pdfimages

pdfimages -j foo.pdf  bar

This will extract all images from foo.pdf and save them in JPEG format (option -j) to bar-000.jpg, bar-001.jpg, bar-002.jpg, etc.

delete metadata

exiftool -exif:all= *.jpg
exiftool -xmp:all= *.jpg

or use MAT: Metadata Anonymisation Toolkit https://0xacab.org/jvoisin/mat2