under normal circumstances the duration of a blink of the human eye is nearly constant.
But the pause between is not and it is highly dependant of the situtation,
The problem is: How can I animate this more or less parametrized without the need to animate each single blink of each single character for the whole animation by hand.
What I tried and what didn’t work was:
Create one strip of the blink itsself and add a second strip, with an dummy animation after it. Via driver animate the playback speed of the dummy animation. Now the pause after the blink is parametrized.
Make a Meta from both strips. Repeat the meta. Now animate the playback speed. Nope. The animatable playback speed now has become constant,
Wouldn’t it be easier if you just duplicated the blinking keyframes and placed them on uneven distances on the timeline? And after you get one character done you could copy paste all the blinking keyframes to other characters and offset them so they will have a different timing? Then do corrections where needed?
“Manually creating a blink animation” can mean a lot of things. I understood your original problem being that you are now going through the animation, pausing on each blink moment, then selecting the eye bones (or shape keys, if you are using them for animating), then adding a keyframe to them, then going forward into the frame that the eye should be closed, posing it closed, adding a keyframe, then going forward to the frame it should be open again, opening it, then adding a keyframe. And then doing all this every time you want the character to blink.
That would definitely be frustrating. That’s why I instructed to just create one blink, then selecting the keyframes and duplicating them a few times, and then duplicating the whole blinking sequence a few times to get a long generic blinking sequence. That would take about 30 seconds to do. And after getting it right once you could reuse it for all of your animations by just offsetting it according to the situation, and adjust some blinks manually if they happen to be in wrong moments. I really don’t see any benefit in spending days to seek a way to make this automated, as it’s rather simple to do manually. Unless it’s more about the technical challenge of it that you are interested in trying to resolve. I don’t think anybody would even notice that the blinkings of the characters follow the same pattern, especially if that pattern is just long enough.
I don’t know how one would really automate that, but I do know that ideally one wouldn’t want to.
Just having robotic eye blinks mean you may as well just have AI make the video. Not only should the eye blink both be more random, but it is also used as part of the overall acting and emotion of the character.
For example, while you may have a ‘standard blink’, if the character turns their head or even goes to look in a totally different direction, one would ‘announce’ that with a blink or part blink which may be faster or slower then standard as part of the overall action.
This of course blocks the whole iris and white of the eye’s, moves the pupil while it’s mostly hidden and then reveals it all again, allowing the viewer to be read the action. But you then don’t want some automatic blink right before or after being thrown in.
Needless to say, one doesn’t manually keyframe it all, you have a couple of blinks setup in the pose library, which allows you to quickly add all the keys, even control the amount of the motion (as in a half blink) and blend with other animation.