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Create a lazy table reference from a GeoTIFF raster

Source: R/tbl.R
tbl_tiff.Rd

Opens a GeoTIFF file and returns a lazy query node. Each pixel becomes a row with columns x, y, band1, band2, etc. Coordinates are pixel centers derived from the affine geotransform. NoData values become NA.

Usage

tbl_tiff(path, batch_size = .TIFF_BATCH_SIZE)

Arguments

path

Path to a GeoTIFF file.

batch_size

Number of raster rows per batch (default 256).

Value

A vectra_node object representing a lazy scan of the raster.

Details

Strip and tiled files are read, uncompressed or compressed with DEFLATE or LZW, with the horizontal-differencing (2) and floating-point (3) predictors undone on read.

Use filter(x >= ..., y <= ...) for extent-based cropping and filter(band1 > ...) for value-based cropping. Results can be converted back to a raster with terra::rast(df, type = "xyz").

Examples

# \donttest{
f <- tempfile(fileext = ".tif")
df <- data.frame(x = as.double(rep(1:4, 3)),
                 y = as.double(rep(1:3, each = 4)),
                 band1 = as.double(1:12))
write_tiff(df, f)
node <- tbl_tiff(f)
node |> filter(band1 > 6) |> collect()
unlink(f)
# }