Clean FLAC and MP3 tags

clean-tags.sh

#!/usr/bin/env bash
# ============================================================================
# clean-tags.sh
#
# Author: Jim Ing
# Date: 2024-11-19
#
# Description: This script processes audio files (.mp3 and .flac) to remove
#              specified metadata tags, displays metadata before and after
#              cleaning, and saves the cleaned files in a designated output
#              directory.

# Command-Line Options:
#   --dry-run: Simulates processing without modifying any files.
#   --output-dir DIR: Specifies a custom output directory.
#   --keywords "keyword1 keyword2": Custom keywords for metadata filtering.
# ============================================================================

# Define constants
DEFAULT_KEYWORDS="pmedia p.m.e.d.i.a k2nblog"
OUTPUT_DIR="cleaned"

# Flag to check if it's the first iteration
first=true

# Initialize counters for the summary report
processed_count=0
skipped_count=0
error_count=0

# Dry run mode flag
dry_run=false

# List of metadata tags to be cleared from audio files
metadata_tags=(
  "artists"
  "barcode"
  "catalog #"
  "catalog number"
  "comment"
  "compilation"
  "copyright"
  "credits"
  "encoded_by"
  "encoded-by"
  "encoder"
  "encodersettings"
  "grouping"
  "info"
  "isrc"
  "itunesadvisory"
  "label"
  "lyrics-eng"
  "organization"
  "performer"
  "pmedia"
  "provider"
  "publisher"
  "releasecountry"
  "source"
  "tbpm"
  "text"
  "thnx"
  "tit3"
  "tlen"
  "tmed"
  "toly"
  "tope"
  "tpe4"
  "trsn"
  "tsrc"
  "upload"
  "uploader"
  "work"
  "wwwaudiofile"
  "wwwaudiosource"
)

# Function to check prerequisites
check_prerequisites() {
  command -v ffmpeg >/dev/null || { echo "Error: ffmpeg is not installed."; exit 1; }
  command -v ffprobe >/dev/null || { echo "Error: ffprobe is not installed."; exit 1; }
}

# Function to create output directory
create_output_dir() {
  if [ ! -d "$OUTPUT_DIR" ]; then
    mkdir "$OUTPUT_DIR"
    echo "Directory '$OUTPUT_DIR' created."
  else
    echo "Directory '$OUTPUT_DIR' already exists."
  fi
}

# Function to process a single file
process_file() {
  local file="$1"
  echo "Processing file ($((processed_count + skipped_count + error_count + 1))/$total_files): $file"

  # Display input metadata
  echo "---[ Input Metadata ]---------------------------------------------------------"
  for keyword in "${keyword_array[@]}"; do
    ffprobe -i "$file" -show_entries format_tags -v quiet | grep -i "$keyword"
  done
  echo "------------------------------------------------------------------------------"

  if $dry_run; then
    echo "Dry run: Skipping metadata removal for $file."
    ((skipped_count++))
    return
  fi

  # Prepare metadata clearing arguments
  local clear_metadata_args=()
  for tag in "${metadata_tags[@]}"; do
    clear_metadata_args+=("-metadata" "$tag=")
  done

  # Remove metadata and save cleaned file
  if ffmpeg -i "$file" "${clear_metadata_args[@]}" -codec copy "$OUTPUT_DIR/$file" -loglevel warning; then
    ((processed_count++))
    echo "---[ Output Metadata ]--------------------------------------------------------"
    ffprobe -i "$OUTPUT_DIR/$file" -show_entries format_tags -v quiet -print_format flat
    echo "------------------------------------------------------------------------------"
  else
    echo "Error processing file: $file"
    ((error_count++))
  fi
}

# Function to display summary report
display_summary() {
  echo
  echo "------------------------------[ Summary Report ]------------------------------"
  echo "Total files found: $total_files"
  echo "Files processed:   $processed_count"
  echo "Files skipped:     $skipped_count"
  echo "Errors:            $error_count"
  echo "------------------------------------------------------------------------------"
}

# Parse command-line arguments
while [[ "$#" -gt 0 ]]; do
  case $1 in
    --dry-run) dry_run=true; shift ;;
    --output-dir) OUTPUT_DIR="$2"; shift 2 ;;
    --keywords) DEFAULT_KEYWORDS="$2"; shift 2 ;;
    *) echo "Unknown option: $1"; exit 1 ;;
  esac
done

# Parse keywords into an array
IFS=' ' read -r -a keyword_array <<< "${DEFAULT_KEYWORDS}"

# Start script execution
check_prerequisites

# Count total files for progress reporting
files=(*.mp3 *.flac)
total_files=0
for file in "${files[@]}"; do
  if [ -f "$file" ]; then
    ((total_files++))
  fi
done

if [ "$total_files" -eq 0 ]; then
  echo "No .mp3 or .flac files found in the current directory."
  exit 0
fi

# Create the output directory
create_output_dir

# Process each file
for file in "${files[@]}"; do
  if [ -f "$file" ]; then
    process_file "$file"

    # Ask the user whether to continue after processing the first file
    if [ "$first" = true ]; then
      first=false
      read -p "Please review the above output. Do you want to continue (y/n)? " user_input
      if [ "$user_input" != "y" ]; then
        echo "Exiting..."
        break
      else
        echo "Continuing..."
      fi
    fi
  fi
done

# Display summary report
display_summary

# TODO: Replace original files with cleaned files