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  1. Member
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    I am using DESHAKER to stabilize the image in a video taken from a 16mm film. The image moves up and down very slightly. When I use DESHAKER it reduces the movement, but does not remove it completely. In the instructions it says you can alter the numbers in Motion Smoothness to achieve any degree of stabilization you want, but I've tried numbers -1, 4, 40 and 400 and it seems to make no difference. What am I missing?
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  2. Perhaps your max correction limits are set too low ?

    Perhaps the pass 1 analysis settings weren't accurate enough ? Try using every pixel, full scale, smaller block sizes
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  3. Deshaker doesn't work well when parts of the frame are moving up and other parts down (or left/right) due to rolling shutter distortions. You'll probably have to provide a sample for more detailed assistance.
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    poisondeathray I'll try that
    jagabo there's no rolling shutter distortion because this is taken from 16mm film. The problem shows up on a totally static scene. How do I provide a sample?
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  5. Originally Posted by timsky View Post
    there's no rolling shutter distortion because this is taken from 16mm film. The problem shows up on a totally static scene.
    Many film scanners now use CMOS sensors and can get rolling shutter distortions from film bounce.

    Originally Posted by timsky View Post
    How do I provide a sample?
    What's the source? DVD (VOB or MPG)? Use a tool like Mpg2Cut2 to extract a short clip that shows the problem and upload it to this site. Other containers will require some other program.
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    poisondeathray: I tried full scale, use all pixels, blocks that have match value <30, motion smoothness horiz 4, vert 4 and it's still the same
    jagabo: this was scanned by a laser. Sample uploaded (unstabilized)
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  7. When I reduced the frame size to 1280x720 DeShaker worked pretty well. I think all the grain is confusing DeShaker at full res. You might try running a noise filter before the first pass of DeShaker, then turning it off for the second pass.
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    I sharpened up the film before trying to stabilize it. The sharpening improved the resolution enormously, but increased the grain. If I try Deshaker on it before sharpening it, then sharpen it later, will that be better? If not how would I find and use a noise-filter?
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  9. I tried applying the Blur (crude de-noising) and Sharpen (at 20, makes some of the remaining noise worse but sharpens edges a bit) filters while running the first pass, then disabling them during the second pass. That worked pretty well for stabilization. I cranked DeShaker's smoothness settings up to 90000.

    Other denoise filters didn't work as well for stabilization because they tend to leave the worst of the noise in the picture -- because they assume small local variations are noise but large local variations are picture detail. When the noise is very heavy they assume it's picture detail.
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  10. Deshaker is more suitable for smoothing out handheld pans, not rock stable tracks - typically a different kind of motion tracker and stabilizer is used for those purposes .

    I don't know what other tricks or settings you could adjust to "convince" deshaker to work here . The author posts at doom9, you could ask there

    Is your whole film framed in the same manner (shot stationary) , or are there other scenes ?

    Typically degraining is usually done before other manipulations (clean up, dirt/ spot removal) , then sharpenining, then regraining is usually last
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  11. It looks like a strip composite was attempted at the end - it doesn't match the motion and you see the upper and lower portions of the frame "break apart" from the middle . The grain also stops "moving" in those overlay setions. Was that something you attempted or did the lab send it to you like that ?

    (That's a big reason why degraining is usually done first - you can do motion tracked repairs to "borrow" data from adjacent frame to fill over big defects such as scratches , dirt, other film damage... If there is dancing grain, the patch repair won't match )
    Last edited by poisondeathray; 25th Jan 2014 at 10:28.
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  12. I usually assume junk at the start or end of the clip is just decoding errors from the trim. I saw the defects at the end of the clip but ignored it.
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    It looks like de-graining is maybe what I need whatever. I assume proper de-graining is NOT simply blurring? But as you say it will assume the worst grain is picture. Yes most of the film is steady tripod shots, but there a few pan shots. Yes I did a composite at the end to hide a short fogging mark on the film. The thing is the film before sharpening is relatively grain free so there'd be no need for de-graining? So what I will try is put the UN-sharpened film through DESHAKER, then sharpen it later. Can you see any potential problem with that? But now I'm going out for a drink!
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  14. Originally Posted by timsky View Post
    So what I will try is put the UN-sharpened film through DESHAKER, then sharpen it later.
    Yes.

