Efficient image registration

A method for efficient registration of a pair of digitized images including a first image and a second image, each image including a plurality of pixels, each pixel being associated with at least one of a gray value and a don't-care symbol, the method comprising the steps of:

• (A) selecting an initial relative displacement between said first image and said second image such that a plurality of pixels of said first image are in overlapping relationship with a plurality of pixels of said second image;
• (B) computing a registration metric value corresponding to said initial relative displacement using a Sum of Absolute Differences registration metric computation;
• (C) obtaining a registration metric value based upon said Sum of Absolute Differences registration metric computation for each of a plurality of neighboring-pixel relative displacements, and iteratively selecting a new initial relative displacement from among said plurality of neighboring-pixel relative displacements such that each succeeding new initial relative displacement is associated with a smaller registration metric value, until an initial relative displacement that is associated with a minimum registration metric value is reached.

A method for efficient registration of a pair of digitized images including a first image and a second image, each image including a plurality of pixels, each pixel being associated with at least one of a gray value and a don't-care symbol, the method comprising the steps of:

• (A) selecting an initial relative displacement between said first image and said second image such that a plurality of pixels of said first image are in overlapping relationship with a plurality of pixels of said second image;
• (B) computing a registration metric value corresponding to said initial relative displacement using a Sum of Absolute Differences registration metric computation;
• (C) locating a relative displacement that is associated with a minimum registration metric value using a two-dimensional numerical optimization analysis.

Apparatus for efficient registration of a pair of digitized images including a first image and a second image, each image including a plurality of pixels, each pixel being associated with at least one of a gray value and a don't-care symbol, the apparatus comprising:

• (A) means for selecting an initial relative displacement between said first image and said second image such that a plurality of pixels of said first image are in overlapping relationship with a plurality of pixels of said second image;
• (B) means for computing a registration metric value corresponding to said initial relative displacement using a Sum of Absolute Differences registration metric computation;
• (C) means for locating a relative displacement that is associated with a minimum registration metric value using a two-dimensional numerical optimization analysis.