Crow walk cycle V3 — V5

I thought it would be a good idea to refresh myself on birds before attempting the crow's walk cycle again; Jazzy shot some great footage so I spent a bit of time analysing it and trying to break down the body movements.

Looking closely at the movement of the body, you can see that birds really swing their hips when stepping. Curiously, there's not much up and down movement, it's mostly tilting from side to side — their heads actually remain almost completely level as the body moves forward, then they suddenly thrust forward to catch up as the bird lowers its leading leg.

Look at the above clip! Notice how the bird's head is almost completely stationary. 

I also found this much nicer example on Flickr that better illustrates the point:

Image courtesy of Flickr user aaardvaark

The tricky part is trying to incorporate this movement into a fairly limited 2D puppet. One of the first things I noticed is how birds tend to tilt their body forward to follow their hips — my first attempt was to simply try and replicate this movement by rotating the body of the crow. It was hilariously unsuccessful. 

Version 3

Please note I am hideously embarrassed by this.

It just ended up a confusing mess. To be fair it's more to do with the silly way that I keyframed it. There just wasn't enough room between keyframes to have the body point forwards, then back, then forwards again in time with the legs. It just looked like a weird dance. Given enough time and playing around I could probably have  but halfway through trying to fix it I just didn't feel that it was working and so gave up, rather than wasting more time on it.

I briefly considered simply sliding the wing up and down a little bit to try and give the impression of the crow's body tilting from side to side but it didn't really work too well.

For the next attempt I tried to emulate the way that a bird's body sort of shifts forward and backward rather than giving it a lot of up and down movement. I also gave the wing a very tiny amount of rotation to try and give the impression that the body was going more side-to-side than up and down.

Version 4

Disregard the disconnected head for a moment if you will — I was trying something out and unparented the neck from the body. If this motion had been more successful I would have connected it.

This version's looking better but I still was't totally satisfied with it. It certainly could have worked and would have been acceptable, but I just found that it just wasn't "birdlike" enough. It's a bit rhythmic and robotic looking. I also found that the sliding of the body back and forth was a bit distracting — she's walking on the spot, so it didn't really make sense to have it shift back and forth like that.

Version 5

Again, a disconnected head. Taking into account what Sam suggested about an up-and-down body movement I tried replacing the forward and backward motion with an up and down one. I think it looks a lot better — less distracting to look at and it flows quite nicely. I still wasn't entirely pleased, though — the head bob seems a little too exaggerated and I'm not too sure about the legs. Something seems a bit off to me; they animate fairly well, give or take a few glitches, but again, they just don't seem "birdish" enough to me.

I found another interesting reference video; somebody animated a rather lovely walk cycle with an interesting bird rig:

Check out the lovely movement on this one! You can really clearly see the side-to-side motion and how the bird crosses its legs in front of one another. The neck and leg movement are particularly interesting. Obviously it's not a crow, so her head wouldn't move in quite the same way, but the way they've pulled off the head bobbing with an on-the-spot walk cycle is very interesting. Up until now I'd only been pushing it back and forward — it didn't occur to me to try tucking it down and pushing it up as she moved!

It also helped me to identify what seemed to be bothering me about the legs. Notice how the bird doesn't push itself onto its toes at all — the leg is lifted straight off the ground in a wide arc. I think that's the issue with my own cycle — her foot moves in a very human manner. It looks alright and I think I could get away with it but I might like to try tweaking it so that it lifts without the foot rolling.

Crow flight cycle reference and planning

Following on from Jazzy's bold attempts to stalk crows with a camera and capture them landing, I've been looking at how we might be able to animate the scene where the crow swoops in and lands on the scarecrow's arm as painlessly as possible.

