#!/bin/bash
#
# images_resize Resizing large JPGs in current directory
# Based on: https://shkspr.mobi/blog/2016/12/converting-rar-to-zip-in-linux/
#
# Usage: xxx.sh

echo "Resizing large JPGs in $(pwd)"

MAX_PIXELS=8000000
MAGICK_COMMENT="magick:resize=8mp,quality=85,sampling=4:2:0"

find . -regextype posix-egrep -regex ".*\.(jpg|JPG|JPEG|jpeg)$" -print0 | while IFS= read -r -d '' f
do
    # Skip files already processed with these parameters
    COMMENT=$(~/Applications/magick identify -format "%c" "$f" 2>/dev/null)
    if [[ "$COMMENT" == "$MAGICK_COMMENT" ]]; then
        echo "Skipping $f: already processed"
        continue
    fi

    # Get file size before resizing
    SIZE_BEFORE=$(stat -f%z "$f" 2>/dev/null || stat -c%s "$f" 2>/dev/null)

    ~/Applications/magick "$f" -resize "${MAX_PIXELS}@@\>" -sampling-factor 4:2:0 -strip -quality 85% -set comment "$MAGICK_COMMENT" "$f"

    # Get file size after resizing
    SIZE_AFTER=$(stat -f%z "$f" 2>/dev/null || stat -c%s "$f" 2>/dev/null)

    # Display before/after sizes
    echo "Resized $f: $(numfmt --to=iec-i --suffix=B $SIZE_BEFORE) -> $(numfmt --to=iec-i --suffix=B $SIZE_AFTER)"
done