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  1. Member
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    If not, is there any filter that can help reduce this?
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  2. Member edDV's Avatar
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    maybe, maybe not

    post a sample
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    See attached. I think a previous post I did a while ago (with another sample, if you can have a look), is probably related to the same issue (although on this sample it can be seen more clear)?

    https://forum.videohelp.com/threads/336555-Cleaning-Up-Weird-jittering-in-the-backgroun...15#post2091615

    Thanks!
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  4. Member edDV's Avatar
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    Difficult to tell from that sample but looking at the horizontal "H", the line scan looks OK. TBC isn't the main problem.

    Looks more like RF or subcarrier decode by products.

    What is the source format?
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    Source is VHS connected to an ATI Theater 550 using a SVHS connector.
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  6. Banned
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    Originally Posted by cfelicio View Post
    Source is VHS connected to an ATI Theater 550 using a SVHS connector.
    I think you mean "s-video connector", not "SVHS connector". SVHS is a tape format, not a connector or wire. SVHS can be played with any kind of cable that your player supports, it doesn't necessarily require an s-video cable.

    All that aside, did other viewers notice that the noise doesn't become obvious until the title characters start to fade, then it builds in rapid cycles. The noise wouldn't be cleared by a TBC (although a line level TBC would give a slightly cleaner signal by fixing some of the flicker and underlying roll), because the noise is not caused by the kind of playback timing/sync issues that TBC's are designed to address.

    I applied a couple of strong spatio-temporal and chroma filters that cleared about 75% of the noise. But it took two passes and there wouldn't be much left of the original image. IMHO the noise is from physical damage to the tape's magnetic oxide layer, or to circuit problems somewhere in the capture setup. Is the noise present when playing thru other devices? I've seen tape damaged this way by exposure to strong magnetic fields, such as from tv degaussing coils or storing tapes next to big subwoofer enclosures, or from the use of cheap tape rewinders.

    Recording directly to high-compression formats like MP4 makes noise much more difficult, if not impossible, to remove.
    Last edited by sanlyn; 20th Mar 2014 at 17:20.
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  7. Member edDV's Avatar
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    Originally Posted by cfelicio View Post
    Source is VHS connected to an ATI Theater 550 using a SVHS connector.
    Do you see similar noise in e to e mode with a known good input?

    Do you see similar noise when playing other tapes?

    Idea is to separate tape issues from player-capture issues.
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  8. Banned
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    The ATI 650 has a comb filter that often fixes this problem. Note in the video that the herringbone pattern is most evident in areas of pure color with no detail. I've seen discussions about chroma and luminance channels not behaving correctly (many people give many reasons for this). I don't know if your ATI 550 has the 650's comb filter.

    In any case, it doesn't help to record bad tape to MP4, MPEG, etc. Capture damaged tape to uncompressed AVI or use lossless huffyuv.
    Last edited by sanlyn; 20th Mar 2014 at 17:20.
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  9. Video Restorer lordsmurf's Avatar
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    That's chroma noise embedded in the signal, possibly from a re-used tape or a cheap tape, or a crappy VCR making the recording.

    TBC fix this? No.
    Comb filters fix this? No.
    Software NR? Possibly clean it up some.
    Fully remove it? Doubtful.
    Want my help? Ask here! (not via PM!)
    FAQs: Best Blank DiscsBest TBCsBest VCRs for captureRestore VHS
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    LS, I played around a bit and removed most of it. Downside: not much video left. It's mostly damage.
    Last edited by sanlyn; 20th Mar 2014 at 17:21.
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    Thanks all for your feedback, this source was captured in MPEG2 originally and a JVC VCR HR S3500U was used. I looked at other tapes captured using the same setup, and didn't notice this type of issue (apparently only happened on this one), so it looks like the tape is damaged and a TBC wouldn't help in this case
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  12. Banned
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    Come to think of it, my old JVC made simliar noise when it hit a stretch of bad tape it couldn't play. Changing players didn't help. Shucks.
    Last edited by sanlyn; 20th Mar 2014 at 17:21.
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