Suggestion for "top of screen interference"

Discussion in 'TiVo Series3 HDTV DVRs' started by MScottC, Oct 5, 2007.

  1. MScottC

    MScottC Well-Known Member

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    Sep 11, 2004
    This is based on a prior thread, but I thought it an important enough issue to create its own thread so that the powers that be at TiVo will see it. I, like many others run my HDTV at 1:1 pixel mapping for a sharper image. This, however, is akin to what we video professionals call "underscan" on video monitors, allowing us to see the entire raster. As many of us have noticed, very often Vertical Interval Timecode or Closed Captioning, or other broadcast data is visible when viewing SD material that is resampled up to HD in either the 1080i or 720p fixed modes. All TiVo really needs to do is to somehow crop the two 2-3 lines of those images and that annoyance will be gone. There is nothing visually important up there, as every professional TV production person in the world knows not to use the outer 5% of the screen for anything important. My guess, and without a waveform monitor at home. is that all TiVo needs to do is crop out all the lines up to line 21, which is the first line of actual visual content, though a crop to line 23 would safely deal with some of the variances in vertical delay or misplaced data.
     
  2. bkdtv

    bkdtv New Member

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    If they crop, the signal will no longer be a valid ATSC resolution. I assume you mean some kind of black overlay.

    There is the question of how that will effect PQ. First, the high-definition video processing in these solutions is not particularly robust. Second, it's not clear how such an overlay would affect the deinterlace capabilities of some newer TVs. Would you want a black strip across the top and bottom if that dropped you out of 1080p film deinterlace mode and into ~900p effective motion-adaptive video deinterlace mode?

    Of course, if they make this feature optional under Video Settings, then the customer could decide whether they want to use it or not.
     
  3. sfhub

    sfhub Well-Known Member

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    Jan 6, 2007
    Are you sure it is still line 21 after the network scaled it to 1920x1080 and sent it to TiVo as 1080i?

    To me, this sounds like a feature that is more appropriately implemented in the display and final processing prior to display.

    I would also think people should complain to the broadcaster to reconfigure their equipment so everybody benefits.
     
  4. MScottC

    MScottC Well-Known Member

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    You know, it could be I'm seeing this on SD upressed by certian station, so perhaps it is poor upressing choices by certian HD broadcasters. Whatever, these signals are making into the HD lines that are not intended to be visible.
     
  5. Joybob

    Joybob New Member

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    Oct 2, 2007
    This issue has already been resolved. Either switch to Hybrid/Native mode or get used to that little line of pixels.
     
  6. zaknafein

    zaknafein Shorthanded

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    Kansas City, MO
    I agree. This isn't TiVo's problem, this is the broadcaster's problem. I'd rather TiVo not be matting any part of the image before it sends it to the display.
     
  7. MScottC

    MScottC Well-Known Member

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    Sep 11, 2004
    That is NOT "resolved." That is "compromised." Assuming that the data is in the correct place on the SD image, it is being re-mapped in the uprez to the incorrect place on the HD raster. They should be re-mapped to the Vertical Interval area of the HD signal, not to lines that are intended to be viewed. I am not sure who's doing the erroneus uprezzing, but it is being done wrong and quite consistantly.
     

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