pb/Pr they are roughly red-cyan, white-black, and blue-yellow.

    VGA has a fourth and fifth cable(s) for sync. while Y/Pb/Pr component video has the sync combined with the Y. RGB is also commonly encountered with the sync. combined with the G.

    What happens after the end of one scan line and the beginning of the next is slightly different although many TV's/monitors and PC's/DVD players don't care.

    There are several situations where Y/Pb/Pr is converted to computer resolutions such as 800x600, 1280 x 1024, etc. but only rarely is computer VGA video converted to TV resolutions such as 1080i (1920 x 1080 interlaced).

    More:
    http://members.aol.com/ajaynejr/compon.htm
     
  4. Sacha_C

    Sacha_C Second Unit

    Joined:
    Jan 13, 2003
    Messages:
    294
    Likes Received:
    0
    So those VGA to component adapters have circuitry inside and arent just an adaptor?

    Thanks
     
  5. Allan Jayne

    Allan Jayne Cinematographer

    Joined:
    Nov 1, 1998
    Messages:
    2,404
    Likes Received:
    0
    Yes, circuitry is needed. That part of the circuitry that changes from one resolution to another is called a scan rate converter or scaler. That part of the circuitry that changes from RGB to Y/Pb/Pr or back is called a colorspace transcoder.
     
  6. Sacha_C

    Sacha_C Second Unit

    Joined:
    Jan 13, 2003
    Messages:
    294
    Likes Received:
    0
    "colorspace transcoder"

    Sounds like its from star trek or something [​IMG]
     

Share This Page