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  1. So, if I understand this right this time, in order to avoid distortion I should...:
    1. either restore the 704x576 original AR of the DVD (end up resizing to 704x576)
    2. or crop (or overcrop) in a specific fashion

    In the end, now that we know 99% that my dvd is ITU 4:3, what is the correct way to resize if I want to play the mp4 file in the exact same video AR shape* as the DVD-video plays, but without the black bars?

    Also take into account, that I assume a hypothetical PAL DVD made from the NTSC DVD in a correct way, exists. That's why I'm talking about 576 height and not 480.



    *by that I mean no distortion on the dimensions of the video objects (e.g. if a moon in the DVD-video is 100% circle, I want it to be 100% circle also in the mp4 video)
    Last edited by provato; 5th Jan 2014 at 09:13.
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  2. Originally Posted by provato View Post
    I want to play the mp4 file in the exact same video AR shape as the DVD-video plays
    At which output? DVD players are schizophrenic -- they follow the ITU spec at the analog outputs, the MPEG 2 spec at the upscaled HDMI output.

    Usually the correct way to handle an ITU capture is to crop 8 pixels of the left, crop 8 pixels off the right (or an unequal amount for a total of 16 pixels) and encode as 4:3 DAR or 10:11 SAR (4:3 NTSC) 12:11 SAR (4:3 PAL). Some people prefer to resize to a 4:3 frame size and encode square pixel.
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  3. Originally Posted by jagabo View Post
    Originally Posted by provato View Post
    I want to play the mp4 file in the exact same video AR shape as the DVD-video plays
    At which output? DVD players are schizophrenic -- they follow the ITU spec at the analog outputs, the MPEG 2 spec at the upscaled HDMI output.

    Usually the correct way to handle an ITU capture is to crop 8 pixels of the left, crop 8 pixels off the right (or an unequal amount for a total of 16 pixels) and encode as 4:3 DAR or 10:11 SAR (4:3 NTSC) 12:11 SAR (4:3 PAL). Some people prefer to resize to a 4:3 frame size and encode square pixel.
    This whole conversation about "correct resizing" started because hello_hello suggested that forcing 12:11 sar was wrong.
    From what you say jagabo, it's a matter of what different people prefer for ITU captures (square pixels, sar 12:11, or even not cropping the black bars at all) I tend to agree with this... and since I want to compare NTSC & PAL mp4 files, I think it doesn't matter which resizing method I choose, as long as I resize NTSC ITU and PAL ITU the same way


    EDIT: I just realised why you "addborders" in your first script jagabo... Because sar 12:11 works with 704x576 if you don't want distortion... So another way to avoid distortion is to resize to 720x576 but with black bars of total 16 pixels on the sides! (right?)
    Last edited by provato; 5th Jan 2014 at 09:49.
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  4. Originally Posted by provato View Post
    since I want to compare NTSC & PAL mp4 files, I think it doesn't matter which resizing method I choose, as long as I resize NTSC ITU and PAL ITU the same way
    Yes. As long as they were both created the same way to start with.

    Originally Posted by provato View Post
    EDIT: I just realised why you "addborders" in your first script jagabo... Because sar 12:11 works with 704x576 if you don't want distortion...
    Yes, assuming the source was ITU to start with -- which looked to be the case (black borders at left and right). The acid test is to find something of known aspect ratio in the picture, like a sphere or wheel viewed directly from the side, and measure it. But you have to be careful, lenses often distort toward the edges and corners.

    Originally Posted by provato View Post
    So another way to avoid distortion is to resize to 720x576 but with black bars of total 16 pixels on the sides! (right?)
    Yes. Again, assuming ITU sampling.
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  5. But I don't know why you're comparing PAL and NTSC this way. Once you start resizing you're changing the video. So you can no longer compare directly.

    For example, try resizing this 720x480 frame to 720x576 using any resizing filter you want. Watch the thin horizontal lines in the "1" area.

    Click image for larger version

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  6. Originally Posted by jagabo View Post
    But I don't know why you're comparing PAL and NTSC this way. Once you start resizing you're changing the video. So you can no longer compare directly.
    You are right to ask because I falsely stated what two videos I want to compare...
    I want to determine if it's better to make a pal mp4 from an NTSC DVD,
    Or to make a pal mp4 from a pal DVD.

