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  1. I want to export an edit of progressive footage in Premiere, but with interlacing on the final output file.

    My project sources are two HD videos, both progressive. One is 25fps, the other 30fps.
    I've overlayed one on top of the other (the top one set to 50% opacity) in Premiere, and used a Project setting of DV PAL SD 25fps.

    When I export, although Media Info reports the outputted DV file as being interlaced, I can see visually that it hasn't been, there's no combing in any movement.
    And when I put it onto DVD and watch through a SD CRT TV (the final goal in this project) the picture's very flickery, again suggesting it's not interlaced.

    Is there a way to solve this in Premiere, or a way to treat the file with something like ffmpeg?
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  2. Originally Posted by Gibson's Squares View Post
    I want to export an edit of progressive footage in Premiere, but with interlacing on the final output file.

    My project sources are two HD videos, both progressive. One is 25fps, the other 30fps.
    I've overlayed one on top of the other (the top one set to 50% opacity) in Premiere, and used a Project setting of DV PAL SD 25fps.

    When I export, although Media Info reports the outputted DV file as being interlaced, I can see visually that it hasn't been, there's no combing in any movement.
    And when I put it onto DVD and watch through a SD CRT TV (the final goal in this project) the picture's very flickery, again suggesting it's not interlaced.

    Is there a way to solve this in Premiere, or a way to treat the file with something like ffmpeg?


    You would need 50p footage to make true interlaced content. Just encoding it as interlaced would be 25p encoded as interlaced. It's still 25p. You can try to interpolate the 25p footage with "in between" frames to generate fake 50p , but it often has issues with artifacts

    What was the reason for the 50% overlay ?

    Can you clarify what you mean by "flickery" ? Do you mean more of a motion problem, such as not smooth footage? or luminance "flicker" such as changing brightness? Or buzzing lines / aliasing ?

    When making a DVD, the output should be MPEG2, not DV ...
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  3. Ah, shoot, I didn't think of using 50p when selecting the recording format in the camera. I'll know for next time.
    How would I interpolate the footage to a faux 50p? (avisynth isn't really an option, I'm on mac)
    Out of interest how do broadcasters do it when they use phone footage, etc..?

    The 50% overlay is merely the effect I want to create for the final piece (two bits of ambient footage overlaying each other).

    By flickery I mean a motion problem. It's like the frames are jumping back and fourth once or twice per second. It's only noticeable through the CRT TV. The effect appears worse in the piece of footage with more motion. The picture is otherwise clear. At first I thought it was the field order being incorrect of the output file - I can't remember what effect that would produce though?

    Yes, I know DVD needs MPEG2, but for some reason my Preiere doesn't have that output option. It's easier for me to convert DV with ffmpeg than trawl the internet for missing codec issues which will inevitably just lead to the solution of 'reinstall Premiere'(!).
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  4. Originally Posted by Gibson's Squares View Post
    How would I interpolate the footage to a faux 50p? (avisynth isn't really an option, I'm on mac)

    Newer versions of premiere can interpolate footage using optical flow . Or using Timewarp effect, or 3rd party plugins like twixtor

    FFMpeg can do motion interpolation too, using minterpolate
    https://ffmpeg.org/ffmpeg-filters.html#minterpolate

    Or Vapoursynth on a Mac (has many avisynth functions or equivalents)



    Out of interest how do broadcasters do it when they use phone footage, etc..?

    Typically, phone footage isn't used... And modern phones can shoot 120+ FPS . If low fps phone footage is used, it's only for brief segments. Generally motion interpolation is not used in broadcast because of artifacts. High quality interpolation typically requires user input / masking/ tracking/time/money - so it's typically not used, especially when a big budget could have afforded a high speed camera in the first place. Although some of the newer AI research methods look promising


    By flickery I mean a motion problem. It's like the frames are jumping back and fourth once or twice per second. It's only noticeable through the CRT TV. The effect appears worse in the piece of footage with more motion. The picture is otherwise clear. At first I thought it was the field order being incorrect of the output file - I can't remember what effect that would produce though?

