Anamorphic Desqueeze DNG Script

Anamorphic_DeSqueeze_Tool.sh

#!/bin/bash
# Change to the directory where the script is located
cd "$(dirname "$0")"

# Clear the terminal screen
clear

# Tool Intro Text 
echo -e "\033[1mAnamorphic DNG EXIF DeSqueeze for Exiftool - written by Rupert Warries for MAC OS\033[0m\n\n\033[1m------------ \033[0m\n\nThis Tool will rewrite each DNG's EXIF data to allow Lightroom to render each image de-squeezed in DEVELOP module (library will still show squeezed image - any program that reads the pixel ratio in EXIF will also work)."
echo -e "\n\nUSAGE INSTRUCTION :\n1. Place this script from inside the folder containing the DNG images for processing\n2. Drag tool into a terminal window to run and follow the prompts\n3. DNG filenames must contain no spaces - run the tool by dragging into a terminal window and following the prompts\n4. an installation of Exiftool must be present for this script to operate\n\n\033[1m------------ \033[0m"

# Show the directory and ask for confirmation
echo -e "\nAll DNG files present will be de-squeezed in the following directory:\n$(pwd)\n"
read -p "Do you want to continue? (Y/N): " confirm

# Check user input
if [[ $confirm != [Yy] ]]; then
  echo "Processing cancelled."
  exit 1
fi

# Ask for squeeze factor and loop until a valid positive number is entered.
# Values greater than 1.0 stretch horizontally. Values less than 1.0 stretch vertically.
while true; do
  read -p "Enter the lens squeeze factor (e.g. 0.75, 1.0, 1.33, 1.5, 2.0): " squeeze_factor

  # Check if the input is a valid positive number, including values like .75
  if [[ $squeeze_factor =~ ^([0-9]+([.][0-9]*)?|[.][0-9]+)$ ]] && awk "BEGIN { exit !($squeeze_factor > 0) }"; then
    break
  else
    echo "Desqueeze must be a positive number"
  fi
done

# DefaultScale is stored as two values: horizontal scale first, vertical scale second.
# Keep the unstretched dimension at 1.0. For values below 1.0, invert the input so
# the image is stretched vertically instead of squeezed horizontally.
if awk "BEGIN { exit !($squeeze_factor >= 1) }"; then
  default_scale_h=$(awk -v v="$squeeze_factor" 'BEGIN { printf "%.2f", v }')
  default_scale_v="1.0"
else
  default_scale_h="1.0"
  default_scale_v=$(awk -v v="$squeeze_factor" 'BEGIN { printf "%.2f", 1 / v }')
fi

# Process files in the current directory
while IFS= read -r -d '' file; do
  exiftool -DefaultScale="$default_scale_h $default_scale_v" -overwrite_original "$file"
done < <(find . -maxdepth 1 -type f \( -iname "*.DNG" -o -iname "*.dng" \) -print0)

# Print confirmation message
echo -e "
Processing complete
DNG's EXIF rewritten with a $default_scale_h $default_scale_v DefaultScale from a $squeeze_factor squeeze factor
"