Mocap Adventures – Part 3

In my last post i had discovered the Kinect for windows was a faulty pile of junk after going out and getting an Xbox connect which works fine.
Fastmocap: Motion capture for everyone?

Finally i started to mess about with Fastmocap and experiment with it’s capabilities. The software is as simple as it can get. It starts by initialising the Kinect sensor then right away its showing a figure on screen thats mimicking your movements. Then it’s simply a case of hitting the record button and doing your thing.

Obviously this in no way will match that of proper body strapped Sensor tech, but how well does it capture your movement?

I decided on a list of animations to try and capture.

1. Standing
2. Hold and Swing a weapon
3. Climb a ladder
4. Dance




Standing you might think would be easy and not very interesting, but there is vital small movements that make a standing pose natural looking. Unfortunately though the Kinect or Fastmocap does not really pic up minute movements in things such as wrists, shoulders and neck. In Fact to my disappointment Fastmocap does not recognise any head or neck movements at all. Unless i do a standing pose that has huge exaggerated movements there is no point in trying.

Holding a weapon, vital for making animations for sword or axe wielding heroes. Again it becomes apparent that the Kinect and Fastmocap are not really suited to detailed motion capture. The Sensor can get very confused if you bring arms close to each other but even when held apart the Fastmocap model just isn’t intelligent enough to hold a good pose. When swinging a weapon Fastmocap more than most gets confused not knowing what you are doing.

In climbing a ladder Fastmocap did a good job keeping up with me, but i in the end could not figure out how best to present climbing a ladder for the kinect in the small space that is my studio.

Where fastmocap did come up trumps was dancing. Adjusting the smoothness bar allows for the software to mirror more movement faster. This allowed for it to quite successfully record my stupid dance moves quite fluidly.

If all you want is to capture yourself dancing gingham style then i guess fastmocap is motion capture for everyone but…
They don’t tell you about the next bit.

BVH stands for ‘PAIN IN THE BUTT’

Fastmocap is easy and does what it says, records you motions and exports a file for use in other programs such as Poser, Blender etc. But really all it does is make a BVH file. Great because Second Life uploads BVH animations. Well it’s never that simple.

In most cases a file format is a file format so that they are all the same. Not the case for BVH animation files because animation files include Armatures which are bones that move and these bones can be named very different. For example a left forearm in one BVH file could be called LFarm in another and software like Second Life can only upload animations that have armature bones named a certain way.

So after the ease of fastmocap you then have to learn about how to ‘retarget’ a BVH file to be used with certain programs. A fastmocap animation exported for use with Poser does not actually work with poser. Instead you get a message saying something about getting the free upgrade once they make it compatible.

Anyway as usual there are plenty of videos and tips for Blender users about importing and fixing mobcap animations from BVH files and i managed to get the Dance animation looking correct in Blender. Unfortunately there seems to be a bug or something that is preventing the exported BVH file from blender 2.6 to be imported correctly to Second Life or Poser.

So until i can find a fix for that, I’m still unable to reach my goal of giving my brother Gemini a new mocapped Dance animation.


So verdict?

The kinect was created to map your movement on a basic level for use in video games, it’s by no means a cheap alternative for Motion capture. For the most part the results you get you could have gotten better in Poser or Daz3d and have them imported into Second Life in a mere fraction of the time.

Where mobcap speeds things up with motion sensors it takes away with its lack of exporting features making it extremely difficult to prepare and import into desired software.

The BVH animation format as widely used as it is seems severely lacking in editing support and with Blender seemingly not exporting correctly it’s left me in a bit of a dead end with this motion capture adventure.

Overall if I’m able to record, edit and import into Second life i could possibly use the Kinect/ Fastmocap for recording fast broad movements but it would be useless for detailed precise animation capture.

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