I've got a short but ambitious project that relies on rotoscoping.
I hope to complete it as vector animation, but right now I'm still working on feature extraction using PhotoShop filters.
Overall, the result is compelling, but I find that no matter how carefully I try to be strictly consistent from frame to frame, almost any editing of the images results in flicker.
What's the best way to keep my edited images flowing smoothly?
Avoid flicker?
Moderators: Víctor Paredes, Belgarath, slowtiger
I need more information to give a helpful answer. Which element is flickering? Do you mean a flicker like "different brightness from frame to frame", or do you mean "edges of objects will wiggle between frames"? Is the whole image flickering or just some part? Could you perhaps post two pictures: of the source material and the same frame after rotoscoping?
I agree with St on this one, can we have more information or sample frames: I have done a lot of rotoscoping, both from 35mm film and from video. In this case it sounds like an interlace problem. If you have access to combustion, then use the de-interlace tool in the video options to seperate the fields/read only one field. This generally resolves any flicker problem.
But more info will help us.
Rhoel
But more info will help us.
Rhoel
Yes, of course you would need to see what I'm doing...
I've attached a before and after.
It's the blemish removal on step 2 that is causing slight flickers at the erasure edges, due to the fact that the blemishes (naturally) track the face.
So the question, expressed more clearly, is: how do I get my erasure envelopes to accurately track from frame to frame?
Getting this right is important because of the sheer subtlety of the facial animation here--incredibly subtle, in fact.
Yeah, this is facial animation--I made it in iClone!
I've attached a before and after.
It's the blemish removal on step 2 that is causing slight flickers at the erasure edges, due to the fact that the blemishes (naturally) track the face.
So the question, expressed more clearly, is: how do I get my erasure envelopes to accurately track from frame to frame?
Getting this right is important because of the sheer subtlety of the facial animation here--incredibly subtle, in fact.
Yeah, this is facial animation--I made it in iClone!
I think what you're asking is very difficult, because it's impossible for a filter to know what the picture is supposed to look like if it's only looking at one frame. But, you could try running a temporal smoother on the cleaned-up frames as a sequence. A temporal smoother will look for similarities over a sample series of frames, and discard most of the things that don't match as "noise."
Thanks for your comments.
I suspect that slowtiger and touched are both right.
Touched, I'm going to try to see whether I learn how to use a temporal filter in AviSynth and then see whether it helps.
Slowtiger, I'm still resigned to committing myself to the tedious work you describe if necessary ...
If anyone else has some insight, share...
I suspect that slowtiger and touched are both right.
Touched, I'm going to try to see whether I learn how to use a temporal filter in AviSynth and then see whether it helps.
Slowtiger, I'm still resigned to committing myself to the tedious work you describe if necessary ...
If anyone else has some insight, share...
OK, now I've found one approach to the problem: rather than painting on every frame by hand (which was doomed to fail), I created a single mask, which I pasted as a new layer on each frame, using the batch-processing feature of Paint Shop Pro.
This provides noticeably less flickering, but was not the complete solution I hoped for.
Therefore I turned to Touched's suggestion, and found the Temporal Cleaner for VDub.
At a high setting for Luminance cleaning (200 out of the max, 255), it further reduced the flicker.
Anybody want to see an animated GIF of the face?
This provides noticeably less flickering, but was not the complete solution I hoped for.
Therefore I turned to Touched's suggestion, and found the Temporal Cleaner for VDub.
At a high setting for Luminance cleaning (200 out of the max, 255), it further reduced the flicker.
Anybody want to see an animated GIF of the face?
Just a month ago the NY Times had an article online about linklater with screenshos and model sheets from his work. Unfortunately you can't access that anymore, at least not for free.
Basically the process consisted of scanning, filtering, vectorising, as everbody would do. Then artists had to clean and straighten the lines frame by frame, erasing little spots like those which would appear in the beard, and sometimes draw (and really animate) additional lines. For this they had model sheets of each character with notes about how it should look like. The amount of work was incredible, IIRC they said something about 80 hours per second of film, although this number seems to be a magnitude too high to me.
Characters like in your example would perhaps look better if they are rotoscoped in the traditional way, that is, drawn over in a bitmap animation program like Mirage.
Basically the process consisted of scanning, filtering, vectorising, as everbody would do. Then artists had to clean and straighten the lines frame by frame, erasing little spots like those which would appear in the beard, and sometimes draw (and really animate) additional lines. For this they had model sheets of each character with notes about how it should look like. The amount of work was incredible, IIRC they said something about 80 hours per second of film, although this number seems to be a magnitude too high to me.
Characters like in your example would perhaps look better if they are rotoscoped in the traditional way, that is, drawn over in a bitmap animation program like Mirage.
st wrote:
"Characters like in your example would perhaps look better if they are rotoscoped in the traditional way, that is, drawn over in a bitmap animation program like Mirage."
At first, I was inclined to disagree, because my own experience demonstrated clearly that moving from individual frame retouch to repositioning a single mask across all the frames improved the results...
...but as you may already realize, we really don't have any "results" at all yet, because I haven't yet vectorized a series of frames (rather, only two test frames at this stage).
What I believe you're thinking, but didn't explicitly say, is that the vectorizing process will happen outside of my control, and is liable to introduce a significant unpredictable variations, frame to frame.
Therefore, what I suspect you're thinking is the way to get consistent vector results is to further simplify my shapes at this stage.
Or are you saying that I had better avoid vectorizing altogether?
