Animating a character’s mouth talking in any form of animation is one of the more time consuming jobs of character animation. Particularly if your project is dialogue heavy or your character has the urge to sing.
Fortunately auto lip syncing in many animation software studios is becoming more common and is helping to speed up the lip syncing process. Reallusion’s Cartoon Animator is no exception with a fairly good auto lip sync feature. I made a tutorial video demonstrating how to auto and manual lip sync in Cartoon Animator here.
However auto lip sync is not perfect (yet) so you’ll definitely find yourself manually lip syncing a character at some point. Or maybe you just prefer to manually lip sync yourself because you like that level of control.
Whatever the reason here are Six tips to help improve your lip sync and to stop you getting bogged down into really small details that literally do not matter for the amount of screen time they’ll get.
1. Auto Lip Sync is NOT as Bad as You Think
Auto lip sync is not as bad as you think. If you give it clean audio it’ll usually work pretty good. If you’re feeding in a voice track that includes background noises or music that’s on you, it’s not the auto lip sync’s fault.
Even with clean audio it’s never perfect by any means, but you really only need to fix the obvious mouth shapes that jump out at you as being incorrect.
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Cartoon Animator’s Automatic/Manual lip sync tools are pretty straight forward and easy to edit. |
2. You Do Not Need to Animate Every Syllable of Every Word
You should make the title of this second tip a mantra. You do not need to animate every syllable of every word with the correct mouth shape.
When we speak our mouths do not form the shape of every single syllable in a word. If you change the mouth shape for every syllable the lips will move too fast and look unrealistic – especially if your character is talking at a casual pace.
3. Animate ahead of the audio
Start a mouth shape one or two frames before you hear the sound (sometimes even more as a character anticipates their speech before making a sound) for more realism. Because the sound is being made by the mouth we usually see the mouth move a split second before we hear the voice coming from it.
4. Pay Attention to the Closed Mouth Shapes
Lip syncing is as much about timing when the mouth is closed as when it is open. The closed mouth shapes can often be more important than the open shapes because you really notice if a character is making a B, F, or P sound and the actual mouth is open. It just looks wrong.
5. Be Your Own Reference
This is a really obvious tip but if you’re not sure of a particular mouth shape for some dialogue, grab a mirror and watch yourself form the mouth shapes. Speak normally, don’t emphasize the syllables (unless your character is doing this). If you have a phone camera handy you may even like to record yourself so you can replay your mouth over and over as you work.
6. Exaggerate the Mouth Movement
Once you have the general lip sync done and it’s looking pretty good, take another look at it and see if you can make it more dynamic.
If a character is showing emotion that is partly expressed through the mouth, maybe they’re angry and shouting, open the mouth a little wider, show more teeth.
If, like Cartoon Animator, your animation software uses a standard set of mouth sprites, and you don’t always have access to variations on those sprites, try using Free Form Deformations (FFD) to make the mouth and jaw line more flexible and expressive.
You do not need to animate every syllable.
Lip syncing is time consuming enough. Animating every syllable is a rookie mistake. Honestly I’ve seen long time animators make that mistake and, watching their characters talk feels like you’ve run a small marathon.
But don’t take my word for it. Here’s a video of former Disney Animator, Aaron Blaise giving you his tips on lip syncing (fast forward the video a few minutes – after all his promotional waffle – it’s an old video from nine years ago, before people knew to get straight to the point).
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