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  1. Confirming that the following ffmpeg code will give me 29.97 complete frames per second, with 59.94 fields per second, correct?

    Code:
    ffmpeg -i "C0008.MP4"  -s 1920x1080  -pix_fmt yuv420p  -vcodec mpeg2video  -vb 5.5M  -minrate 5.5M -maxrate 5.5M -bufsize 5.5M  -muxrate 6.0M  -vf  scale=out_color_matrix=bt709:out_range=limited    -flags +ilme+ildct  -top 1  -r 29.97  -color_primaries bt709  -color_trc bt709  -colorspace bt709  -acodec mp2  -ab 192k  -y  -f mpegts output.ts
    MediaInfo reports this:

    Frame rate : 29.970 (30000/1001) FPS
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  2. Member Cornucopia's Avatar
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    No.
    "-top" only sets the field order, it doesn't make it interlaced. It's useless if you started with progressive footage. You'd need either "-vf interlace=..." or "-vf -tinterlace=..." modifiers. Plus must use an encoder that supported interlacing.
    This might be out of date, but here is a link of sample code: https://forum.kde.org/viewtopic.php?f=272&t=129152.
    Haven't tested it myself, so YMMV, UAYOR.

    Scott
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  3. This code makes it interlaced, according to MediaInfo:

    Code:
    -flags +ilme+ildct
    Without those flags MediaInfo reports "progressive".

    https://superuser.com/questions/600030/how-to-convert-1080p-to-1080i-video-using-ffmpeg

    My question about frame/field rate stands.
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  4. With interlaced video the field rate is always twice the frame rate.
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  5. Member Cornucopia's Avatar
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    Don’t base your understanding of compliance of fields/frames on MediaInfo, it is still incomplete as a reporter AND is is not a validation tool.

    Scott
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  6. Originally Posted by Cornucopia View Post
    Don’t base your understanding of compliance of fields/frames on MediaInfo, it is still incomplete as a reporter AND is is not a validation tool.

    Scott
    What do you recommend?
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  7. Member Cornucopia's Avatar
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    Other than hardware tools and/or CRTs? Nothing cheap/free*. Though you can compare with a known true interlaced clip, using your eyes. And also open in AVIsynth, separate fields, and then do field-by-field advance or do overlay/checkerboard/side-by-side, etc comparisons.
    To make your own known-true-intl. clip, you could use HCEnc (which clearly supports interlaced).
    If you have a pro NLE, such as Premiere, you could also open in there and see the difference in how it interprets the footage.
    *If you are going to MPEG2, you could try opening result clip in DGMPGDEC and see what it says about the cadence (percentage of prog vs. int'lace). That at least is free.

    Or if you want to create your own ( ), take a look at this Automatic comparer idea from SMPTE: https://www.smpte.org/sites/default/files/23-1415-TS6-2-IProc02.Pindoria.FINAL_.pdf

    Scott
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  8. Thanks for the suggestions, Scott.

    Since I'm just playin' around, for now I'll take MediaInfo's word that it's interlaced. If there were a remote chance that my footage might air on a 1080i station or network, I could spend the money on a real checker or ask someone who has a real checker to check it, or just submit it and hope it doesn't get rejected.
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  9. Is that original C0008.MP4 interlaced, progressive or you don't know?
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  10. Originally Posted by _Al_ View Post
    Is that original C0008.MP4 interlaced, progressive or you don't know?
    The original is 1080 progressive.
    Last edited by chris319; 24th May 2019 at 06:53.
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  11. Originally Posted by chris319 View Post
    Originally Posted by _Al_ View Post
    Is that original C0008.MP4 interlaced, progressive or you don't know?
    The original is 1080 progressive.
    Then your video is encoded interlaced but contains progressive frames.
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    To make interlaced video from progressive one, you need to use (t)interlace filter.
    Also you can split fields and/or compare them with ffmpeg too.
    You can even use mpv player with -vf/-af/-lavfi-complex command incarnation.
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  13. How about this?

    Code:
      ffmpeg -y -i "C0008.MP4"  -flags +ildct+ilme  -vf tinterlace=7  -s 1920x1080   -vcodec mpeg2video     output.mpg
    MediaInfo reports "interleaved fields"

    Without those two flags MediaInfo reports "progressive"
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  14. First example
    Yes, provided command line will give interlace encoded mpeg-2 video - it can be progressive or interlace - assumption is that your source is 30000/1001 frame rate, if your source is 60000/1001 then you need apply interlace filter (filter to perform conversion - frames to fields) (second example). I see error - there is only valid tinterlace=4 (TFF) or tinterlace=5 (BFF) - other types of tinterlace are invalid.
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  15. MediaInfo reports Interlaced and TFF.
    Last edited by chris319; 24th May 2019 at 15:07.
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  16. Originally Posted by chris319 View Post
    MediaInfo reports Interlaced and TFF.
    Not my circus and not my monkeys...
    https://ffmpeg.org/ffmpeg-filters.html#tinterlace

    ‘mergex2, 7’

    Move odd frames into the upper field, even into the lower field, generating a double height frame at same frame rate.
    Code:
     ------> time
    Input:
    Frame 1         Frame 2         Frame 3         Frame 4
    
    11111           22222           33333           44444
    11111           22222           33333           44444
    11111           22222           33333           44444
    11111           22222           33333           44444
    
    Output:
    11111           33333           33333           55555
    22222           22222           44444           44444
    11111           33333           33333           55555
    22222           22222           44444           44444
    11111           33333           33333           55555
    22222           22222           44444           44444
    11111           33333           33333           55555
    22222           22222           44444           44444
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  17. Why are you bringing up ‘mergex2, 7’ if it's not valid?
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  18. Originally Posted by chris319 View Post
    Why are you bringing up ‘mergex2, 7’ if it's not valid?
    Well... this is YOUR idea not mine

    Originally Posted by chris319 View Post
    How about this?

    Code:
      ffmpeg -y -i "C0008.MP4"  -flags +ildct+ilme  -vf tinterlace=7  -s 1920x1080   -vcodec mpeg2video     output.mpg
    MediaInfo reports "interleaved fields"

    Without those two flags MediaInfo reports "progressive"
    Seem you don't see difference between progressive coded as interlace and converting progressive to interlace - IMHO you should rethink what is your gaol, what is your source...
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  19. You're beating a dead horse, Pandy.

    I no longer use ‘mergex2, 7’ or the code from the old post you quoted. They are no longer germane to the discussion.

    Thanks for the tip on tinterlace 4, though.
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  20. Originally Posted by chris319 View Post
    You're beating a dead horse, Pandy.

    I no longer use ‘mergex2, 7’ or the code from the old post you quoted. They are no longer germane to the discussion.

    Thanks for the tip on tinterlace 4, though.
    lol
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