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Phil
04-23-2004, 01:00 PM
I know that it is possible to simply clone images and alter the start frame & then use a stack of image maps to get a similar effect, but it seems very odd that motion blur doesn't take into account applied image sequences.

I have no idea if this works in 8.0 because there is no published list of resolved issues (still!) and there is unlikely to be another patch to 7.5 (despite the need for it).

If necessary, I can provide example content on request to demonstrate this problem, but it should be simple enough - stick an image sequence as a colour texture map on a plane, turn on motion blur, render.

Mylenium
04-23-2004, 01:14 PM
What are you getting at? You cannot motion blur image sequences (not physically correct, that is) with temporal oversampling - it only evaluates how existing pixels would blend inbetween frames. The best you can get is some ghosting effect. The only thing that could overcome this weakness (in part) would be something along the lines of ReVision Effect's ReelSmart Motionblur (interpolating/ extrapolating pixel based motion vectors) but this method is rather computationally intensive and does not work too well with extreme situations. I also doubt The LW team would be implementing such functionality. Sorry buddy, but it seems that for the foreseeable future you wil have to delve somewhat deeper into compositing programs and prepare your image sequences there...

Mylenium

Phil
04-24-2004, 08:25 AM
Originally posted by Mylenium
What are you getting at? You cannot motion blur image sequences (not physically correct, that is) with temporal oversampling - it only evaluates how existing pixels would blend inbetween frames.

Mylenium

Not that I particularly care for the underlying reason, it seems daft to have this current limitation. As I said, I can work around it to some limited extent, but it would be nicer if LW could figure it out in some fashion, after all it knows that is is going to apply motion blur and the number of frames over which it is to calculate the blur. It wouldn't be beyond the wit of man to then look at the image sequences and apply the blur as necessary.

BTW, I love the attitude. Nice. Keep it up.

Karmacop
04-24-2004, 09:40 AM
Really, motion blur on 2d images is hard to do, and completely different to 3d motion blur. Also, it's more suited to compositing apps etc. There's no way this feature will ever get into lightwave.

Lightwolf
04-24-2004, 10:13 AM
Phil:
like the others have said, a "ghosting" type motion blur would be possible, and I actually see a couple of uses for that myself, it would be quite neat.
Baiscally for every antialiasing pass LW would have to look at the image sequence, find the current, next and previous frames and weigh them together before they get applied as a texture.
Shouldn't be hard to do, I guess it is more a matter of priorities than anything else. AFAIK plugins can't access image sequences out of order, so writing one wouldn't circumvent the problem either.
Procedurals of course have full motion blur, since the animated parameters get re-evaluated for every sample in time.

"Real" motion blur would of course be out of the question, not only because that is something better left for a compositing app, but also because that would slow down rendering significantly (imagine LW evaluationg motion vectors for a series of images for every rendering pass, that's like an MPEG encode of roughly 3-5 frames per render pass !).

Cheers,
Mike

probiner
02-16-2010, 03:14 PM
Nothing new about this subject?
I am working on a piece where i use an image sequence and want the elements in it, to blur with the action.

Cheers

Captain Obvious
02-16-2010, 03:32 PM
This thread is really old!

If you want to apply motion blur to image sequences, buy ReelSmart Motion Blur. It works quite well.

http://www.revisionfx.com/products/rsmb/

probiner
02-16-2010, 03:58 PM
Thanks Captain Obvious, that plug looks great. But thats a video effect for a compositer, right? Will it be applyed in LW render? :stumped:

Here is my usual model with the idea roughly applyed . I want those stripes to be blured in render time. Well i could blur the animation, yes, but the distance each travels is different in the 3D model.

http://i153.photobucket.com/albums/s202/animatics/Lightwave/UV-STRIP-ANIMATION_render_e-1.gif

Well, probably going to stick with a simple solution, and not going to be picky; just wondering if there were any improvements.

A procedural will be blured right? I'll try 2D Grid.

Cheers

Lightwolf
02-16-2010, 06:02 PM
A procedural will be blured right? I'll try 2D Grid.

