Optimize PNG images using pngcrush

optimize.sh

#!/bin/bash

original_total=0
final_total=0
saved_total=0

# Calculate original total size
while IFS= read -r -d '' file; do
    size=$(stat -c "%s" "$file")
    original_total=$((original_total + size))
done < <(find . -name "*.png" -type f -print0)


# Perform parallel compression and recalculate sizes
find . -name "*.png" -type f -print0 | parallel -0 -j+0 '
    original_size=$(stat -c "%s" "{}")
    pngcrush -brute -blacken -ow "{}"
    compressed_size=$(stat -c "%s" "{}")
    saved=$((original_size - compressed_size))

    echo "File: {}, Original Size: ${original_size} bytes, New Size: ${compressed_size} bytes, Saved: ${saved} bytes"
'

# Calculate final total size
while IFS= read -r -d '' file; do
    size=$(stat -c "%s" "$file")
    final_total=$((final_total + size))
done < <(find . -name "*.png" -type f -print0)

saved_total=$((original_total - final_total))

# Format total sizes into human-readable format
formatted_original_total=$(numfmt --to=iec --suffix=B "$original_total")
formatted_final_total=$(numfmt --to=iec --suffix=B "$final_total")
formatted_saved_total=$(numfmt --to=iec --suffix=B "$saved_total")

if [[ $final_total -lt 0 ]]; then
    formatted_final_total="-${formatted_final_total#-}"
fi
if [[ $saved_total -lt 0 ]]; then
    formatted_saved_total="-${formatted_saved_total#-}"
fi

# Log total sizes and storage saved
echo "Original Total Size: $formatted_original_total"
echo "Final Total Size: $formatted_final_total"
echo "Total Storage Saved: $formatted_saved_total"