Funny TV color.

edited August 2003 in Hardware
A friend of mine has an ATI 8500 AIW hooked up to his TV (the vid card does the tuning, and outputs to the TV. His picture's color looks.... a bit washed out, almost hard to describe, really. We tried messing with it using both vid card and TV software settings, and couldn’t get the colors to look "right" when compared to a TV.


Now I get home, and use my Ti4600's composite input from a VCR (that's my TV tuner) and the colors have that same funny look to them, and a half hour of messing with all the controls, and comparing it with a TV, I get no-where closer to making the colors look "correct". I'll post a color bar test which a station is currently broadcasting (It's almost 3 AM here).

Now the colors (on a real TV) look more distinguished. The two rightmost bars appear to be nearly white, while the bar to the far left is a very dark green (but not black). Each bar has clear lines distinguishing the colors.

I should mention, I am no pro photographer, and while this IS a very good digital camera, it cant seem to take a perfect pic of a TV's image.
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Comments

  • edited August 2003
    Now after being processed by the vid card (doesn’t seem to matter what brand, or type of tube receiving the output apparently. Everything looks muddy. Notice the green colors look "browner".

    Anyone have any ideas why this is/how I could fix this? This is the sorta stuff that drives me up the wall after awhile.
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  • SouriatSouriat Nottingham, UK
    edited August 2003
    I get slight off colours too, mostly green for me but blue is normally a bit dull. I just tend to sit around and play with the colour controls in the nvidia display settings for the TV untill they pretty much match my monitor's colours.

    Other than that ive not managed to find a way to make any changes to the way the vid card output looks on my TV.
  • danball1976danball1976 Wichita Falls, TX
    edited August 2003
    Maybe the red and blue wires on the cable are bad.

    I connected my PNY GeForce 4 Ti4200 to my 27" JVC TV, and I first got the color bars when I turned the TV to the SVideo input, and they were the correct colors.
  • danball1976danball1976 Wichita Falls, TX
    edited August 2003
    Forgot to post this. These are the settings, I left them at default.
  • edited August 2003
    I messed with those settings, Dan, along with the settings in the app I use to watch the vid input. Using either/combo of both I still cant get it right.

    Also, I use the composite input to my comp as my VCR wont output SVideo, also I'm using high quality AV cables (or better than what I'd use otherwise anyways).
  • edited August 2003
    Just noticed something:

    Have you ever tried to back up a movie on VHS.... from a rental... and find that the copy's color/brightness fluctuates thanks to copy protection?

    Well, that’s exactly what Family Guy was doing.
  • SimGuySimGuy Ottawa, Canada
    edited August 2003
    You could try a little program that I found that provides better support for NVidia-based video cards.

    TVTool 8.2.5

    With the contrast rising up and down like you have suggested, you might be wise to try disabling any DVD recording/playing software you have installed, as that could cause the effect that you are mentioning. :)
  • EnverexEnverex Worcester, UK Icrontian
    edited August 2003
    TheSmJ said
    Just noticed something:

    Have you ever tried to back up a movie on VHS.... from a rental... and find that the copy's color/brightness fluctuates thanks to copy protection?

    Well, that’s what Family Guy was doing exactly.

    I get what looks like a video going in and out of the correct tracking when I try to save to a VCR from a DVD, which is the infamous Macrovision kicking in, but never actually tried VCR to VCR recording (Even though we have loads of VCRs, just could never be bothered). Its weird how it knows when you start recording though, as soon as you press record, it starts fading in and out :shakehead

    NS
  • edited August 2003
    Actually it seems the latest WDM drivers from nVidia are giving me much better picture, and the macrovision copy protection is gone!

    I'll try it again tonight to make sure it wasnt just my wishfull thinking.
  • DexterDexter Vancouver, BC Canada
    edited August 2003
    The problem you are seeing with the colours is due to the colorspace conversion from TV world to PC world. As you probably know, TV's use NTSC colour (National Television Standard for Color - or as many broadcast people will call it - Never The Same Color), or in Europe and Asia, there is PAL (Phase Alternating Line.) Your PC uses the RGB colorspace. When you use a TV Tuner card in North America, you are capturing an NTSC signal with the card, but displaying it on an RGB monitor. Inevtiably, some color changes are going to occur.

    A few things you can do:

    - Does your control panel allow Gamma Correction? My Nvidia driver here at work has a simialr control panel to Danball's. If you adjust the Gamma settings only, you will phase shift the whole colour display. But you can also selectively adjust the Red, Green or Blue channels. If you notice your colour problems are more pronounced in one part of the spectrum, adjust the appropriate channel only.

    - Does your monitor allow you to set Colour Profiles? This allows you to set the overall colour of your monitor based on what type of display you will be doing. Digital Video editors and print graphics artists will set their monitors to the right profile for their environment, so that their on-screen work will closely resemble what their finished product looks like on their final medium. If you have the ability to set profiles, choos an NTSC profile when you wish to view TV on your monitor (may require a reboot to load.)

