Exterior Orientation of CBERS-4/PAN Imagery Using Rigorous Models

Abstract

The process of geometric correction in orbital images is an indispensable step, that makes feasible the generation of reliable cartographic products, which can be used in many applications. The imagery satellites have embedded sensors integrated with other devices that jointly provide orbital images, which present different levels of details and positional accuracy. Thus, it is important to analyze the quality of the orbital images of the CBERS-4/PAN, which presents a GSD (Ground Sample Distance) of 5 m as well as the procedures that can be adopted to improve them. CBERS-4 is considered a recent satellite and there are few studies on its positional reliability and geometric correction of generated products, mainly of PAN (Panchromatic and Multispectral Camera) images. In this work, the exterior orientation of the CBERS-4/PAN images was performed with the rigorous mathematical model based on the collinearity equations adapted for the pushbroom sensor model. Orbital data were used as a relative constraints and the number of control points were varied – 15, 10 and 5, which coordinates were obtained from the land parcel boundaries registered in INCRA (National Institute of Colonization and Agrarian Reform). Geometrically corrected images with more reliable positional accuracy (10 to 15 m) were generated.