    Yes - Jumping back and forth suggests wrong field order; but field order shouldn't matter with progressive content.

    Or it might some other issue with the workflow , ffmpeg . Hard to say without input/output file examination or more details


    Yes, I know DVD needs MPEG2, but for some reason my Preiere doesn't have that output option. It's easier for me to convert DV with ffmpeg than trawl the internet for missing codec issues which will inevitably just lead to the solution of 'reinstall Premiere'(!).
    PAL DV might be OK (I'm assuming that's what you're making), but you wouldn't want to use NTSC DV intermediate because of the 4:1:1 chroma
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  5. Yes, I know DVD needs MPEG2, but for some reason my Preiere doesn't have that output option. It's easier for me to convert DV with ffmpeg than trawl the internet for missing codec issues which will inevitably just lead to the solution of 'reinstall Premiere'(!).
    Then it would be better to export as a lossless intermediate, like Lagarith / MagicYUV / UT Video ; DV adds one generation loss.

    Out of interest how do broadcasters do it when they use phone footage, etc..?
    Apart from the fact that broadcasters can do silly things (like displaying 4:3 footage awfully stretched to 16:9, or awfully cropped to 16:9), I don't think that they do anything fancy like advanced frame interpolation (at least for TV news reports, which are meant to be broadcast once, perhaps the footage is sometimes treated more carefully for documentaries, but I've seen ugly things in documentaries too), so it must be generally limited to simple frame duplication or frame decimation.

    By flickery I mean a motion problem. It's like the frames are jumping back and fourth once or twice per second. It's only noticeable through the CRT TV. The effect appears worse in the piece of footage with more motion. The picture is otherwise clear. At first I thought it was the field order being incorrect of the output file - I can't remember what effect that would produce though?
    It may produce that kind of effect on a fast panning if one frame out of 5 is duplicated. It probably doesn't actually “jump back”, but your brain, your “computer brain” as Jean-Claude Van Damme used to say, expects a forward motion, so it gets confused when there's none. If it's the other way around (30=>25FPS) it should be the opposite, so I'm not sure, and my “computer brain” is hungry right now.
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  6. I've gone back and studied the output file (DV) more closely, frame by frame. The weirdest thing is happening. Remember I have Footage A (filmed at 30fps) overlayed on Footage B (filmed at 25fps).

    Footage A *is* interlaced on some frames, but not all. Eg often for 3 frames out of 5, but it fluctuates slightly. This on/off of the interlacing would explain why that footage looks so flickery on the CRT.

    Footage B isn't interlaced at all, but it doesn't look so flickery on the CRT TV, though possibly because there's very little movement to it.

    Am I right in thinking that because Footage A has more than 25 frames, Premiere is using the 5 extra frames to interlace when it can, hence the interlacing coming and going?
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  7. Originally Posted by Gibson's Squares View Post
    I've gone back and studied the output file (DV) more closely, frame by frame. The weirdest thing is happening. Remember I have Footage A (filmed at 30fps) overlayed on Footage B (filmed at 25fps).

    Footage A *is* interlaced on some frames, but not all. Eg often for 3 frames out of 5, but it fluctuates slightly. This on/off of the interlacing would explain why that footage looks so flickery on the CRT.

    Footage B isn't interlaced at all, but it doesn't look so flickery on the CRT TV, though possibly because there's very little movement to it.

    Am I right in thinking that because Footage A has more than 25 frames, Premiere is using the 5 extra frames to interlace when it can, hence the interlacing coming and going?

