Parametric keyframe interpolation incorporating kinetic adjustment and phrasing control

Parametric keyframing is a popular animation technique where values for parameters which control the position, orientation, size, and shape of modeled objects are determined at key times, then interpolated for smooth animation. Typically the parameter values defined by the keyframes are interpolated by spline techniques with the result that the parameter change kinetics are implicitly defined by the given keyframe times and data points. Existing interpolation systems for animation are examined and found to lack certain desirable features such as continuity of acceleration or convenient kinetic control. The requirements of interpolation for animation are analyzed in order to determine the characteristics of a satisfactory system. A new interpolation system is developed and implemented which incorporates second-derivative continuity (continuity of acceleration), local control, convenient kinetic control, and joining and phrasing of successive motions. Phrasing control includes the ability to parametrically control the degree and extent of smooth motion flow between separately defined motions.

[1]  Curtis F. Gerald Applied numerical analysis , 1970 .

[2]  Leslie Mezei,et al.  ARTA, an Interactive Animation System , 1971, IFIP Congress.

[3]  C. D. Boor,et al.  On Calculating B-splines , 1972 .

[4]  Edwin Catmull,et al.  A system for computer generated movies , 1972, ACM Annual Conference.

[5]  M. Cox The Numerical Evaluation of B-Splines , 1972 .

[6]  Marjan Spegel Programming of Mechanism Motion. , 1975 .

[7]  Nestor Burtnyk,et al.  Interactive skeleton techniques for enhancing motion dynamics in key frame animation , 1976, Commun. ACM.

[8]  Edwin E. Catmull,et al.  The problems of computer-assisted animation , 1978, SIGGRAPH.

[9]  C. R. Deboor,et al.  A practical guide to splines , 1978 .

[10]  Carl de Boor,et al.  A Practical Guide to Splines , 1978, Applied Mathematical Sciences.

[11]  I. Faux,et al.  Computational Geometry for Design and Manufacture , 1979 .

[12]  Norman I. Badler,et al.  Digital Representations of Human Movement , 1979, CSUR.

[13]  William T. Reeves,et al.  Inbetweening for computer animation utilizing moving point constraints , 1981, SIGGRAPH '81.

[14]  Parke,et al.  Parameterized Models for Facial Animation , 1982, IEEE Computer Graphics and Applications.

[15]  Craig W. Reynolds Computer animation with scripts and actors , 1982, SIGGRAPH.

[16]  Donald P. Greenberg,et al.  Path specification and path coherence , 1982, SIGGRAPH.

[17]  Local Control of Bias and Tension in Beta-splines , 1983, TOGS.

[18]  Howard Poizner,et al.  Computer graphic modeling of american sign language , 1983, SIGGRAPH.

[19]  Norman I. Badler,et al.  TEMPUS: A System for the Design and Simulation of Human Figures in a Task-Oriented Environment , 1983 .

[20]  A multiple track animator system for motion synchronization (abstract only) , 1984, COMG.

[21]  Richard H. Bartels,et al.  Interpolating splines with local tension, continuity, and bias control , 1984, SIGGRAPH.

[22]  Norman I. Badler,et al.  Design of a Human Movement Representation Incorporating Dynamics , 1985, Advances in Computer Graphics.

[23]  Tony DeRose,et al.  The Beta2-spline: A Special Case of the Beta-spline Curve and Surface Representation , 1983, IEEE Computer Graphics and Applications.

[24]  Jane Patricia Wilhelms Graphical simulation of the motion of articulated bodies such as humans and robots, with particular emphasis on the use of dynamic analysis (computer graphics, biomechanics) , 1985 .

[25]  P. Gove Webster's Third New International Dictionary , 1986 .