Prepare 360 photo for Facebook with max resolution

360-photo-facebook.sh

#!/bin/sh

# Max settings, working Jan 2025
MAX_WIDTH=16384
MAX_FILESIZE_KB=16000

# Display help if --help or no arguments are provided
if [ "$#" -eq 0 ] || [ "$1" = "--help" ]; then
    echo "Usage: $0 equirectangular_360_image.jpg"
    echo ""
    echo "Resizes the input equirectangular image to the maximum resolution"
    echo "and file size allowed by Facebook, adds 360 metadata, and saves a copy."
    echo ""
    echo "Options:"
    echo "  --help       Displays this help message."
    echo ""
    echo "Example:"
    echo "  $0 my_360_photo.jpg"
    exit 0
fi

FILE=$1
FILENAME="${FILE%%.*}"
EXT="${FILE##*.}"
NEW_FILE="${FILENAME}_fb.$EXT"

echo "Resizing uniformly to max width $MAX_WIDTH pixels..."
magick "$FILE" -resize "${MAX_WIDTH}x" "$NEW_FILE"
echo "Reducing max file size to ${MAX_FILESIZE_KB}kb..."
magick "$NEW_FILE" -strip -define jpeg:extent="${MAX_FILESIZE_KB}kb" "$NEW_FILE"
echo "Adding equirectangular metadata..."
exiftool -overwrite_original -quiet -all= -ProjectionType="equirectangular" "$NEW_FILE"

echo "\nSaved $NEW_FILE with 360 metadata and max resolution/file size for Facebook."