    Obviously for so many reasons of different AR and different framerate, I can't really make this comparison.
    So, finally I'm just trying to determine what is the better way to encode a pal mp4, in case ONLY NTSC DVD is available.
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  7. Originally Posted by provato View Post
    This whole conversation about "correct resizing" started because hello_hello suggested that forcing 12:11 sar was wrong.
    I didn't say it was wrong, I was simply pointing out MeGUI will calculate the new DAR/SAR for you so you don't need to work it out.
    What you're wanting to do here.... resize an NTSC video to PAL dimensions while cropping, isn't something you'd typically do when encoding, and if you wanted to crop more (because 8 pixels isn't quite enough to remove all the crud going by your sample), I was simply explaining how to crop away and resize using MeGUI without having to manually calculate the correct DAR/SAR.
    The way I understood it you're not trying to create PAL compliant video as such, just re-encode NTSC to PAL dimensions and the PAR doesn't actually matter as long as the picture isn't distorted.
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  8. Originally Posted by hello_hello View Post
    Originally Posted by provato View Post
    This whole conversation about "correct resizing" started because hello_hello suggested that forcing 12:11 sar was wrong.
    I didn't say it was wrong, I was simply pointing out MeGUI will calculate the new DAR/SAR for you so you don't need to work it out.
    What you're wanting to do here.... resize an NTSC video to PAL dimensions while cropping, isn't something you'd typically do when encoding, and if you wanted to crop more (because 8 pixels isn't quite enough to remove all the crud going by your sample), I was simply explaining how to crop away and resize using MeGUI without having to manually calculate the correct DAR/SAR.
    The way I understood it you're not trying to create PAL compliant video as such, just re-encode NTSC to PAL dimensions and the PAR doesn't actually matter as long as the picture isn't distorted.
    YES! I couldn't put it better than you said it that's what I'm trying but I lack the knowledge of terminology to say it correctly.

    Anyway, I am interested also in megui's automatic sar par dar calculations, so I'll read your posts more carefully to understand it better
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  9. Originally Posted by provato View Post
    So, finally I'm just trying to determine what is the better way to encode a pal mp4, in case ONLY NTSC DVD is available.
    MP4 isn't really NTSC or PAL, it's just a video with a frame size and a frame rate. As you now know, the nature of the source (interlaced, progressive, pulldown), your playback devices (refresh rate, frame size scaling abilities), your preferences (PAL speedup and pitch change for film), and your knowledge/abilities (upscaling, filtering, etc.) determine how the MP4 should be created. There's a lot of variation so you need to handle videos on a case-by-case basis.
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  10. Originally Posted by provato View Post
    You are right to ask because I falsely stated what two videos I want to compare...
    I want to determine if it's better to make a pal mp4 from an NTSC DVD,
    Or to make a pal mp4 from a pal DVD.
    There really is no PAL/NTSC when it comes to MP4, it's just video and pixel aspect ratios. One of the main ideas behind anamorphic encoding is to encode "pixel for pixel". Ideally you'd crop what you don't want and re-encode the remaining video without resizing. The pixel aspect ratio would remain unchanged (unchanged from what you decided the pixel aspect ratio of the original should be).

    I've encoded lots of NTSC DVDs (even though I'm in PAL land) so I don't see the logic in some sort of NTSC to PAL conversion when encoding. If it's an MP4 it'll play using any player capable of playing MP4s. It'll resize to fullscreen correctly without needing to convert it to a PAL resolution and aspect ratio first. What's the advantage of re-encoding an NTSC as a "PAL MP4"?
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  11. Originally Posted by provato View Post
    Anyway, I am interested also in megui's automatic sar par dar calculations, so I'll read your posts more carefully to understand it better
    If you have a look here, MeGUI uses the second list of ITU PARs when ITU is selected for the DVD Input PAR.
    Calculating any new DAR/SAR after cropping and resizing starts there. Resizing to square pixels is also based on those. For non-ITU, MeGUI obviously uses the generic pixel aspect ratios.
    http://forum.doom9.org/showthread.php?p=1058927#post1058927
    Last edited by hello_hello; 5th Jan 2014 at 11:52.
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  12. Hi again guys, and sorry for reviving my thread, but I seem to have found a strange NTSC source that cannot be IVTC'd...

    Here is a sample:
    Code:
    http://www.mediafire.com/watch/xgz7prk0304u7cq/Sample%20Cartoon%20DVD.VOB
    The only pattern I can see:
    3 or 4 out of 5 frames is interlaced OR blended-progressive!

    I'm interested in finding out (if you have the time to help me know):

    -what the #@$% happend and this dvd ended up like that?
    -Is there a pattern between progressive/interlaced frames?
    -Are the fields themselves blended?
    -Is there any way to restore progressive & non-blended frames? (I've tried QTGMC-default settings, but no luck)
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  13. Originally Posted by provato View Post
    but I seem to have found a strange NTSC source that cannot be IVTC'd
    That's because it was never telecined to begin with. It was field-blended to convert from PAL to NTSC. It can't be entirely unblended (not by me anyway), but this should do the job reasonably well:


    Yadif(Order=1,Mode=1)#or QTGMC
    Srestore()
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  14. Well thanks Manono, if you are SURE it's a PAL to NTSC conversion, then I'm going to search and buy the PAL DVD source. (hoping that PAL video will be 2:2 pulldown)

