BACKGROUND

The use of satellite-based and aerial-based imagery is popular among government and commercial entities. To such entities, it can be useful to piece together thousands of separate images (referred to herein as input images) taken from satellites (or other remote sensors) into an orthorectified mosaic. For purposes of this document, a mosaic is a composite image created by arranging together a plurality of smaller images (the input images). For purposes of this document, orthorectification is the process of removing the effects of image perspective (tilt) and relief (terrain) for the purpose of creating a planimetrically correct image. The resultant orthorectified images often have a constant scale wherein features are represented in their “true” positions. This allows for the accurate direct measurement of distances, angles, and areas. Orthorectified images are commonly used as in visualization tools such as, for example, Google Earth.

Because it is not a routine matter to align and orient separate images relative to each other to produce an orthorectified mosaic, misalignment errors are common. While co-alignment can be performed, the process is rarely perfect. Misalignment errors can result in a straight road or edge of a building appearing in the orthorectified mosaic as a road or building edge with a inflection point at the seam between images or in which the road segments in the two different images on either side of the seam do not intersect (see e.g., misaligned roads, parking lots, and buildings in the example orthorectified mosaic ofFIG.1). If the resulting orthorectified mosaic is not of suitable quality (e.g., due to misalignment), the set of input images can be adjusted (e.g., add or remove input images from the set of input images) and the processes of orthorectifying and creating the mosaic can be repeated. However, the processes of orthorectifying and creating the mosaic use a large amount of computational resources and take a lot of time. Therefore, performing numerous iterations of orthorectifying and creating the mosaic is expensive and sometimes not practical.

