GenMotion and DePan plugins for global motion compensation

[scharfis_brain]

there will be A/V async.
remove assumfps and it will be okay.

[oddball]

Hey guys I need some help. I really cannot understand why it's so difficult to fix this problem. I have a movie clip that moves up and down by a few pixels every few frames (Something like every 15 frames but not always). I just need to stablize the up down motion. I thought it would be simple but it appears not.

The depan command I tried was

i = ConvertToYV12()
mdata = DePanEstimate(i)
DePanStabilize(i, data=mdata, dxmax=0)

But the frame moves up and down by mad amounts every few frames.

In another thread someone suggested I use a cropped clip for motion estimation and apply that to the second clip or somesuch. Damned if I know what he means. The clip has a logo on it that I could use as a guide to help with the motion detection. Since that logo is the same all the way through the clip and it too moves up and down every few frames I thought it would be a matter of applying a filter that detects that area when it moves up and down.

I don't know very much about all these Avisynth commands apart from the basics. The Depan manual seems rather cryptic to someone who does not do much Avisynth work.

Can someone lead me to a solution?

Thanks.

EDIT: OK I tried something from some earlier postings. It seems to work a lot better. No wild motion with big frames appearing this time. Is this OK?

i=ConvertToYV12()
r=1
mdata=DePanEstimate(i,trust=4,range=r)
DePanInterleave(i,data=mdata,prev=r,next=r,mirror=15)
SelectEvery(r+r+1,r)
i=last
mdata=DePanEstimate(i,trust=4,range=r)
DePanStabilize(i,data=mdata,cutoff=1,prev=1,next=1,mirror=15,dxmax=0,dymax=0)

Awwww crap. Just realised it did nothing to stop the up and down motion. Back to square one.

Nope. I think I nailed it. It needs a few frames to figure out the motion then it stabilizes it rock solid. I removed what looks like a repeat line from that code too.

EDIT: Well it does not seem to stop the very slight up and down motion every few frames at all. Very frustrating.

[oddball]

Originally Posted by Beave

I'm getting closer to solving my problem. I used this script to first analyze only the bottom border:

mpeg2source("test_720p.d2v")
Trim(0,400)
i = ConvertToYV12()
j = ConvertToYV12().crop(0,712,-0,-0)
mdata = DePanEstimate(j,info=false)
DePanStabilize(i, data=mdata, dymax=1, dxmax=0, info=true)

Now I can see the data being diplayed on the video. the "dy" is either between -0.15 and +0.10 or between +0.25 and +0.55 when the video jumps. Now I now the values, but how do I translate that into my DePanStabilize function? So I have the sweet spot at around 0.18 and I want the picture to shift one pixel up when going over that threshold. How do I do that?

Thanks for the help in advance!

Same problem. Fizik how do I compensate for a vertical dy = 0.01 to 0.04 pixels frame motion?

Here is a screenshot of DePanStabilize output.

http://img213.imageshack.us/img213/4462/motionpm8.png

[Fizick]

Please do not cross-post.
Are your source is progressive? If yes, here is the steps:

1. find appropriate crop values to remove almost all besides logo. Not crop logo at any frame. And use cropped width and height as power of 2 (i.e. 16, 32, 64, 128, 256)

mpeg2source(...)
c=crop(100,200,300,400)
return c

2. Try analyse the motion
mpeg2source(...)
c=crop(100,200,300,400)
m=depanestimate(c, dx=0)
depan(last,data=m, info=true)

(logo is very small to use directly depanestimate(c, info=true))

(You can also produce log file to analyze and process it somehow)

dy = 0.01 to 0.04 pixels is very very little values
Probably you will get around 3.0 to 10.0

Chack scenechange too.

4. Next step is stabilization.
mpeg2source(...)
c=crop(100,200,300,400)
m=depanestimate(c, dx=0)
depanstabilize(last,data=m, info=true,cutoff=2)

Try tune some parameters, for example cutoff

But I am not sure that DepanStabilize can give usable result for your case. (NO WARRANTY )

[oddball]

When I open up the Avisynth in Vdub I get an error.


Script error:depanestimate does not have a named argument "dx"

I am using 1.9.0. dx=0 does not work.

