Here’s our 40 second Fast Forward we just showed at SIGGRAPH 2012 for our paper “Fast Automatic Skinning Transformations”
Posts Tagged ‘animation’
When I overlay animations on background images there’s often a a thin outline of white or near white coming from the texture mapping + anti-aliasing in my application.
I came up with two easy ways to get around this in photoshop. First just add a black stroke to every frame. This works well for cartoons:
The other option is very similar. Add a stroke to each layer but instead of “adding” the stroke color, subtract it from the image. Select the blending options in the stroke layer style to look like this:
which produces something like:
Here’s a sneak peek at some new results.
I presented the above at SIGGRAPH ASIA in Hong Kong last week during the Technical Papers Fast Forward. Each paper gets 40 seconds to present or at least tease their work. Here’s our 40 sec video for our paper “Stretchable and Twistable Bones for Skeletal Shape Deformation” by me and my advisor Olga Sorkine.
You can do this directly with ffmpeg, but I had trouble with it and seem to remember the quality not being so good. Instead I convert my .mp4 video into an animated gif by first grabbing 10 frames every second and saving them to files using the following:
ffmpeg -i input.mp4 -r 10 output%05d.png
Then using imagemagick’s convert tool insert each frame into an animated gif:
convert output*.png output.gif
This makes a rather large .gif file for even modest videos so probably you’ll want to post process it (e.g. with Photoshop) to reduce the file size by compressing the .gif file or reducing the dimensions.
Clean up the png files using:
An animation made with our latest skinning work:
Here’s a twist applied to a bar.
But when the movie is cropped the viewer gets a sense that the bar is also being stretched, to the right.
Putting a texture (here just a the edges of the 3D model’s mesh), helps perceive the true deformation: twist.
It also helps reduce the perceived stretch effect on the original full-view movie.
Daniele Panozzo, Olga Sorkine, and I are beginning a new collaboration with Cédric Pradalier of the Autonomous Systems Lab here at ETH Zurich. We’re hosting a masters thesis project.
The project, entitled Design of a modular character animation tool is now available, and we are eagerly awaiting applications. In this thesis you will design and produce an innovative input device for interactive animation of virtual 3D characters. The device will consist of a skeleton that will imitate the structure of the character the user wants to animate. The device will be constructed of modular bones and joints which may be rearranged and repositioned on the fly. Movements of the device will be registered with the animation system and will result in corresponding movements of the virtual character. The project will present novel mechanical and electronic challenges, and will be developed in collaboration with the Interactive Geometry Lab. We will provide the required mesh processing software components. This innovative interface will improve the animation workflow used in the videogame and film industry, which by and large relies solely on keyboard and mouse interaction. A fully modular puppet, which could take the form of any character or shape, would not only present a novel interface but also provide a research instrument for evaluating human perception of 3D and 2D poses.
Please don’t hesitate to contact me for extra details.
My colleagues, Ilya Baran, Jovan Popović, Olga Sorkine, and I have just submitted the camera ready version of paper “Bounded Biharmonic Weights for Real-Time Deformation” to be presented at ACM SIGGRAPH 2011. I’ve put up a bounded biharmonic weights project page where you can find the preprint version of the article, videos and more to come.
Bounded biharmonic weights are featured in the official SIGGRAPH 2011 Technical Papers Advance Preview. The Technical Papers Chair, Hugues Hoppe, writes:
“An elegant UI framework that unifies cages, skeletons, and point constraints for 2D and 3D deformations.”
Object deformation with linear blending dominates practical use as the fastest approach for transforming raster images, vector graphics, geometric models and animated characters. Unfortunately, linear blending schemes for skeletons or cages are not always easy to use because they may require manual weight painting or modeling closed polyhedral envelopes around objects. Our goal is to make the design and control of deformations simpler by allowing the user to work freely with the most convenient combination of handle types. We develop linear blending weights that produce smooth and intuitive deformations for points, bones and cages of arbitrary topology. Our weights, called bounded biharmonic weights, minimize the Laplacian energy subject to bound constraints. Doing so spreads the influences of the controls in a shape-aware and localized manner, even for objects with complex and concave boundaries. The variational weight optimization also makes it possible to customize the weights so that they preserve the shape of specified essential object features. We demonstrate successful use of our blending weights for real-time deformation of 2D and 3D shapes.