In recent years, considerable developments have occurred in the field of digital photogrammetry. These have been due mainly to increases in computing power, the refinement of feature and area-based image matching algorithms and the reduction in the cost of equipment capable of producing near real-time images in digital format. A major limitation to the widespread application of digital photogrammetry concerns the small format size of the CCD sensor itself and, consequently, the number of pixels on the sensor being limited in number. Much time and effort has been expended trying to improve coverage through hardware solutions such as producing imaging sensors with increased numbers of pixels. An alternative software solution is offered in this paper. An algorithm which combines several digital images, the photogrammetric technique of area-based image matching, and a rigorous mathematical solution to increase the effective number of pixels is described. The resolution of the final composite image is enhanced relative to its constituent images.
Photogrammetric Engineering & Remote Sensing Vol. 67, p. 741-749