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  1. Member
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    Hello,
    I dont post here very often, I'm the type of person who likes to find my own answers. Anyways, as the topic suggests, I have a few questions about converting a PAL video to NTSC and authoring it to dvd. I've had a number of problems, and the quality of the video has suffered as a result. From my understanding, there are 2 kinds of NTSC, NTSC Film (29.97 fps) and NTSC TV (23.97 fps). My attempts at converting a video to NTSC-film look terrible, it has an odd choppiness to it that's difficult to explain without seeing it, and im sure its becuase of the extra 5 frames required every second. So I have a multi-part question for anybody who might know.

    1. Can you author DVD's at NTSC-tv fps?
    2. Would it then be possible to play a PAL video at an NTSC-tv frame rate, instead of dropping frames?
    (i ask this becuase it would only mean a 4% (~1 fps) increase in time. and im sure it would go unnoticed.)
    3. If the above is possible, how do i go about stretching my audio, so it stays in sync?
    4. What then about pitch?
    (the video and audio may be in sync, but the sound may have a lower pitch.)

    If you can answer even one of the questions above, you'd really be helping me out.
    Thanks.
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  2. Man of Steel freebird73717's Avatar
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    What is your source video? Is it avi or other?

    You could convert your video to ntsc resolution i.e. 352x240, 352x480, or 720x480 but use the pal 25 fps frame rate. Then put your newly encoded elementary video stream through dgpulldown and use the 25 -> 29.97 option. Then you can use your untouched audio and your new m2v with irregular pulldown added. And yes dgpulldown does work in linux just fine via wine.
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  3. Member
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    Would that not have the same effect as converting to ntsc-film?
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  4. Get Slack disturbed1's Avatar
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    Originally Posted by ronkkrop
    Would that not have the same effect as converting to ntsc-film?
    Read what is telecine and pulldown from the glossary. If you want more information than that read these -
    http://www.dvdfile.com/news/special_report/production_a_z/3_2_pulldown.htm
    http://en.wikipedia.org/wiki/Telecine

    NTSC-Film is 23.976 fps. Called film, as most movies are shot on film at a rate of 24fps, then pulldown is applied to add RFF to the video streams to make it appear as NTSC-Video at 29.970 fps. Your DVD player understands RFF and will decode the film at the native 23.976 fps.

    Doing as freebird73717 suggested, keeps the film at the same frame rate (no audio sync issues), and DGPulldown will then add the needed RFF to make the video appear as NTSC-Video at 29.970. Just as with NTSC-Film which has pulldown applied, the DVD player will see these RFF and decode properly.

    Short answer -

    Encode at 720x480 at 25fps, run the .m2v through dgpulldown select 25->29.970 and author.

    ffmpeg can encode a pal source to ntsc and keep the audio in sync.

    ffmpeg -i file.foo -target ntsc-dvd out.mpg

    ffmpeg has other options such as aspect ratio, resize, crop/pad, min/max/avg bitrate, and so on.
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    Thank you for the much needed info guys.

    Distubed1, i was using ffmpeg, to convert these videos to NTSC and thats where i ran into problems. Granted ffmpeg is probably the best resource for us linux users out there, but when going from 25fps to 29.97fps using the -target ntsc-dvd option made my video look choppy. ill give the dgpulldown a shot and see what happens.
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  6. Get Slack disturbed1's Avatar
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    Use the bitrate options. If you're target bitrate is 5500kb/s -

    -minrate 5500k -maxrate 5500k -b 5500k

    Kind of stupid you'd need all 3 but it works.

    You will get higher quality, and much more simplicity using HCEnc via Avisynth and dgpulldown, or just use freebird73717's HCBatch <plug :P: >. The only other option is to play the file with mplayer, add filters, and pipe into ffmpeg to encode, since ffmpeg doesn't have any built in noise/sharpening filters. It does have -nr (noise reduction) but I've notice no speed hit nor image difference no matter if I put -nr 2.0 or -nr 250.
    Linux _is_ user-friendly. It is not ignorant-friendly and idiot-friendly.
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  7. Member
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    yeah mostly i was using -sameq ... ill give those bitrate options a try anyways.

    BTW dgpulldown seems to be working quite well, no real visible difference between the pal and newly converted ntsc video... I'm just having a hard time understading the math that makes it work.
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  8. Get Slack disturbed1's Avatar
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    It's like magic
    Linux _is_ user-friendly. It is not ignorant-friendly and idiot-friendly.
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  9. Member
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    ha ha...no doubt...

    hey...when im done with dgpulldown, is it possible to multiplex them with ffmpeg? becuase i tried this earlier to no avail.

    ffmpeg -i foo.m2v -i bar.ac3 foobar.mpg

    ...and come to think of it, that probably won't produce a mpeg2 video. and from previous tests, i know that -vcodec mpeg2video doesn't work.

    I do have mplex on my system, but i haven't gotten around to reading up on how to do it... the man page is loooooooong.
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  10. Member edDV's Avatar
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    Why do you need to convert it?

    Everyone can watch it on a computer monitor. Many analog component HDTV's play component PAL from a PAL capable Chinese DVD player. (rarely from composite or S-Video).
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  11. Get Slack disturbed1's Avatar
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    mplex -f 8 -o out.mpg file.m2v file.ac3

    ffmpeg -i file.m2v -i file.ac3 -vcodec copy -acodec copy out.mpg

    The mplex output can be directly used with dvdauthor. If you're using something like DVDStyler, leave them as elementary streams.

    short dvdauthor
    dvdauthor -o /vobfiles/dir -t file.mpg

    or

    dvdauthor -o /VOBFiles/dir -t -i 'post=jump title 1;' file.mpg
    Linux _is_ user-friendly. It is not ignorant-friendly and idiot-friendly.
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  12. Banned
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    Do note that the choppiness could possibly be a field encoding issue and ffmpeg is not using the correct field by default in the encode. Since I don't ever use ffmpeg I can offer no advice on how to fix this issue, I simply point out that it could be part of the problem. Stated another way, ffmpeg may be encoding as top field first when it needs to be bottom field first or vice-versa.
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  13. Member
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    intresting jman98, ill look into that.

    what does topfield and bottomfield mean?
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