Orthorectification For Multi Detector High Resolution Sensors

Typical high resolution sensors employed for large swath coverage consists of multiple detectors in focal plane. Aligning these detectors in Image plane is more challenging if camera is steerable. The usability of standard geo-corrected data products becomes challenging for any kind of space application if systematic correction accuracies are in the order of kilometers. Ortho rectification becomes mandatory and more complex to achieve pixel level accuracy from stitched image formed by the images from individual detectors. In this case, each image produced by individual detector needs to be ortho-rectified separately before a final mosaic. A method based on multi scale image matching has been developed to produce an ortho-rectified high resolution large swath product. The methodology developed is validated against many IRS-IC/ID temporal PAN sensor data sets, which made up of 3 individual detectors PANI, PAN2, and PAN3, each with 23.7 km swath with 5. 8m ground sampling distance. The geo-location error of the products generated is at sub-pixel level accuracy with respect to the reference.