macOS script to use exiftool to extract depth from iPhone JPG, HEIC images

extract_depth.sh

#!/bin/bash

PATH=$PATH:/usr/local/bin
checkdep(){
    command -v $1 && return
    msg="Please install Homebrew by visiting https://brew.sh."
    [[ "$1" == "brew" ]] || msg="Please install ${1} with 'brew install ${1}'."
    osascript -e "tell app \"System Events\" to display dialog \"$msg\""
    exit 0
}
checkdep brew
checkdep exiftool
checkdep heif-convert
mkdir -p /tmp/extracted

trympimg(){
  outfile="/tmp/extracted/$(basename "$1")-MPImage${2}.jpg"
  exiftool "$1" -b -MPImage"${2}" > "$outfile"
  [[ -s "$outfile" ]] || {
    rm "$outfile"
    [[ "$2" -gt "2" ]] && {
        return 0
    }
    return 1
  } && trympimg "$1" $(($2+1))
}

tryheic(){
  outfile="/tmp/extracted/$(basename "$1").jpg"
  heif-convert -q 100 "$1" "$outfile"
}

tried=0
success=0
for f in "$@"
do
  tried=$((tried+1))
  trympimg "$f" 2 && cp "$f" /tmp/extracted || tryheic "$f" && success=$((success+1))
done

msg="Done. Tried ${tried} files, ${success} of them were successful."
osascript -e "tell app \"System Events\" to display dialog \"$msg\""
[[ "$success" -gt 0 ]] && open /tmp/extracted

Here it is packaged as a .app file. (Drag and drop images to use)
Still requires exiftool and libheif to be installed through Homebrew.
https://www.dropbox.com/s/vv2xnnap32a7qvq/exiftool_extract.zip?dl=0