S3 visual artifacts

Discussion in 'TiVo Series3 HDTV DVRs' started by jaggies, Nov 10, 2006.

  1. jaggies

    jaggies New Member

    3
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    Sep 11, 2003
    Nothern...

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    Has anyone else noticed weird visual artifacts on the S3? These are above and beyond typical "blocking" (macroblocks). Maybe I just have a discriminating eye, but these artifacts are pretty annoying:

    1) Improperly de-interlaced NTSC (SD). Looks like the image has been significantly "de-rez'd". The SciFi channel logo looks more jagged than usual when it happens. It's as if the odd/even fields get mixed up. It's really pronounced when Tivo tries to display content in 480p. I've locked it to always display at 1080i as a result. But I've seen it there too for some content - like Adult Swim (upconverted by Tivo from 480i of course).

    2) Vertical stripes during scenes with lots of camera motion or during scene transition. Looks like typical macroblocks only with a definite vertical stripe pattern. Mostly happens with SD content.

    3) Halos around moving heads. As people move from one side of the screen to the other, sometimes you can see a halo or ghost image traling slightly behind. Single-framing through the video doesn't show the artifact. I mostly see this in HD.

    4) Crawling "schmootz" on scrolling movie credits. When letters move up the screen, sometimes a few rows of pixels from white letters (on black) will stay behind in a somewhat random pattern but eventually turn black. Single-framing through the video does not show this artifact. I've only seen this on HD content.

    I have a Mitsubish DLP 1080p TV and a Comcast PVR as well (Motorola). I dont see any of these artifacts with that combination when I record the same content, so I'm pretty sure it's Tivo.

    I'm wondering if I should try to get it replaced or maybe wait a while until they've had a chance to work out the bugs.

    The unit also appears to have a marginal Tuner, but I'm not as concerned about that right now. It wont reliably tune in ch. 76 (Country Music Channel). It comes and goes as I've seen described elsewhere. But it's not that big of loss, unless they decide to move SciFi to that channel :)
     
  2. bdlucas

    bdlucas Right side up again.

    16,954
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    Feb 15, 2004
    Exurbia
    3 and 4 sound like the kind of artifacts you see when there's corruption of the data stream - for example, rain fade with DirecTV. The two most likely places for this to happen are in transmission and on the disk, but the single-step thing makes both of those explanations seem unlikely. It also seems unlikely to me that a software upgrade would help because the video is processed by dedicated hardware, not software. If it were me I'd try to get it replaced.
     
  3. mman

    mman New Member

    2
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    Feb 13, 2004
    Comcast guy came and brought my cardcards last night. HD looks great :) , the SD channels actually look worse than the Mot 6412 it is replacing, especially when there is movement. It seems to block up and then get clear again when the motion stops.

    I have the S3 1080i locked running directly into my Panasonic 50" plasma via HDMI.

    Does anybody have any ideas on how to fix this?
     
  4. cgould

    cgould Member

    200
    0
    Dec 28, 2002
    Bay Area, CA
    This sounds like macroblocking/MPEG artifacts.
    On liveTV mode, eg "Best" quality? I've never ever seen that...

    The S3 picture quality to me is significantly improved over both the Moto6412 and my old Sony SA1 Tivo (thru SVideo).... even the digital SD channels look much better than the Moto6412 did (and certainly better than the 6412's analog SD upscaling.)

    I would ask if maybe you're trying to record everything at "Basic" quality, except that even that looks pretty good to me (better again than SA1 tivo).

    Is your analog cable quality good? If not, maybe there's lots of noise that's taking up all the mpeg compression bandwidth... then again, at Best (live) quality, you still shouldn't see much.

    What I maybe suspect is you might have ADS, or digital simulcast, and the "analog" stations you are watching are actually digital SD, but w/ really crappy bandwidth.
    Does the picture look the same as other "real" digital-tier SD channels?
    Can you verify w/ your cable company if digital-simulcast is active for your account?
    You can also sometimes go into the Tivo diagnostics and check the channel frequency, see if it says analog tuner or digital... set both tuners to bad analog channels, to to Settings, Diagnostics, if it says QAM for the tuner modulation, you have ADS.

    else, it may be something is messed up in your Tivo tuner, might try to get it replaced.
     
  5. jdk1962

    jdk1962 New Member

    2
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    Oct 29, 2006

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    I am also seeing the vertical stripes. They are most noticeable when watching animated shows such as Spongebob Squarepants. They occur when something moves fast on the screen and seem to affect mostly red and yellow objects. Frame by frame reveals strange ghost images composed of evenly-spaced vertical stripes. I first noticed them occasionally about a year ago, but they have gotten much worse recently. Is this normal for this machine or do I have a bad MPEG encoder board?
     

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