Joint image compression method and apparatus

A joint image compression system comprising:

• a transform selector that selects from a plurality of transforms a selected transform that minimizes a cumulative mapping error for corresponding feature points in each of a target image and a reference image being processed by the joint image compression system, the plurality of transforms comprising a subset determined projective (SDP) transform and an affine transform;
• an image processor that forms a difference image from the target image and the reference image under the selected transform;
• and
• an image compressor that compresses the difference image to produce a compressed difference image,
• wherein the transform selector selects either the SDP transform or the affine transform depending on which one provides a smaller CME.

A method of joint compression of similar images, the method comprising:

• providing a reference image and a target image from an image capture device;
• determining parameters of a plurality of subset determined projective (SDP) transforms that minimize a cumulative mapping error (CME) of corresponding feature points in each of the reference image and the target image, an SDP transform of the plurality being identified having a smallest CME;
• determining parameters of an affine transform that minimizes the CME for the corresponding feature points;
• selecting as a selected transform either the identified SDP transform or the affine transform depending on which of the identified SDP transform and the affine transform has a smallest CME;
• and
• compressing a difference image formed by an image processor using an image compressor, the difference image being formed from a difference between the target image and the reference image under the selected transform.