Direct method for modeling non-rigid motion with thin plate spline transformation

An apparatus for automatically estimating a thin plate spline (TPS) warp between two digital images of a sequence of digital images representing one or more physical objects, the digital images comprising pixels, the apparatus comprising:

• an input module configured to receive first and second digital images of the sequence of digital images;
• and
• a processor module configured to:
• determine a fixed template region within said first digital image,
• position a fixed set of reference points within said fixed template region,
• determine a first set of pixels within said second image, said first set of pixels corresponding to said fixed template region and including a set of projections of said fixed reference points,
• determine a TPS parameter vector from said set of projections, and
• determine a back-warped image by warping said first set of pixels based on said TPS parameter vector.

An apparatus for automatically estimating a thin plate spline (TPS) warp between two digital images of a sequence of digital images representing one or more physical objects, the digital images comprising pixels, the apparatus comprising:

• means for receiving first and second digital images of the sequence of digital images;
• means for determining a fixed template region within said first image;
• means for positioning a fixed set of reference points within said fixed template region;
• means for determining a first set of pixels within said second image, said first set of pixels corresponding to said fixed template region and including a set of projections of said fixed reference points;
• means for determining a TPS parameter vector from said set of projections;
• and
• means for determining a back-warped image by warping said first set of pixels based on said TPS parameter vector.

A computer program product, comprising a computer-readable medium having computer program instructions embodied thereon to cause a computer processor to implement a method for estimating a thin plate spline (TPS) warp between two digital images of a sequence of digital images representing one or more physical objects, the digital images comprising pixels, the method comprising:

• receiving first and second digital images of the sequence of digital images;
• determining a fixed template region within said first image;
• positioning a fixed set of reference points within said fixed template region;
• determining a first set of pixels within said second image, said first set of pixels corresponding to said fixed template region and including a set of projections of said fixed reference points;
• determining a TPS parameter vector from said set of projections;
• determining a back-warped image by warping said first set of pixels based on said TPS parameter vector.