Recovering missing pixels for Landsat ETM + SLC-off imagery using HJ-1A /1B as auxiliary data

To improve the usability of Enhanced Thematic Mapper Plus (ETM+) scan line corrector (SLC)-off data, this article proposes using HJ-1A/1B imagery as auxiliary (i.e. reference) data to recover the SLC-off ETM+ data. The least-median-of-squares (LMedS) method is newly proposed to recover missing pixels of Landsat 7 by removing the variant or abnormal digital number values. In particular, for the visible and near-infrared bands, using HJ-1A/1B for recovery has three clear advantages: the same spatial resolution, similar spectral resolution, and approximate temporal resolution. The experiments show that all of the reference-recovery methods are better than the non-reference-recovery method. The results of using of auxiliary data in reference-recovery methods, from best to worst, are Landsat 8, HJ-1A/1B, and Landsat 7. However, for recovering missing pixels, HJ-1A/1B is superior to the ETM+ auxiliary data due to the shorter time interval in Landsat 7 (a few hours). Hence, HJ-1A/1B should be considered a useful auxiliary data to recover ETM+ SLC-off imagery data.