    Yes , that explanation fits. It's actually "50" samples per second (50 fields per second) with the interlaced PAL DV sequence setting . So the 25p footage is evenly divisible as a whole number, thus no combing. The 30 doesn't divide nicely into 50 so you get occasional combing. Also the movement isn't smooth because not evenly divisible issue. How it plays back depends on the hardware and display setup . Some perform adaptive deinterlacing, it might look slightly better
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  8. Hmmmm... I minterpolated both pieces of progressive footage to 50fps, put them into my project, exported as PAL DV 25fps interlaced, but I'm still getting the flickering on CRT from the footage that was originally 30fps.

    I've gone through the exported video frame by frame and both pieces of footage are now definitely interlaced on every frame, unlike before. But the flickering is still the same.

    I noticed the flickering is especially worse in lighter/white areas. Could it be the colours are too bright/not broadcast safe for a CRT? I tried putting an adjustment layer on the whole thing and dialling the white down to 235, but the flickering remained.

    Is there anything else that could be causing me this problem? When I slow the footage down in my DVD player there's no flickering at all, only when playing at 25fps.

    Here's the specs from Media Info of the troublesome file that's causing the flicker, in case there's any obvious cause within it:

    ------------------------------------------------------------
    General
    Complete name : P1150508.MOV
    Format : MPEG-4
    Format profile : QuickTime
    Codec ID : qt 2007.09.04 (qt /pana)
    File size : 634 MiB
    Duration : 5mn 4s
    Overall bit rate mode : Variable
    Overall bit rate : 17.5 Mbps
    Encoded date : UTC 2019-09-26 22:47:05
    Tagged date : UTC 2019-09-26 22:47:05
    Writing library : pana
    IsTruncated : Yes

    Video
    ID : 1
    Format : JPEG
    Codec ID : jpeg
    Duration : 5mn 4s
    Bit rate mode : Variable
    Bit rate : 16.9 Mbps
    Width : 1 280 pixels
    Height : 720 pixels
    Display aspect ratio : 16:9
    Frame rate mode : Constant
    Frame rate : 30.000 fps
    Color space : YUV
    Chroma subsampling : 4:2:0
    Bit depth : 8 bits
    Compression mode : Lossy
    Bits/(Pixel*Frame) : 0.612
    Stream size : 615 MiB (97%)
    Language : English
    Encoded date : UTC 2019-09-26 22:47:05
    Tagged date : UTC 2019-09-26 22:47:05

    Audio
    ID : 2
    Format : PCM
    Format settings, Endianness : Big
    Format settings, Sign : Signed
    Codec ID : twos
    Duration : 5mn 4s
    Bit rate mode : Constant
    Bit rate : 512 Kbps
    Channel(s) : 2 channels
    Channel positions : Front: L R
    Sampling rate : 16.0 KHz
    Bit depth : 16 bits
    Stream size : 18.6 MiB (3%)
    Language : English
    Encoded date : UTC 2019-09-26 22:47:05
    Tagged date : UTC 2019-09-26 22:47:05
    ------------------------------------------------------------
    Last edited by Gibson's Squares; 30th Sep 2019 at 17:02.
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  9. Originally Posted by Gibson's Squares View Post
    Hmmmm... I minterpolated both pieces of progressive footage to 50fps, put them into my project, exported as PAL DV 25fps interlaced, but I'm still getting the flickering on CRT from the footage that was originally 30fps.

    I've gone through the exported video frame by frame and both pieces of footage are now definitely interlaced on every frame, unlike before. But the flickering is still the same.

    I noticed the flickering is especially worse in lighter/white areas. Could it be the colours are too bright/not broadcast safe for a CRT? I tried putting an adjustment layer on the whole thing and dialling the white down to 235, but the flickering remained.

    Is there anything else that could be causing me this problem? When I slow the footage down in my DVD player there's no flickering at all, only when playing at 25fps.

