Effect of the DTM quality on the bundle block adjustment and orthorectification process without GCP: Exemple on a steep area

This paper presents the registration and orthorectification, without any GCP, of multi-date satellite data acquired in the Himalayas. To solve that problem, a complete and automatic pipeline that performes tie points detection through a Fourier transform based correlation, bundle block adjustment and orthorectification has been developed. The paper focuses on the effect of the DTM in the bundle block adjustment and the orthorectification step by comparing a SRTM DTM and a Pleiades DTM in the developed pipeline. The results show that the matching technique allows the detection of a well distributed number of tie points whereas the use of a precise DTM lead to a better result in the bundle block adjustment. Finally, the use of precise DTM for data orthorectification leads to finely registered images.