[ I should probably try to get the NY Times article from the online database at my local library.... ]
"Characters like in your example would perhaps look better if they are rotoscoped in the traditional way, that is, drawn over in a bitmap animation program like Mirage."
At first, I was inclined to disagree, because my own experience demonstrated clearly that moving from individual frame retouch to repositioning a single mask across all the frames improved the results...
...but as you may already realize, we really don't have any "results" at all yet, because I haven't yet vectorized a series of frames (rather, only two test frames at this stage).
What I believe you're thinking, but didn't explicitly say, is that the vectorizing process will happen outside of my control, and is liable to introduce a significant unpredictable variations, frame to frame.
Therefore, what I suspect you're thinking is the way to get consistent vector results is to further simplify my shapes at this stage.
Or are you saying that I had better avoid vectorizing altogether?
[ I should probably try to get the NY Times article from the online database at my local library.... ]
The article was OK, but the examples had been made into a Flash movie, so chances are that a print edition won't help you much. Unfortunately I only saved two stills from the film - I didn't expect the article to vanish that fast.I should probably try to get the NY Times article from the online database at my local library....
Rotoscoping in general has to deal with a heap of problems. Some are:
- it's hard to identify the outline of a character if the source material wasn't shot against a plain background
- any automatic process like vectorising has to fight with moving and disappearing shadows, mainly in the face
- same is true for features like stubbly beards, wrinkles in clothing etc.
If you want your result to have a smooth, non-flickering look, you could:
- rely on filtering, applying the very same filter settings to every frame, and use something like "posterize" - means the rotoscoping wíll be bitmap-based
- vectorize your stuff, then choose "keys" and interpolate between them - needs a lot of cleanup because the number of points must match. AS can't do this, I don't know if software with this ability exists
- build a model of your character in AS, identify the keys of your source material, adjust the character model to these frames, interpolate - this will be the smoothest, but you may experience odd shifts and morphs.
But if you accept the flickering, you can make it an artistic statement. Not long ago I saw a film with crude rotoscoping where the characters had been coloured in a nice, sketchy way - it flickered, but that fit the background and the story. The probably most prominent example of flickering rotoscope was featured in the film "Yellow Submarine", here's a clip from that sequence: http://youtube.com/watch?v=A7F2X3rSSCU. They used footage of Fred Astair and Busby Berkely, traced roughly the outlines in black, then painted it with stiff brushes, changing colours, deliberately ignoring the traced outlins. I like the result a lot. If you want to do something like this, a bitmap based software is better for the job than AS.
In any case, don't decide befor you haven't done a test of at least some seconds in your intended workflow.
I can surely vouch for what slowtiger said. I rotoscoped my entire AS contest animation. 30 seconds worth. For the mostpart the characactors went fairly smoothly. But as you can see in the closeup face, I had a lot of flicker problems. I did some research after the fact and found this to be a problem with rotoscoping. I did all my rotoscoping in AS with vector points and as mentioned above I had a lot of odd shifts and morphs. Needless to say, I spent hours tweaking. Had I know what slowtiger just said about rotoscoping I may not have done what I did with my animation. But on the other hand I could not have done some of the more complicated animation moves that I used in my animation. So, it was a trade off for me. From all I learned doing the project I would say it was well worth the time and effort. However, I will try to plan more carefully next time.Rotoscoping in general has to deal with a heap of problems. Some are:
- it's hard to identify the outline of a character if the source material wasn't shot against a plain background
- any automatic process like vectorising has to fight with moving and disappearing shadows, mainly in the face
- same is true for features like stubbly beards, wrinkles in clothing etc.
- vectorize your stuff, then choose "keys" and interpolate between them - needs a lot of cleanup because the number of points must match. AS can't do this, I don't know if software with this ability exists
- build a model of your character in AS, identify the keys of your source material, adjust the character model to these frames, interpolate - this will be the smoothest, but you may experience odd shifts and morphs.
In any case, don't decide befor you haven't done a test of at least some seconds in your intended workflow.
My rotoscope video.
http://homepage.mac.com/rplate/iMovieTheater12.html
I can surely vouch for what slowtiger said. I rotoscoped my entire AS contest animation. 30 seconds worth. For the mostpart the characactors went fairly smoothly. But as you can see in the closeup face, I had a lot of flicker problems. I did some research after the fact and found this to be a problem with rotoscoping. I did all my rotoscoping in AS with vector points and as mentioned above I had a lot of odd shifts and morphs. Needless to say, I spent hours tweaking. Had I know what slowtiger just said about rotoscoping I may not have done what I did with my animation. But on the other hand I could not have done some of the more complicated animation moves that I used in my animation. So, it was a trade off for me. From all I learned doing the project I would say it was well worth the time and effort. However, I will try to plan more carefully next time.Rotoscoping in general has to deal with a heap of problems. Some are:
- it's hard to identify the outline of a character if the source material wasn't shot against a plain background
- any automatic process like vectorising has to fight with moving and disappearing shadows, mainly in the face
- same is true for features like stubbly beards, wrinkles in clothing etc.
- vectorize your stuff, then choose "keys" and interpolate between them - needs a lot of cleanup because the number of points must match. AS can't do this, I don't know if software with this ability exists
- build a model of your character in AS, identify the keys of your source material, adjust the character model to these frames, interpolate - this will be the smoothest, but you may experience odd shifts and morphs.
In any case, don't decide befor you haven't done a test of at least some seconds in your intended workflow.
My rotoscope video.
http://homepage.mac.com/rplate/iMovieTheater12.html