duplicate-exif

#!/bin/bash

# Given a gif file, look for a matching webp file,
# and if found, duplicate its metadata into the gif.

# Utility to synchronise information from one version of an image to another.
# Used to propogate information that was attached to a webp to its derivative gif
#  Because I downloaded a bunch, then converted them,
# but actually should have saved some of their info from the original.
# Specifically original GUID and provenance

# Parse command-line arguments using getopts
force=0
while getopts ":f" opt; do
  case $opt in
    f)
      force=1
      ;;
    \?)
      echo "Invalid option: -$OPTARG" >&2
      exit 1
      ;;
  esac
done
shift $((OPTIND-1))

# Check if the source file exists
if [ ! -f "$1" ]; then
  echo "Source file not found: $1" >&2
  exit 1
fi

# Generate the target file name
source_file="$1"
target_file="${source_file%.*}.webp"

# Check if the target file exists
if [ ! -f "$target_file" ]; then
  if [ "$force" -eq 1 ]; then
    # Generate a new WebP file from the source GIF using mogrify
    mogrify -format webp "$source_file"
    target_file="${source_file%.*}.webp"
    echo "Creating: $target_file" >&2
  else
    echo "Target file not found: $target_file" >&2
    echo "Invoke this script with the --force (-f) option to auto-convert and create it" >&2
    exit 1
  fi
fi

# Copy EXIF metadata from the source file to the target file using exiftool
exiftool -tagsFromFile "$source_file" "-all:all>all:all" -overwrite_original "$target_file"
echo "Updated EXIF metadata on $target_file" >&2