Only if you render with steps, a simple Photorealistic Blur will not do.

Cheers,
Mike

probiner
02-16-2010, 06:20 PM
Steps as in "Motion Blur Passes", right? Yes it seems to work. Thanks.

Lightwolf
02-16-2010, 07:36 PM
Steps as in "Motion Blur Passes", right? Yes it seems to work. Thanks.
Yes. Great :D

Cheers,
Mike

Captain Obvious
02-17-2010, 02:10 AM
Steps as in "Motion Blur Passes", right? Yes it seems to work. Thanks.
With the perspective camera, the normal anti-aliasing and the adaptive sampling both work on motion blur caused by camera or geometry movement, but neither will produce motion blur with things like shadow mapped spotlights or procedurals with animated parameters. The 'passes' option is useful to blur these things, and it works perfectly fine in conjunction with regular anti-aliasing and adaptive sampling as well. If you render a scene that doesn't actually have any motion, it will look the same with 10 AA samples, no adaptive sampling and 1 pass, as with 1 AA sample, no adaptive, and 10 passes. The passes option helps with anti-aliasing as well, you see! :)

probiner
02-17-2010, 07:09 AM
@Captain Obivous.
Well MB settings is not my issue right now. But i think i understand what you say. But you still have to use AAx4 at least if you have fine line details, otherwise you wont give AS enough data to work with, right? Cause every MB pass will have it's own AA solution. But yeah, if the whole thing is blured it probably makes no harm to go with AAx1, since you can't see detail.
_____________

My issue now is to make the the lines slide over the UV stripes. I'll try to be clear on my attemps so far.

1-I tryed Larry's trick, to use Textured Filter ( in the Image Editor's "Processing Tab") over a blank image with Grid animated position and with "Animate Filters" ON.
MB did not evaluate Grid's animation, so everything stood still.

2-I can apply Grid to a UV with Grid 2D Node, but then since i'm using UV i cant animate the Position... Is there a way to displace a single UV cordinates?

3-I tryed to use the UV Morphing trick (http://www.newtek.com/forums/showthread.php?t=85719) making a copy of each UV and make it slide between 0% and 100% in the U axis.
MB works, but i don't know why LW renders the UV strips with "triangular bleeding" like you can see below in 2nd image... =(

http://i153.photobucket.com/albums/s202/animatics/Lightwave/th_issue_02_b.png (http://i153.photobucket.com/albums/s202/animatics/Lightwave/issue_02_b.png) UV morph along the image strip

http://i153.photobucket.com/albums/s202/animatics/Lightwave/th_issue_01.png (http://i153.photobucket.com/albums/s202/animatics/Lightwave/issue_01.png) The issues with nodes using a blank white image.

Thanks for baring with me guys. I'm about to just blur the video and go with that...

Cheers

(yay i learned to post thumbs and not gigantic images...)

probiner
02-17-2010, 10:52 AM
Ok, there's a much easier solution for this particular case where i just want to slide stuff over a loop. Just need to use the "U Offset" input in the Image Node.

Now i still have those bad triangles out of model's freeze. Anyone can give me a hint of what is the problem?
I tryed to mask them out with a Vertex Color Map, but still some go through that.

http://i153.photobucket.com/albums/s202/animatics/Lightwave/th_MB_0.png (http://i153.photobucket.com/albums/s202/animatics/Lightwave/MB_0.png) my oh my... why does the texture is linked to the wrong triangles? UV map fail?
http://i153.photobucket.com/albums/s202/animatics/Lightwave/th_MB.png (http://i153.photobucket.com/albums/s202/animatics/Lightwave/MB.png) vertex color map helped, but the problem persists.

Cheers

probiner
02-17-2010, 12:14 PM
So the blur works now and i'm very happy with the test result.

http://i153.photobucket.com/albums/s202/animatics/Lightwave/UV-STRIP-ANIMATION_render_f.gif

There are still bad lines showing up. You guys have no clue how do i solve that? :bangwall:

Cheers

EDIT: ok, with the help of zardoz :beerchug: i think i've found the source of the problem: UV Spider. I'll post something if i come out good from this.