t

Research on refining satellite's orientation

This work presents the RPC-based bundle adjustment implemented in the free open-source photogrammetric tool MicMac. The bundle adjustment model is based on a set of polynomial correction functions. We enriched them with a physical constraint that introduces the notion of a global sensor rotation. The algorithms are evaluated against two datasets consisting of two stereo and a triplet pair of the Pleiades images. Two sets of correction functions and a number of GCPs configurations are examined. The final geo-referencing accuracy falls below the size of 1GSD.

Regardez la version anglaise

Algorithm

Hypotheses:

  1. the satellite trajectory is precise
  2. only the calibration and attitude are incorrect, therfore,
  3. the refinement can be modelled by a smooth 2D polynomial in x, and y of the image space
Figure 1. The relationship between the change in sensor attitude δαi, and the arising 2D pixel displacements Ri.

Results

Comparison with GT.

Figure 2. A results in different test scenarios. Red triangular markers correspond with the GCPs, the black circular markersare the CPs, and the vectors indicate the discrepancies between the BA-estimated and true values of control points in object space. The 0 and 1 subscripts refer to the degree of the correcting polynomial.

Publications

  • Rupnik, E., Pierrot Deseilligny, M., Delorme, A., Klinger, Y.. Refined satellite image orientation in the free open-source photogrammetric tools APERO/MICMAC. In: ISPRS Ann. Photogramm. Remote Sens. Spatial Inform. Sci., 3, pp. 83-90, 2016.
    PDF