Adobe After Effects Forum
Lip Sync Rig Not Working
Lip Sync Rig Not Working
by Dan McClelland on Aug 14, 2018 at 2:47:02 pm

In After Effects CC, I have created a mouth animation rig. Not my first, so I am familiar with the process. It is setup using a mouth comp consisting of the various mouth shapes, each one frame in length. In the animation comp, I use a null layer, moving it horizontally. An expression converts the x axis location to the appropriate frame. Typical mouth rig setup. I believe I learned it here.

On occasion, one of my mouth sounds will not match the corresponding location of my null mouth control. I first noticed this when playing back my character's mouth movements to verify it looks right. I noticed one of the frames, which was supposed to be the mouth for "L" was giving me "EH". The "EH" is the frame just before the "L". I figured I had just not moved my control far enough, but when I attempted to move it, the "EH" remained until it got to "OH", which happens to come right after "L".

I banged my head on the wall for about a day. Never did find a fix, but did notice that when I removed the keyframe right after the "EH" (which was supposed to be "L"), it changed back to "L".

I have other portions of my mouth animation in which the same combination of mouth sounds exist, and the "L" appears just fine. Also, it isn't consistent. In other words, it isn't always an "EH" in place of the desired "L". There seems no rhyme or reason.

Possible culprit? I did originally create the mouth comp as 12 fps, then changed it to 8. I did very little, if anything, using the 12 fps version. I made the change early on. Realizing that the fps settings need to be consistent, I thought I'd mention this in case it triggers a possible reason for this, uh, glitch. My mouth rigs, and my mouth shaped comp had been working well when I worked on AE 6. Went without the software for about a year, then recently subscribed to CC, which is when the problem seems to have started.

AE Compositor/Animator/Creator/Genius Extraordinaire (in my mind anyway)

Re: Lip Sync Rig Not Working
by Kalleheikki Kannisto on Aug 14, 2018 at 3:01:03 pm

Are you using hold keyframes? If not, it may be that that some of the keyframes are not aligned exactly to frames, i.e. they are between frames so as to throw off the precision, the slider value being close to but not exactly the expected value. This can happen when converting frame rates (or possibly even when outputting to a different frame rate, although not sure about that). Another possibility is keyframe interpolation if you're not using hold or linear. Viewing the slider values in graph view would tell you if this is the case.

Kalleheikki Kannisto
Senior Graphic Designer

Re: Lip Sync Rig Not Working
by Dan McClelland on Aug 14, 2018 at 6:37:49 pm

I am strictly using hold frames. And my mouth comp as well as main comp are both simply comps created with shape layers and a jpeg, no footage needing conversion to 8 fps.

However, in reading your responses, it reminded me of a little more detail that I was originally taught when learning to put these mouth rigs together. I was told to put the guide letters every 100 pixels and calculate the x position (which should at least be near to a multiple of 100), divide it by 100 and convert it to an integer. I had been dividing by 120 which I think I chose arbitrarily. Changing it to 100 doesn't seem to me to be a factor that would cause this problem. However, for the moment, it seems to have solved the problem.


Re: Lip Sync Rig Not Working
by Beth Levy on Aug 16, 2018 at 3:24:13 am

Hi Dan,

I've had this issue before with some slider-based lip sync rigs, even with a constant frame rate - and have found two quick fixes that worked for different jobs.

In your mouth shapes precomp, try checking this box:
Composition Settings > Advanced > Preserve frame rate when nested

Another option would be to add a Math.floor function to the slider or null driving your time remap expression, so that the slider only returns whole numbers.

Hope that helps!

Re: Lip Sync Rig Not Working
by Dan McClelland on Aug 20, 2018 at 5:54:31 pm

I thought I had this problem licked, and it's reared its ugly head again.

I've used all of the suggestions given. I've tried both Math.round and Math.floor which didn't seem to have any effect. I changed the setting for nested comps to maintain their frame rate, etc. It seemed one of the suggested changes fixed it. But alas, no.

This time I was watching for it to happen again. While I was syncing a character's lips, they each matched up initially as I moved the null controller. About half way through a sentence which finished with EE and EH mouth shapes, I played what I had so far and noticed the EE changed to EH. Thus I had 2 EH sounds together, as if my character were saying "uhhhhh". Maybe worth mentioning, the EH and EE are on consecutive frames in my mouth comp.


Re: Lip Sync Rig Not Working
by Dan McClelland on Aug 28, 2018 at 5:34:54 am

I just stumbled on another possible clue, as this problem hasn't gone away.

I had an animated conversation that was working properly. Then suddenly one of the mouth sounds was giving me "EE" instead of "AH". Then it changed back to "EE" which is what I wanted. It went back and forth a couple of times, and I couldn't figure out what was different or what I was doing to cause it to change.

Then I realized, when I zoomed in it went wrong. When I zoomed out, it went back to normal. Zoom, wrong. Zoom, right. How is this possible?


Re: Lip Sync Rig Not Working
by Walter Soyka on Aug 28, 2018 at 9:20:04 am

[Dan McClelland] "Then I realized, when I zoomed in it went wrong. When I zoomed out, it went back to normal. Zoom, wrong. Zoom, right. How is this possible?"

Clear your cache. Edit > Purge > All memory & disk cache.

Walter Soyka
Designer & Mad Scientist at Keen Live [link]
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
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