How to Decrypt a PDF File on Mac: Remove Password from PDF Files on macOS

decrypt_pdfs.sh

#!/bin/bash

#https://becomegeeks.com/blog/how-to-decrypt-a-pdf-file-on-mac-remove-password-from-pdf-files-on-macos/

PASSWORD=""
INPUT_DIR=""
OUTPUT_DIR=""

while [[ "$#" -gt 0 ]]; do
    case "$1" in
        -password=*) PASSWORD="${1#*=}"; shift ;;
        -inputDir=*) INPUT_DIR="${1#*=}"; shift ;;
        -outputDir=*) OUTPUT_DIR="${1#*=}"; shift ;;
        *)
            echo "Unknown option: $1"
            echo "Usage: $0 -password=<password> -inputDir=<input_directory> -outputDir=<output_directory>"
            exit 1
            ;;
    esac
done

if [[ -z "$PASSWORD" || -z "$INPUT_DIR" || -z "$OUTPUT_DIR" ]]; then
    echo "Missing required arguments."
    echo "Usage: $0 -password=<password> -inputDir=<input_directory> -outputDir=<output_directory>"
    exit 1
fi

mkdir -p "$OUTPUT_DIR"

for file in "$INPUT_DIR"/*.pdf; do
  filename=$(basename "$file")
  
  qpdf --password="$PASSWORD" --decrypt "$file" "$OUTPUT_DIR/${filename%.pdf}_decrypted.pdf"
  
  echo "Decrypted $filename and saved as ${filename%.pdf}_decrypted.pdf in $OUTPUT_DIR."
done

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