Daily and monthly MODIS snow cover L3 data has downloaded, next to deal with missing and negative cells. Different types of interpolation are being used to fill the missing cells. I want to fill the missing cells with mean of 3 surrounding values but it is very hard because in some cases large portion of data is missing? I know to mask the NaN cell by using (nanmean) command and long term mean of same area can also be use.
Permafrost Presence/Absence Mapping of the Qinghai-Tibet Plateau Based on Multi-Source Remote Sensing Data but I am looking any possible way beside these.
What is the best way beside above mentioned two to deal the missing and negative cells of MODIS snow cover data?
Note; I am using matlab environment for this purpose.