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  1. Member
    Join Date: Feb 2003
    Location: Washington
    Search Comp PM
    Hello all! I looked through the guides and faqs and forum posts but didn't really see anything that applied to my specific situation.

    I am using FlaskMpeg to convert from VOB to AVI file. That AVI file will then be edited in Adobe Premiere and then I will output back out to AVI. Then I will use TMPGEnc to convert to DVD MPG format to burn a DVD to watch on TV.

    Since this will only be viewed on TV and not designed to be viewed on computer monitor, I should NOT deinterlace, right? So when using FlaskMPEG to rip from VOB, turn off the Deinterlacing option and when writing to AVI format in Premiere, make sure to have Deinterlace turned off there as well, right?

    Thank you!
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  2. Member
    Join Date: May 2001
    Location: United States
    Search Comp PM
    Do you mean, "To Inverse Telecine, or Not to Inverse Telecine"?

    No matter what the viewing platform, it is always better to inverse telecine a video prior to encoding.

    All TV (except for some HDTVs) are displayed as interlaced. This includes PAL TVs.
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  3. Member
    Join Date: Feb 2003
    Location: Washington
    Search Comp PM
    Originally Posted by SLK001
    Do you mean, "To Inverse Telecine, or Not to Inverse Telecine"?

    No matter what the viewing platform, it is always better to inverse telecine a video prior to encoding.
    Would you say that I would inverse this telecine (sounds cool, this phrase!) only during the .VOB to .AVI DVD ripping? But not inverse the telecine when I write out the modified AVI file from Premiere? What would happen if I were to do it twice?

    I would try it out to try and answer my own question, but each ripping takes a good long time to do (the resultant AVI file is 46 gigabytes)

    Thanks!
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  4. Originally Posted by SLK001
    No matter what the viewing platform, it is always better to inverse telecine a video prior to encoding.
    Sorry, but having just read over a dozen threads on this topic, I feel compelled to clarify your statement.

    While you make a point of distinguishing between interlacing and IVTC, you then make an incorrect correlation between the two.

    The interlaced DISPLAY of video on standard (non-digital) TVs has nothing to do with telecined source material. Even computer animation rendered at 29.97fps is going to be interlaced when displayed on screen.

    IVTC removes the fields that were duplicated to brings the footage from 29.97fps back to 23.976fps. What I've been told is that this is unnecessary if your destination format is SVCD or DVD. SVCD and DVDs can be encoded as either progressive frames (at 23.976 fps, to which a 2:3 pulldown is applied), or as fully telecined streams (at 29.97 fps).

    If you DO IVTC, then you need to be sure that the 3:2 Pulldown flag is set on your stream during encoding.
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  5. Member
    Join Date: May 2001
    Location: United States
    Search Comp PM
    While you make a point of distinguishing between interlacing and IVTC, you then make an incorrect correlation between the two.
    Geese... you guys keep beating me up over this. First, there is interlacing, which is how video is sent to the TV screen (odd lines first, then even lines). This type of "interlacing" is not what these guys are talking about - it is INVISIBLE and NECESSARY for your normal TV.

    Then, there is the INTERLACING ARTIFACTS from the TELECINE'ing of the original FILM video. This is the interlacing that everyone is complaining about. So, when the originator asked "To deinterlace or not to deinterlace", it made no sense to me, so I suggested that he meant to inverse telecine. Once IVTC'ed, a 2:3 pulldown would be required.

