-
Motion “stutter” – how to fix
Hi there.
Currently dealing with a project that was created using a series of “camera moves” inside Maya, and mastered in After Effects. Essentially, the project came to me as one finished QT file, that we then ran through Final Cut for some quick color corrections, then through Compressor and DVDSP for a master DVD.When playing the disc, however, some areas exhibit a “stutter” during lateral movements in the animations (especially the faster moves). I expressed to the client that the reason behind this could be:
1. We’re showing a progressive scan DVD on an interlaced screen via a connection that does not allow for progressive scan connection (DVD player is not progressive scan). In essence, fields are being added to the image, creating this occasional stutter.
2. There may be something that can be changed inside Maya or AE that will minimize this stutter. Adding fields or 3:2 pulldown perhaps? This part, however, I am unsure of, and wonder if it’s out off my hands.
I personally feel that it’s best to leave it as a progressive scan image and try to only play it back on better screens and DVD players. But the client is insisting that the stutter be removed or minimized. As their Online Editor and DVD Author, is there anything I can do?
(The reason I posted here is because I’m not quite sure where else to add this post)
Thx
Aaron H. -
3 Replies
-
Well, I’m one of those guys who believes that the stutter or “judder” is unavoidable, given a progressive frame rate and a medium-speed lateral move. It’s an optical phenomenon, where the persistence of vision breaks down because the move is regular enough that our eyes can discern each frame. That’s the theory, anyway.
(If you have the Bourne Ultimatum DVD, check the aerial bridge shot after the “Gilberto de Piento, your party is waiting” scene. Yikes!)
I don’t think that fields are being added to the playback, if anything, they might just soften the image, but to be honest, I don’t know much about what DVD players do to movies.
In my opinion, if you have to keep the direction and pace of the move, you should render at 60 fps in Maya, bring that into AE and render 29.97 interlaced to smooth it out. It has to be done way back in Maya, since you need to actually create new frames for this to work.
Having said that, if you have Twixtor, you could create the extra Maya frames in AE, then render that as interlaced. With a lateral move, it should work.
Anybody else?
-
[Aaron D Hose] “I personally feel that it’s best to leave it as a progressive scan image and try to only play it back on better screens and DVD players.”
“Progressive” in MPEG-2 is still made up of 2 fields, they just happen to be from the same frame. If you render your footage at 23.98 fps and encode it properly (Apple’s Compressor should do this automatically, other programs you may need to flip a switch) then your footage will be presented as 23.98 ‘progressive’ if the DVD player’s progressive mode is turned on, and will automatically have a 3:2 pulldown added by the DVD player to make the footage 29.97 interlaced if it is not.
Darby Edelen
Designer
Left Coast Digital
Santa Cruz, CA -
[Aaron D Hose] “2. There may be something that can be changed inside Maya or AE that will minimize this stutter. Adding fields or 3:2 pulldown perhaps? This part, however, I am unsure of, and wonder if it’s out off my hands. “
This is a common topic around here, probably on every AE/Maya/DVD forum. I’ve been reading these threads for years and have found no clearly consistent answer. Seems to be a question of experimentation. But since there are so many variables and different people and applications involved, your experiments have to be carefully designed and vetted.
The big animation hosues don’t seem to have these problems. They’ve developed their workflows to take advantage of every aspect of the pipeline including minimizing the number of fields/frames required (lower costs) and adding motion blur to hide artifacts that will inevitably creep up during the MPEG2 transcode.
bogiesan
This is my standard sigfile so do not take it personally: “For crying out loud, read the freakin’ manual.”
Reply to this Discussion! Login or Sign Up