[Fizick]

NO WARRANTY

may be dxmax ? (I did not try it)

[oddball]

Originally Posted by Fizick

NO WARRANTY

may be dxmax ? (I did not try it)

Hey it's your plugin lol

Oh well looks like the warranty is void. Depan simply cannot deal with small vertical movements. Thanks anyhow.

[Fizick]

I did not try that script right now...
(ones upon a time i tested similar)

what dy shift have you got?

[oddball]

It shifts between 0.01 to 0.04 up and down. Using the logo was no good. Depan was not sensing any movement on it. If I use the previous posters line 712 which is pretty much where my bottom border is then it detects the small motion up and down. It detects it but DepanStabilizer cannot move the frame by such small increments up and down to correct the vertical motion.

[Fizick]

I am sure you still do get right settings for Depanestimate.
What is real shift?
0.04 pixels is invisible.
Post your real script like it:

mpeg2source(...)
c=crop(100,200,300,400)
m=depanestimate(c, dxmax=0,info=true)

And why you do not use v1.9.1 ?

[oddball]

I initially tried

DirectShowSource(video.m2v)
c=crop(1058,570,76,80)
m=depanestimate(c, dxmax=0)
depanstabilize(last,data=m, info=true,cutoff=2)

But it does not detect any movement whatsoever where the logo is (It is correctly set as i can see the logo only when I add 'return c').

So I tried.

c=crop(0,712,0,0)
m=depanestimate(c, dxmax=0)
depanstabilize(last,data=m, info=true,cutoff=2)

Like a previous person used and it detects the movement and displays it in Depan's output but it does not stop the movement up and down.

I am using 1.9.1 now. No difference though.

[oddball]

Would it be helpful if I uploaded a clip from the movie for you to look at?

[Fizick]

Logo is not moving or depanestimate do not detect its movement?

upload short compressed clip.

[Fizick]

if movement between frames is always really so little, and it slow accumulates to large values, then some new specific algorithm must be implemented (for example, motion estimation across large interval). But I have no plan to do it right now.

[AVIL]

Hi,

A mad idea. If you suffle the frames, do depaning and reorder it ¿could result?.

As example:

a=clip.selectevery(10,0,5,1,6,2,7,3,8,4,9)
v=a.depanestimate()
d=a.depanstabilize(v)
d.selectevery(10,0,2,4,6,8,1,3,5,7)

[scharfis_brain]

I get some weird greenish tint when I try to use depanstabilize at default values.

It is best noticable with greyscale videos.

Is this issue known?

[odyssey]

I have trouble writing a log file. What's the correct syntax for it?

I'm trying to stabilize some of the very old disney shorts, which are badly transferred resulting in a very jumpy clip. Base frames seems to be detected quite well, but i'm not so happy with the correction itself. I've been tweaking some of the parameters with different results. My main concern is that when i specify dxmax/dymax in both DePanEstimate and DePanStabilize, there are still cases where it corrects with insane values.

I dislike that it focuses so much on the center, because it appearently often detects a moving character as a reference instead of the actual scene.

I don't really understand the way this works. I would expect it to take the base frame and use that frame as a reference for correcting other frames, but as I understand, it only corrects based on the range, that is the surrounding frames (is this correct?).

Can someone enlighten me? Also I don't understand the meaning of parameters cutoff, damping and trust.

[odyssey]

Bump. Could someone please clear up my confusion in the last post?

[DarkT]

Can't help you there, but I share your pain - I messed with the whole stabilization thingy for a couple days, and gave up on it - no matter the settings, sometimes it messed up big-big, detected stuff incorrectly, and so on... The only solution I got to was use really small values, and then record frames where it mis-detects, and then, theoretically, not apply it to those places... Which is all too much work then I'd care to do, so I dropped it...

Edit:

In case you wonder what I mean by small values, here's what I used:

i = ConvertToYV12()
mdata = DepanEstimate(i,dxmax=2,dymax=2,range=3,stab=1.0)
DePanStabilize(i, data=mdata)

[johnmeyer]

If you don't mind using Deshaker instead, it does a VERY good job of motion stabilization, if that is the only thing you need to do. I wrote a very detailed guide several years ago which you can find here:

http://www.sundancemediagroup.com/ar...aker_guide.htm

It was then ripped off and posted at dozens of other places around the Internet, so you can easily find it elsewhere (in case you have problems linking to the above site). Just Google my name and "Deshaker."