By an astonishing coincidence I found this rather interesting video on Youtube:

I find the whole situation hilariously ironic - it's almost exactly the sort of movement we want and it's done in After Effects with an almost puppety looking bird. Of course, owing to the simplicity of the shape the animator was able to get a good deal more flexibility in his bird - note the flexing and arching of the back - it would be significantly more difficult to achieve with our puppet. I would imagine that he used a vector shape or mask of some sort within After Effects and was able to bend and flex the shapes at will. It's an interesting technique and certainly not one I would have considered. I could be totally wrong, of course - he may have done something totally different. I may actually ask him how he did it, mostly out of curiousity, but it may also be beneficial to us and give us some kind of insight as to how we can better approach this scene.

Regardless, it's a useful video to clearly examine the motion of the bird's landing.

From some quick doodles scribbled in Liz's lecture today (don't worry, I was paying attention!) I started looking at how the body would rotate as the crow comes into land, wondering if we might be able to simply use the same body and rotate it, or whether it would be necessary to draw new ones. Happily it seems we'll be able to re-use it. She'd lift her feet and spread her wings wide as she comes in, flapping to keep balance. We could probably use the same wings as well - they wouldn't necessarily change shape or perspective, simply rotate them along with the body.

I think we'd probably need about three "frames" for the wings - an 'up' pose, a 'down' pose and a 'mid' pose. As with the previous bird tests I did, we could probably rotate the wings down on the Z axis and then switch them to the 'mid' position once they get far enough. Hold that for a few frames, then they come down. They'd be blurred, too, I imagine - so that should cover up any choppy 'cuts' between each position!

If the wings are divided up into two or three sections, say, we could even try to get a bit of overlap by delaying the ends of the wings as she flaps up and down.

Puppet pose planning and reference

Starting to develop more puppets and thinking about how best to articulate each one. It's much trickier than you'd think; despite the crow's relatively simple design there are a lot of body parts to consider. I've been trying to think economically in terms of re-using as many pieces as possible whilst still maintaining lively and expressive poses and overall quality of animation.

I started with a fairly simple pose from a scene that doesn't require a great deal of movement in the crow — right at the end, when she's perched on the scarecrow, holding the bug in her beak. If done correctly, this pose could potentially be re-used for the scene where she actually lunges forward and grabs the bug from his hat as well. 

It looks totally awful at the moment — it's those blinking wings. I have a basic understanding of their overall structure and mechanics, but trying to rotate them and picture the folding from such a weird angle is incredibly difficult. The one at the top would probably work but I just really wasn't happy with it. The angle isn't quite right, really — the scene in question is more of an over-the-shoulder shot, whereas that one's a little more side-on. It could be used for the bug-grabbing scene, however! 

On the top left is the sketch from the 'above' puppet I posted previously. Nothing to say there.

It was pretty hopeless trying to completely imagine how the wings might fold so I compiled a bunch of beautiful reference images pilfered from Flickr! I opted to grab pictures of regular birds as well as crows — partially because there weren't many images of crows from the angle I wanted. The one on the far-right of the middle row is probably the most useful for my purposes, so it's the one I focused on most.

From the references I was able to scribble something that made a bit more sense — it took me a few tries and it's still far from perfect. I was using a poor-quality printout, however, and it was pretty difficult to see too much detail to reference. I started having real trouble with the head at this point — I tried hiding more of the beak behind the head to better suggest the angle but it just looked a bit peculiar. I think I finally sort-of got it though?

I'm not going to worry too much about the detail of the sketch at this point. It's really just to provide a base to work from — it will be much easier to correct all the horrible mistakes digitally.

I also started thinking a bit more about the wings and flight cycle at this point and how we might go about animating that with nothing but puppets as painlessly as possible.

As before, I started digitally sketching the base of the puppet in Photoshop. The reference on-screen was much clearer and easier to see so it was much easier to get the angle of the wings correct.

I also replaced the original head with one of the others that I had drawn, which fit the angle of the body much better. 

Once the sketch was complete I started going over it again with the pen tool, creating blocky shapes on each layer for each relevant body part. In retrospect it probably wasn't necessary as the crow isn't going to really move at all, but I figure it's always a good move to have articulated puppets ready just in case.

