remove fill value

R/blackmarbler.R

@@ -58,6 +58,46 @@ pad3 <- function(x){
 }
 pad3 <- Vectorize(pad3)
 
+remove_fill_value <- function(x, variable){
+  # Apply scaling factor to variables according to Black Marble user guide
+
+  # https://viirsland.gsfc.nasa.gov/PDF/BlackMarbleUserGuide_v1.2_20220916.pdf
+  # * Table 3 (page 12)
+  # * Table 6 (page 16)
+  # * Table 9 (page 18)
+
+  if(variable %in% c(
+
+    # VNP46A1
+    "DNB_At_Sensor_Radiance",
+
+    # VNP46A2
+    "DNB_BRDF-Corrected_NTL",
+    "Gap_Filled_DNB_BRDF-Corrected_NTL",
+    "DNB_Lunar_Irradiance",
+
+    # VNP46A3/4
+    "AllAngle_Composite_Snow_Covered",
+    "AllAngle_Composite_Snow_Covered_Std",
+    "AllAngle_Composite_Snow_Free",
+    "AllAngle_Composite_Snow_Free_Std",
+    "NearNadir_Composite_Snow_Covered",
+    "NearNadir_Composite_Snow_Covered_Std",
+    "NearNadir_Composite_Snow_Free",
+    "NearNadir_Composite_Snow_Free_Std",
+    "OffNadir_Composite_Snow_Covered",
+    "OffNadir_Composite_Snow_Covered_Std",
+    "OffNadir_Composite_Snow_Free",
+    "OffNadir_Composite_Snow_Free_Std")
+  ){
+
+    if(x == 65535) x <- NA
+
+  }
+
+  return(x)
+}
+
 apply_scaling_factor <- function(x, variable){
   # Apply scaling factor to variables according to Black Marble user guide
 
@@ -73,7 +113,7 @@ apply_scaling_factor <- function(x, variable){
 
     # VNP46A2
     "DNB_BRDF-Corrected_NTL",
-    "Gap_Filled_DNB_BRDFCorrected_NTL",
+    "Gap_Filled_DNB_BRDF-Corrected_NTL",
     "DNB_Lunar_Irradiance",
 
     # VNP46A3/4
@@ -90,7 +130,9 @@ apply_scaling_factor <- function(x, variable){
     "OffNadir_Composite_Snow_Free",
     "OffNadir_Composite_Snow_Free_Std")
   ){
+
     x <- x * 0.1
+
   }
 
   return(x)
@@ -224,6 +266,9 @@ file_to_raster <- function(f,
   #assign the extents to the raster
   extent(outr) <- rasExt
 
+  #set fill values to NA
+  outr <- remove_fill_value(outr, variable)
+
   #apply scaling factor
   outr <- apply_scaling_factor(outr, variable)