View and set the directory where extracted EXIF data are cached
Usage
uas_getcache(default = TRUE, quiet = FALSE)
uas_setcache(dir = "~/.R/uasimg", write = FALSE, quiet = FALSE)
uas_clearcache(quiet = FALSE)
Details
Extracting exif data from a large number of images can take awhile. To avoid having
to do this more than once for the same folder of images, the results can be saved (or cached) to
a local directory of your choice. When cache = TRUE
in uas_info
, R will
first look to see if EXIF data has already been extracted for the image folder, and if
so use it instead of running exiftool.
Cached results are saved as native R objects. Cache files store the EXIF data for a folder of
images, however if images are removed or added from a directory, any cached results will
be nullified and exiftool will run again. Cached EXIF data does not include supplemental flight metadata that you provide
with metadata text files (see uas_metadata_make
, such as the pilot's name or
location name.
uas_getcache()
retrieves the current cache directory, and uas_setcache()
sets it.
The default location is (~/.R/uasimg). When uas_setcache()
is run with
write = TRUE
, the setting will be persistent across R sessions (generally recommended).
uas_clearcache()
will delete cached EXIF data, which is sometimes called for after
a package update.