Detecting land-cover modifications from multi-resolution satellite image time series

Frequent high-resolution images will be provided by new satellites such as Venμs, SENTINEL-2 and Landsat Data Continuity Mission. Methods to handle this new type of data are currently developed (see [1] for an example). However, a more frequent observation of the surface of the Earth may be required for some applications. Moreover, the temporal resolution may be reduced by meteorological artifacts. In this work, we propose to take advantage of the higher temporal resolution of satellites with a lower spatial resolution to detect land-cover modification at a high spatial resolution. The proposed approach does not use any fusion step of the high- and low-resolution images. We show that the low spatial resolution satellite image time series (SITS) can be used in order to inform about the stability and relevance of the high spatial resolution classification. Experiments include a wide variety of resolution ratios and study the use of each ratio for the assessment of high resolution classification maps (computed from the high spatial resolution SITS).