    EDIT: I found my friend's PAL DVD of the same video, and this one has almost every frame blended!
    What's the deal here? They used a PAL tape to make the NTSC DVD, and an NTSC tape to make the PAL DVD?
    Last edited by provato; 19th Jan 2014 at 04:15.
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  15. Originally Posted by provato View Post
    EDIT: I found my friend's PAL DVD of the same video, and this one has almost every frame blended!
    Blended or interlaced? It's quite common for PAL to use 2:2 pulldown but to have the fields split between adjacent video frames. That's easily fixed with TFM() or SeparateFields().Trim(1,0).Weave().
    Last edited by jagabo; 19th Jan 2014 at 06:28.
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  16. Originally Posted by jagabo View Post
    Originally Posted by provato View Post
    EDIT: I found my friend's PAL DVD of the same video, and this one has almost every frame blended!
    Blended or interlaced? It's quite common for PAL to use 2:2 pulldown but to have the fields split between adjacent video frames. That's easily fixed with TFM() or SeparateFields().Trim(1,0).Weave().
    I'll upload a sample tomorrow, because my friend lacks video programs to cut vob/mpeg-2. So he has only sent me an avi file that he cut/encoded in virtualdubmod-mpeg2.

    What is the exact tfm() script somebody needs to use in 2:2 pulldown video?
    Also I doubt that the PAL DVD is 2:2 pulldown, because the episodes have the same duration as the NTSC DVD and not 4% speeded up (or maybe I'm wrong there...?)
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  17. Originally Posted by provato View Post
    What is the exact tfm() script somebody needs to use in 2:2 pulldown video?
    This is usually all you need for "out of phase" progressive PAL:
    Code:
    WhateverSource()
    TFM()
    Originally Posted by provato View Post
    Also I doubt that the PAL DVD is 2:2 pulldown, because the episodes have the same duration as the NTSC DVD and not 4% speeded up (or maybe I'm wrong there...?)
    NTSC film to PAL could be done with 2:2:2:2:2:2:2:2:2:2:2:3 pulldown to keep the original running time. Viewed as interlaced frames you'll see a pattern of 12 progressive frames followed by 13 interlaced frames (or vice versa) repeating.
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  18. It seems more like... 1 interlaced frame followed by 1 progressive frame throughout the sample he sent me. But in some cases all frames seem interlaced. But he made an .avi and an .mp4 sample by encoding (he swears he didn't use any deinterlacer/decomb or similar filter)

    I will post a .vob sample as soon as I get the DVD in my hands
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  19. Originally Posted by provato View Post
    Also I doubt that the PAL DVD is 2:2 pulldown, because the episodes have the same duration as the NTSC DVD and not 4% speeded up (or maybe I'm wrong there...?)
    The NTSC PAL-to-NTSC version has the worst of both worlds. It's field-blended garbage that retains the wrong PAL length. Both versions have PAL speed-up. When I see that kind of thing (which is very very often) I slow both audio and video back to film speed.

    If your PAL source is just phase-shifted, I'd go with that one and still slow it to film speed. There's a chance your NTSC one went NTSC->PAL->NTSC by being field-blended twice (and that I'm wrong about having to slow the speed). And it might explain why your NTSC sample doesn't unblend all that well. I'll be curious to see the PAL sample myself.
    Last edited by manono; 19th Jan 2014 at 14:08.
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  20. Originally Posted by manono View Post
    There's a chance your NTSC one went NTSC->PAL->NTSC by being field-blended twice (and that I'm wrong about having to slow the speed). And it might explain why your NTSC sample doesn't unblend all that well. I'll be curious to see the PAL sample myself.
    I initially suspected NTSC tape -> PAL tape -> NTSC DVD because the NTSC DVD-video has 3 kinds of frames:

    1.Progressive non-blended
    2.Progressive blended
    3.Interlaced (I can see the "lines" in these, whereas in the progressive-blended frames I can see only ghost effect)
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  21. Sorry for being so late, but I just got the PAL DVD yesterday.

    Here is the sample:

    Code:
    http://www.mediafire.com/watch/85h8jj3dxvccy9l/X-men%20PAL%20DVD%20sample.VOB
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  22. More field-blended garbage.

    Yadif(Mode=1)#or QTGMC
    Srestore()
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  23. Hi once again guys!
    I'm in the process of buying different DVDs and studying their interlacing at this time.

    Here is a new one I came across (possibly more field blended garbage):

    Code:
    https://mega.co.nz/#!Jg90lCTB!hi9euHPjB4whmxsLYUuWuNYQimv3S5w4HI-oaug-np4
    I seem to get better results with this script:

    TDeint(mode=2, type=3)
    srestore(25)

    (Keep in mind that I want to keep it 25 fps, OR restore it to 23,976 and then assumeFPS(25) )

    Please take a look at the sample if you have the time, and any advice is greatly appreciated,
    Thank you
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  24. It's the same as before, field-blended NTSC to PAL.
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