I had a bit of an issue with the outlines - the normal method of simply "stroking" each section wasn't really going to work in this instance - the way I'd divided up the limbs looked a bit weird when stroked like that. The shapes were a bit clunky and awkward. I would have had to alter a lot of the outlines by hand to make it work, so I opted to just draw them myself. It allowed me to keep a lot of the original detail - I think (hope?!) it looks a bit better this way:

Thinking a little further about the more complex sections of the animation, I started trying to figure out how we might look at doing the crow's run for the hang glider chase scene. In theory, it shouldn't be causing too much problem, as it's mostly actually already animated within the animatic. The difficulty, for me, is knowing how far to take it and how to make it fit within the puppet design. 

The animatic version is a simple two-frame cycle of the crow's legs simply going up and down. There's a bit of keyframing to move her up and down and side to side as she runs. Something like this could probably work reasonably well within the final animation, however I wasn't sure whether or not I should look to making the cycle a little more polished and actually animate the legs properly. One thing I'd considered doing was to have maybe three frames for the feet - one flat on the ground, the other being lifted up, and the other outstretched in front. I thought we could maybe take a simple leg shape and rotate it in 3D space along the Z axis to appear as if it was rotating upwards, lying flat towards the camera, to give the impression that she was lifting her leg. As the leg rotated the "lifted" foot could be used, switching to the "outstretched" foot when her leg is fully extended.

I'd really need to put an example together - it's a bit tricky to explain...!

I've started loosely sketching out a potential puppet, trying to figure out how to not make it look utterly ridiculous. Front angles are tricky at any rate, let alone for bloody birds... No matter what I do her face always looks stupid

I was referring heavily to the crow Jazzy drew for the animatic - it's pretty perfect, I've just got to try and adapt it into the style of the crow puppet.

I really don't know about the beak or anything about the face. I think the top of the beak... the bridge-y nostril bit possibly needs to be wider? The expression looks off. She doesn't look particularly scared. It just doesn't have the charm or humour or simplicity of the original, I just don't know how to make it work. I'm not sure if my leg idea will work either - still, best to try eh?

The last thing I started looking at were wings! Specifically, their application to the scene where the crow leaps into the air and runs from the hang glider. The animatic shows her leaping in shock, looking behind her before turning and bolting. This sounds like it would require a great deal of additional puppets, but I've been thinking about it a bit and I reckon it might be possible to get away with just one, using a couple of additional heads and wings for the jump. The body and legs could be recycled from the side-on run (which is going to be very similar to the walking puppet). We could probably just lift her legs and feet (as shown in the terrible doodles at the top there) and attach a new head and set of wings.

We could potentially animate her wings very similarly to how I did the flying crows - we could use one or two basic wing shapes and simply keyframe them up and down at high speed, then apply a heavy motion blur so all you get is a blurred shape flailing about. Maybe we could even kick her legs and shake her tail a bit!

The question of how to fold her wings back up for when she starts running is a bit trickier. We could probably get away with just adding a blurred mid-pose as she draws them back to her body - the whole movement will be very quick so I think we can get away with being pretty loose with it.

I'll have to do some tests to see whether it will work or not. Hopefully it will!

Crow Footage

These are three out of... five films I recorded of crows. A couple of them are good, the others are terrible XP I didn't manage to put them all up here because vimeo has limits to how many you can do a day... which I'm sure you guys already knew :)

I was hoping they could help you Alex understand a crow walk better. I know there are some videos on youtube etc. with them but sometimes good ones are hard to find. You already said to me when I showed you them that they'll be helpful so that's good news. However, I'm still on the hunt for a good landing film, aka. when they land on a street light.

Unfortunately I've seen them, I just didn't manage a decent filming. But by observing them I have an idea of how they do it. They tend to fly lower than the top point of the streetlight before lifting their legs up and allowing their flight speed and the wind to lift them up to the top. They then regain control by quickly flapping a few times before landing. I might make a sequence of sketches from what I have seen and I'll continue to get the landing on camera.

Watch out for the Bird Watcher with the hat crows! 8]