    Originally Posted by timsky View Post
    Can you see any potential problem with that?
    There are potential problems with everything! But deshaking before sharpening noisy material is a good place to start. You should also look at sharpening filters that try not to sharpen grain, often called edge enhancers. And use them sparingly.
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  15. Yes - proper degraining isn't simple blurring , but I doubt it will affect your deshaker results much

    My opinion - stabilizers that work like deshaker aren't suitable for these types of scenarios . Unless you can live with some residual wobble & shake - for a tripod scene, and desired rock stable results - what you usually want to do is "lock on" to some known static background element - say some bushes, or building in the background (buildings usually don't move much in the wind), etc... . Stabilizers like deshaker calculate the difference between subsequent frames but for the entire frame. What happens is it tends to drift especially if a big scratch appears or something like a car driving through the scene, foreground objects moving - can skew the calculations - because they are included as part of the frame. It will attempt to fix, and you get an overcompensatory motion in the wrong direction. You can adjust the "discard motion blocks" portion of deshaker , but usually you won't get perfect results in my experience

    Other stabilizers typically used for this scenario also calculate x,y, rotation similar to deshaker - but the calculation is usually in reference to a single frame in time per scene , over a selection area . So while there is more user input required (you define what is included and excluded), the results are perfect. Rock stable tracks are basically required for any compositing VFX work (such as your attempted patch repair) . With a rock stable track, you can fix the film defects (scratches, burns etc...) in a static scene with a single clean plate ; and even on a moving shot (where there camera motion), defects can be "patched" properly because you have good motion tracking data to match
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  16. BTW , if you feel that maybe the dirt/scratches and grain are interfereing with deshaker, but want to keep the grain/dirt/scratches version - what you can do is do the analysis on a heavily degrained/filtered/clean version, but apply the deshaker log results to the original version . Avisynth has some very good dirt/grain removal filters and techniques
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  17. VideoFred script for 8mm transfer http://forum.doom9.org/showthread.php?t=144271 has parts for every step in the process ( including only/and: stabilizing,denoising,sharpening,deflickering- Do I see it here?) and is very suitable for this kind of footage.
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  18. Stabilize before doing anything. The film damage won't interfere with stabilizing but I removed it afterwards anyway to keep the size down of the upload.
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    Some good tips. Thankyou all. Mephesto: That is almost perfect, certainly as good as I need. I'll report back when I've done more work.
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    I find AVIsynth's stab() an easier choice for film gate weave. Might face exactly the same issues though.

    Cheers,
    David.
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    I've tried stabilizing the un-sharpened version, here it is, it is much better than the sharp version, but still not as good as it should be. I used the default settings in Deshaker, different settings were worse.
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  22. Your video is still shaking. Put -1 in the motion smoothness, that keeps it to an absolute still (it still zooms but only in one direction). Stab() may or may not work better.
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    Thanks. Is -1 what you used? What were your other settings?
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    This is using full scale, all pixels, motion smoothness -1 on the un-sharpened version and its very good but not perfect
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  25. Oh, crop off the black borders before deshaking then add them later if you really need them. You probably could just set Deshaker to ignore certain areas but I don't have experience with that so can't say if it works.

    Also I forgot to tell you to make sure deshaker doesn't skip a single frame. You're at a static scene so there's no reason why it needs to skip anything. Skip frame if < 0% of blocks are fine.
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    Why crop off black borders? And replace them with what, white, green, parts of the picture?
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  27. Originally Posted by timsky View Post
    Why crop off black borders? And replace them with what, white, green, parts of the picture?
    Leave them cropped off for deshaker. All stabilizers work better if you crop off the borders first

    You can replace them with clean black borders after the stabilization
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  28. You can use the "ignore pixels outside" option in deshaker.
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  29. You can use Stabilise(), IMO is the best stabiliser out there, but it is underdeveloped and not ready to use. It's aimed at animation but maybe you can give it a shot. (edit: only on avisynth 2.58)
    Other than that I've found stab() to work better than deshaker. Deshaker is more aimed to "reduce" shaking rather than completely remove it as seen in my tests.
    Last edited by Dogway; 29th Jan 2014 at 14:19.
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    I have tried stabilising the same clip in Mercalli 3.0 and it is very slightly better. but Mercalli costs $250 whereas Videopad which uses Deshaker is only $30, So I'm hoping that by fiddling about with settings I can get Deshaker as good as Mercalli. I'll try and find stab()
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