Orientation and self-calibration of ALOS PRISM imagery


KOCAMAN S. , Gruen A.

PHOTOGRAMMETRIC RECORD, cilt.23, ss.323-340, 2008 (SCI İndekslerine Giren Dergi)

  • Cilt numarası: 23 Konu: 123
  • Basım Tarihi: 2008
  • Doi Numarası: 10.1111/j.1477-9730.2008.00493.x
  • Dergi Adı: PHOTOGRAMMETRIC RECORD
  • Sayfa Sayısı: ss.323-340

Özet

High-resolution satellite images (HRSI) at sub-5 m footprint are becoming increasingly available. A set of algorithms for processing of HRSI has been developed at the Institute of Geodesy and Photogrammetry (IGP), ETH Zurich and realised in a software suite called Satellite Image Precision Processing (SAT-PP). The software has been used for the processing of a number of high resolution satellite sensors, such as IKONOS, QuickBird, SPOT 5 HRS/HRG, Cartosat-1 and ALOS PRISM. PRISM is a panchromatic radiometer carried on board the Japanese ALOS satellite. It has three optical systems for forward, nadir and backward view with 2.5 m ground sample distance (GSD). The photogrammetric processing of PRISM imagery has special requirements owing to the linear array CCD sensor structure and special characteristics of the interior geometry and exterior orientation. As a member of the ALOS calibration/validation team, new algorithms for geometric processing of the PRISM images have been implemented at the IGP, in particular for the interior orientation and self-calibration. The physical sensor model in SAT-PP is refined according to the multiple camera heads of the sensor. The rigorous model for PRISM is based on a modified bundle adjustment with the possibility of using two different trajectory models. The self-calibration is introduced into the adjustment to model the systematic errors of the sensor and the system as a whole. The methods of georeferencing and digital surface model (DSM) generation were tested using the PRISM data-sets acquired over five different testfields. The rigorous sensor model performed well and resulted in sub-pixel accuracy for point positioning in all testfields. The self-calibration model has been tested in two different phases of the project separately. In the initial phase, where interior orientation data was not available, the use of the self-calibration was essential to achieve good accuracy. However, in the later phase the relative positions of the CCD chip detectors on the focal plane were provided by the Japan Aerospace Exploration Agency (JAXA) and the improvements by self-calibration became less significant. A detailed analysis of the DSM generation is presented in another publication.