    Read only a dozen or so posts? Well, read 100-200 more.
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  6. Ha Ha SLK001, still trying? Did you ever get very far with the discussion on how to? It seemed like it got a bit better then it vanished before I saw any great conclusions. I'd still love to find good ways to IVTC then clean up the artifacts. I've read the same 2-300, some give good results, but so far nothing has been quite right. Just living with the 29.976 for now.
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  7. Member
    Join Date: May 2001
    Location: United States
    Search Comp PM
    I personally use Donald Graft's DECOMB filter and frameserve to CCE. It does a pretty good job of IVTCing. If it can't get a proper field match, it will "blend" the two fields to minimize the interlace artifacts - this also works well. I'm sticking with this one.
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  8. Have to look back and make sure? Pretty sure I did. Recall as good results no audio problems (ok, so I always do audio offline with CCE so that's not likely with any CCE combo), reasonable artifact handling and it seemed to deal pretty well with telecine pattern changes. But if I recall corrctly it left things not quite as smooth. Just a bit of a flicker at what I presume was the old 5th frame boundry in motion sequences with clean backgrounds.
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  9. Member
    Join Date: May 2001
    Location: United States
    Search Comp PM
    Earlier versions had that flicker (also, temporal anomalies). Make sure that you used his latest version (don't know the version number).
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  10. Ok, I'll try newer one. I do want to get this figured out. Stopped because I got tired of getting jumped on by folks that felt the need to "correct" the IVTC vs. de-interlace (even when people were reasonably accurate in describing what they were doing!). Wish we could get a sticky thread/ good guide/ ongoing discussion to really work out the best methods or even when and where to use it (YES, I KNOW THE FILM ORIGIN VS. TAPE ORIGIN :P )
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  11. Member
    Join Date: May 2001
    Location: United States
    Search Comp PM
    How about this one. I've been having to convert old films to DVD (pre 1950). I have run across some that were telecined to film for broadcast at 29.97, then IVTC'ed (badly) back to film later, then telecined again. All that is availabe today is the telecined film version. Frame by frame they look very strange, but when viewed at normal speed they look okay.

    As a fallback, I will encode at 29.97 interlaced, if I have to. Viewed normally, it still looks very good.
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  12. Originally Posted by SLK001
    Geese... you guys keep beating me up over this...
    Read only a dozen or so posts? Well, read 100-200 more.
    Oops -- didn't mean to rub salt into any old wounds. Glad to have engaged someone knowledgable in this particular discussion, though.

    Admittedly, I stopped reading old threads when I thought I had reached the point at which every single opinion and approach had been offered, rebutted, disputed, and then re-stated.

    Despite all that, I'm still wondering why you said it "is always better to inverse telecine a video prior to encoding." If I'm going from DVD->DVDR it seems like an extra step that can potentially do more harm than good, no?

    Originally Posted by SLK001
    As a fallback, I will encode at 29.97 interlaced, if I have to. Viewed normally, it still looks very good.
    What is your preferred approach, if 29.97 interlaced is your fallback method? The aforementioned DECOMB/CCE routine?
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  13. Member
    Join Date: Mar 2001
    Location: Antwerp - Belgium (Europe
    Search Comp PM
    Okay, I'll say it one more time (again)...

    If your intension is to view the video onto your TV (and not at your PC) and your source-video IS Interlaced, then leave it interlaced (so not to deinterlace).
    This is similar to the 'flickering', but that's normal. At your TV you'll get a better result when the video already was interlaced, while the TV is interlaced.

    If you're gonna create VCD, then you'll better turn off Interlaced (so 'to deinterlace'), while VCD's standard is restricted to Non-Interlaced.

    Hope you've got enough information with this.
    Author of VCDwizard
    Author of lkVCDimager
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  14. Clean sources with a consistent pattern usually IVTC pretty well. Old sources, with dropped frames or that were never worked over for conversion to digital seem to have problems. The IVTC filters are looking for a certain pattern 3:2 2:3 and it isn't there. If they aren't good about recognizing broken patterns or noise they can create a lot of noise (interlace artifacts, I think bob but I've never seen it) or worse yet even loose information. These can also lead to audio sync issues and as mentioned above flicker in the video.

    My solution is typically just leave the source as 29.976 and do nothing but encode at 29.976 if playing around with things seems to be making it worse. I usually do DVDs and I don't cram them full enough to worry about needing the extra bitrate. The right way though theoretically should always be to IVTC film source material. It seems that a lot of people at least feel they are quite good at it. I just haven't seen any good guides on how to do it and what to do with certain types of problems, mostly just folks who point out that interlaced and telecined aren't the same thing. Doing a good job doesn't usually seem as simple as adding a filter in and setting the pulldown.
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