Read catalog from JSON file — read

Load an image catalog previously saved with write_catalog().

Usage

read_catalog(file)

Arguments

file: Path to catalog JSON file.

Value

An image_catalog object.

Examples

# Build a tiny study tree with empty placeholder files
root <- tempfile("study_")
for (s in c("01", "02")) {
  d <- file.path(root, paste0("sub-", s))
  dir.create(d, recursive = TRUE)
  invisible(file.create(file.path(d, c("cope1.nii.gz", "varcope1.nii.gz"))))
}
catalog <- image_catalog(root, "sub-*/*.nii.gz",
                         path_regex = "sub-(?<subject>[^/]+)")

manifest <- tempfile(fileext = ".json")
write_catalog(catalog, manifest)

catalog2 <- read_catalog(manifest)
catalog2
#> Image Catalog
#>   Files: 4
#>   Root: /tmp/Rtmp17Odxi/study_1cec74c9afa5
#>   Pattern: sub-*/*.nii.gz
#>   Metadata columns: subject
#>   Subjects: 2 (01, 02)

unlink(c(manifest, root), recursive = TRUE)