image_mask: Create a mask for images in a raster data cube

Description Usage Arguments Details Note Examples

View source: R/cube.R

Description

Create an image mask based on a band and provided values to filter pixels of images read by raster_cube

Usage

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image_mask(
  band,
  min = NULL,
  max = NULL,
  values = NULL,
  bits = NULL,
  invert = FALSE
)

Arguments

band

name of the mask band

min

minimum value, values between min and max will be masked

max

maximum value, values between min and max will be masked

values

numeric vector; specific values that will be masked.

bits

for bitmasks, extract the given bits (integer vector) with a bitwise AND before filtering the mask values, bit indexes are zero-based

invert

logical; invert mask

Details

Values of the selected mask band can be based on a range (by passing min and max) or on a set of values (by passing values). By default pixels with mask values contained in the range or in the values are masked out, i.e. set to NA. Setting invert = TRUE will invert the masking behavior. Passing values will override min and max.

Note

Notice that masks are applied per image while reading images as a raster cube. They can be useful to eliminate e.g. cloudy pixels before applying the temporal aggregation to merge multiple values for the same data cube pixel.

Examples

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image_mask("SCL", values = c(3,8,9)) # Sentinel 2 L2A: mask cloud and cloud shadows
image_mask("BQA", bits=4, values=16) # Landsat 8: mask clouds
image_mask("B10", min = 8000, max=65000) 

gdalcubes documentation built on Oct. 28, 2021, 5:06 p.m.