More often than not, CG lip sync suffers from being 'floaty' and lifeless. I feel that clay animation is usually much snappier and livelier, due largely to the use of straight replacements. With replacement animation, one mouth shape is completely removed from the face and replaced with another different one, which is then sculpted over a few frames before being replaced with another mouth shape. It's this liveliness that I've tried to recreate using Maya's blend shapes.
In the next few pages I'll show you my lip synching workflow. It's by no means a way of doing hyper-realistic mouth animation but, at the same time, I do make an effort to make it accurate. The tips and methods you'll read about are ones that I've picked up and adapted in my time at Aardman.
One of the first jobs I had was animating a CG version of a scene from Chicken Run because Aardman was investigating the possibility of a straight-to-video sequel. It didn't happen, but by painstakingly copying the chickens' every move and beak shape, I really learnt a lot about the Aardman technique. The sort of lip sync I do is more suited to stylised or cartoon characters and, as such, is quite caricatural - some good examples are the UK's BBC3 'Blobs' idents or the Creature Comforts series. But even if it's not your cup of tea, I still think most people will learn a lot about lip synching and character animation in general by following this tutorial. This isn't a beginners' guide, so I will be assuming that you have some previous animation experience: rather than explain the process in minute detail, I'll be covering the key points, then leaving you to work out how to put them into practice for yourself.
In the files below, you'll find four scenes and a movie of the finished animation. The first scene is the character without any animation, all ready to go. The second is how it looks once I've done the bulk of the animation using the Blend Shape sliders. The third pass shows how it looks once the Curves have been adjusted in the Graph editor, and the final scene includes head movements. Feel free to use my character to work through the tutorial the first time. Once you complete it, have a go with one of your own characters - you'll learn just as much again!