    In regard to the Macrovision problem, there are a few things you can do, but a brief explanation of Macrovision is in order. Macrovision copy protection works by embedding a cyclical frequency into the audio. It is pitched so as to be unheard by human ears. Electronics producers have been forced, bullied and regulated into placing circuitry in their recording equipment (VCR's and computer capture cards) which detect this frequency. The frequency is then shunted over to the video recording circuitry. The fading in and out that you see is in direct relation to the audio frequency rising and falling. The display circuitry does not detect Macrovision, so you can always watch something. But if you push record, your display shows the signal downstream of (AFTER) the record circuitry. Hence, the comment :
    Its weird how it knows when you start recording though, as soon as you press record, it starts fading in and out
    It doesn't. But your display automatically switches the signal through the record circuitry first, then to the output circuitry, so your output is now directly affected by whatever happens to the signal in the record circuitry.

    But, no system is foolproof. :D

    If you are using an external DVD or VHS player for playback, you can hook a Macrovision filter up to the input cable. This filter masks out the Macrovision frequencies. Cheap ones may cause the video to look slightly "washed out" (lose a bit of colour.) But I have seen $50 ones that work great.

    If you are using a DVD ROM with DVD playback software, there are also sharware DVD players which will mask out Macrovision digitally, resulting in perfect "archiving" of your DVD titles.

    Just do a Google for macrovision filter or video enhancers to do some research.

    Bear in mind that any recording of copyright protected media other than strictly for the use of archiving is illegal, immoral and will cause you to roast in Hades for eternity if Interpol or the FBI catch you....:eek3:

    Dexter...
  • danball1976danball1976 Wichita Falls, TX
    edited August 2003
    TheSmJ said
    Just noticed something:

    Have you ever tried to back up a movie on VHS.... from a rental... and find that the copy's color/brightness fluctuates thanks to copy protection?

    Well, that’s exactly what Family Guy was doing.

    If you ever played a tape from the very beginning, where it is still black, and you have the volume up high enough, you can hear a code. This is the code that is designed to confuse the recording circuitry. This code occurs on copy protected tape.

    My JVC VHS/DVD combo allows copying DVD's to VHS tape, but of non copyprotected material only.
  • edited August 2003
    Well I already knew what macrovision was, but that was still a very interesting read.

    What I don’t understand is if this is being broadcast. I had originally thought it was only used on storable media (such as DVDs and VHS).

    Also, it's kinda hard to tell what’s going on now. While the picture is much better with these new drivers (thanks for the news post Spinner) occasionally (much, much less often) visual issues still do show up. Interestingly enough, it seems to happen when most of the screen is white, during both shows and commercials.
  • DexterDexter Vancouver, BC Canada
    edited August 2003
    Macrovision is not used in broadcast, only on recorded visual media (DVD, VHS.)

    Sounds like your cable signal may be a bit strong. Sometimes if someone has a strong signal, and their is a lot of white in the image, or very bright yellow / reds (high chrominance values) they might notice that their TV buzzes. This is because the colour signal values don't clamp off at 100%, instead they bleed over to other parts of the signal (brightness, audio, etc.) In the PC world, tuner cards won't buzz as badly as TV's will, but they will make the signal go a soft white all over.

    Do you ever see buzzing problems on your regular TV set? If so, and you cannot adjust the settings well enough on your PC card, ask the cable company to come measure your signal strength to see if it needs an adjustment.

    Also, if you have the cable in directly to the PC, try running the cable first through the TV or a VCR, then taking the pass-through out into your PC. This may allow enough of the signal to bleed off first, giving you a weaker, more manageable signal.

    Dexter...
  • EnverexEnverex Worcester, UK Icrontian
    edited August 2003
    Old consoles were a major problem for the buzzing, especially on old TVs.... used to drive me mad, always wondered what caused it though, as it's really loud when using an Amiga on a TV, remember it was quite annoying on my Playstation too, though again, it depended on the TV moreso....

    NS
  • DexterDexter Vancouver, BC Canada
    edited August 2003
    NightShade737 said
    Old consoles were a major problem for the buzzing, especially on old TVs.... used to drive me mad, always wondered what caused it though, as it's really loud when using an Amiga on a TV, remember it was quite annoying on my Playstation too, though again, it depended on the TV moreso....



    It's Radio Frequency (RF) bleeding from the video signal to the audio signal. If the video signal is too strong (white is too bright, chroma values too high), it generates higher amplitude RF. This stronger RF signal bleeds from the video signal to the audio signal. Newer TV's have better processing to help eliminate that.

    Dexter...
  • edited August 2003
    Well I already run the video through a VCR first. As for the cable strength, I'll have to check some things. Being as we are in a rather close proximity to channel the channel 4 and 7 broadcasting station, we already get double images on out cable (one from broadcast, the other from cable). We believe there is a leak in the cable's grounding somewhere in the house, but obviously that would take some time to find. We also have a cable amp as well... I wont go into details but the house's wiring is a mess when it comes to cable.

    BTW, the rest of the TVs in the house are fine. Only the computer (which is tuned from a VCR).
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