A variety of image files with embedded EXIF metadata. Each folder is titled with the camera model.
ExifTool is terrific for command-line extraction of data, manipulation / geotagging, and renaming of files.
To produce the exifdata csv file I used:
exiftool -n -common -GPSLongitude -GPSLatitude -GPSAltitude -csv -r . > exifdata.csv
Copy from an SD card (Nikon folder example) to another, renaming by datetime and geotagging from GPX. This takes no longer than copying the files from the SD card in the first place - and eliminates the long copy time when geotagging later (which by necessity rewrites the entire file).
exiftool -r /Volumes/NIKON\ D5600/DCIM/ \ # Source directory
-d %Y%m%d%H%M%S%%-c.%%le \ # Read capture datetime and produce YYYYMMDDHHMMSS format
'-filename<FOLDER/PREFIX_${DateTimeOriginal}' \ # Rename with folder destination and prefix
-geotag GPXFILE.gpx # the source GPX file