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  1. Hi,
    First post, so go easy, but i desperate so decided to join and post a question.
    I have a rendering problem that been bugging me for a long time.
    I have a one set of footage on from a small mobile camera (chinese mini cam mobius) which only records at 30FPS.
    I have another set that is recorded at 25FPS PAL on a Sony a5000. I am in a pal region.
    When i merge both sets of footgage in vegas pro and render them in either 25 or 30fps i get ghosting on one that is not native frame rate.
    This ghosting is generally much worse on a moving subject and it seems to show an interlaced frame ie a chost image of the moving object.
    Is there anything i can go to fix this? Is my only solution to ditch the 25FPS sec camera and get one that has 30 FPS at great expense!
    Cheers and thanks in advance!
    Im on PC i5, vegas pro 12.
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  2. Disable smart resampling. Right click on an event or clip => properties => disable smart resampling . This means vegas will add duplicate frames or drop frames to make up the frame rate to the project settings frame rate and export frame rate. So motion won't be very smooth, it will be jerky with a 25 fps / 30fps mix

    If one or more of your assets are interlaced, change the project properties to deinterlace=> interpolate instead of "blend"

    If you are in the UK, and/or if most of your footage is 25 fps , I would use that base frame rate

    Another potential problem is "variable frame rate" with the mobile camera. It might not be 30.0 FPS, rather speeds up/slows down in sections. This can cause potential problems with sync issues when editing with a NLE . You can check with mediainfo (view=>text)
    https://www.videohelp.com/software/MediaInfo
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  3. Thanks for the reply. Will Give it a try.
    One question
    If the two footages are 25FPS and 30FPS, would you rather drop frames from the 30FPS and bring it down to the 25FPS or take the 25FPS UP in the render.
    The 25FPS is better quatlity footage, 14MBS i think the other is 30FPS is i think 720 at 8MBS.
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  4. Thanks for the media help link, heeres the info.
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  5. Originally Posted by guitarman320 View Post
    If the two footages are 25FPS and 30FPS, would you rather drop frames from the 30FPS and bring it down to the 25FPS or take the 25FPS UP in the render.
    Whichever way you do it it won't look pretty. As PDR has already mentioned in post#2, the motion will be 'jerky' - either because of missing - or duplicate - frames.

    You would probably get better results using a technique called 'optical flow' - although even that is not always perfect (depends on the content)

    The 2 clips listed below show an iphone promotional clip, originally recorded at 30fps. The second clip is the same thing converted to 25fps using free optical flow software. (Each clip is about 25MB)...

    http://www.jp137.com/lvs/iphone30.mp4

    http://www.jp137.com/lvs/iphone25.mp4

    .....but there is a catch (naturally!) The software used was a plugin for Avisynth called MVtools2. If you're not familiar with Avisynth, there is a bit of a 'learning curve' to it.

    It's not actually difficult to do (a text copy of the actual script used is attached).

    There is a Vegas plug-in that can give you similar results - Twixtor - but it's not cheap!

    Taking the same technique one stage further can produce even more impressive results. Here's the same clip at 50 fps :

    http://www.jp137.com/lvs/iphone50.mp4

    ... even smoother!
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    Last edited by pippas; 4th Jan 2017 at 15:23.
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  6. Member
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    The 50 fps version is impressive. Same script? Any way to fix the fade-to-black? Or was that a compression artifact?
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  7. Pretty much the same script (see attached)..... I don't recall now whether the original 30fps 'promo' clip had fades, or whether I added them? The 25 and 50fps clips are simply frame rate conversions of that 30fps clip - complete with original fades.

    It's only quick and dirty sample to try and show that optical flow can improve on frame duplication (or cutting) ..... I'm sure that with further tweaks it might be improved.... MVtools has a lot of 'tweakable' parameters ..
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