    Here's the specs from Media Info of the troublesome file that's causing the flicker, in case there's any obvious cause within it:
    Not sure, need a better description of the "flicker." - it's a term that can mean a dozen different things

    Are there sharp "lines" in the footage ? Too sharp, especially thin horizontal lines, can cause flicker with interlace . Often UHD or HD down to SD DVD can cause flicker if the downscaling is too sharp . You might have to low pass or do a slight blur . But need more info before you can say this is the case for you

    Can you upload a sample cut from the DVD ? Stream copy a mpeg2 segment that has flicker
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  10. Have made a short test clip on the same camera, and it displays the same flicker problem when seen on a CRT.

    Here's my test file as shot on my 30fps camera, and a 25fps VOB of it which flickers when viewed on a CRT: https://we.tl/t-x7IGkV06dF

    I used ffmpeg minterpolate to make the 30fps file 50fps, then used Premiere to make it PAL SD 25fps.

    My actual project I'm having problems with is similar to this footage. No sharp lines, and I did actually blur my footage by a few pixels anyway, which didn't solve the flicker.

    The best way I can describe the flicker is it looks like every 2 or 3 frames it's jumping back a frame. I was fully expecting when I slowed it to frame-by-frame to see this happening, but it doesn't. there's no flickering in slow motion. Visually the flickering looks a bit like the effect in this music video, at 0:45, 0:50 and 0:56 only not paused like that, my footage does keep moving.

    I've tried two different CRT TVs, and tried playing the DVD from two different DVD players, and always get the same flickering.

    Anyone able to work out what's going wrong?
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  11. The DVD sample is encoded TFF (top field first) . But the content is BFF (bottom field first)
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  12. Thanks poisondeathray.

    Is the original camera footage not progressive - does progressive have fields?

    When I first ran into this problem I did try ticking the box in Premiere to swap the field order of the troublesome footage, but it made no difference.

    How is it best to solve this? I assume I need to swap the field order on one or other of the files?
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  13. Progressive doesn't really have a valid field order

    When you have 50p footage , the way you (re)-interlace it to make 25i determines the field order

    With 50p assets, normally you would use a 50p timeline to edit. From that timeline you can export multiple formats (including 50p for say, youtube)

    By convention , "DV" - the format - is BFF . So the DV sequence setting is typically BFF. I can't recall off hand if you can switch the field order in the export settings (and it sounds like you're using an older PP version), but check that - If you used a DV timeline sequence setting, and export BFF in the encoding settings it should all match up
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  14. The way I would set it up in older version of PP

    In the sequence settings, I would set it to "desktop" . That "unlocks" all the other settings so you can enter whatever you want.

    Usually you would set it to the least damaging / highest resolution and framerate format of your main assets . So if you had 1280x720p50 (fake, interpolated, but still it's the "highest"), that's what I would set it to 1280x720, progressive, 50p. That same project can double up for other export formats such as BD, youtube etc... So you only have to do 1 edit. But if you already set the sequence to 720x576PAL DV, you've already "pigeon-holed" yourself into a lower resolution, interlaced, compromised format . e.g. It would be downscaled and upscaled if you were exporting for HD and much worse

    So for the DVD, just export it using the PAL interlaced DVD setting from that 1280x720p50 sequence and everything should work fine. NLE's typically don't have problems with progressive downscaling
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  15. You're using ffmpeg to do the actual mpeg2 encoding from the DV export from PP - is that correct? Or what are you using ? Just set whatever you are using for the actual DVD/MPEG2 encoding to BFF instead of TFF
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  16. I'm using Toast to make the DVD from the DV file, and when I just checked the conversion settings the field order was set to 'Automatic', which you'd think would leave the field order as it was in the DV file, but no, it was always switching it from BFF to TFF.

    I have now switched off 'Automatic' and set it to BFF, and that test clip and my original edited project now play perfectly.

    Thanks so much for your patience and expertise on this, Poisondeathray.
    I've learnt so much over the past few days that will be useful on similar future projects.
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  17. Cheers

    Of course, "BFF" means something entirely different to people of this generation . I can't believe it's officially in some English dictionaries

    https://www.lexico.com/en/definition/bff
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