Convert FLAC audio files to MP3 format using FFmpeg.

flac2mp3.sh

#!/bin/sh

# flac2mp3 - Convert FLAC files to MP3 format (POSIX sh compatible)
# Version: 1.0
# Author: Albz <alberto.barrago@gmail.com>

VERSION="1.0"
BITRATE="320k"
QUIET=false
VERBOSE=false
PRESERVE_FLAC=true

# Color codes for output (if terminal supports it)
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m'

usage() {
    cat << EOF
Usage: $(basename "$0") [OPTIONS] FILE|DIRECTORY...

Convert FLAC audio files to MP3 format using FFmpeg.

ARGUMENTS:
    FILE|DIRECTORY    One or more FLAC files or directories containing FLAC files

OPTIONS:
    -b RATE           Set MP3 bitrate (default: 320k)
                      Common values: 128k, 192k, 256k, 320k
    -d                Delete original FLAC files after conversion
    -q                Suppress non-error output
    -v                Show detailed conversion information
    -h                Display this help message
    -V                Display version information

EXAMPLES:
    $(basename "$0") song.flac
    $(basename "$0") -b 192k song1.flac song2.flac
    $(basename "$0") -d music_directory/

EOF
    exit 0
}

show_version() {
    echo "flac2mp3 version $VERSION"
    exit 0
}

check_ffmpeg() {
    if ! command -v ffmpeg >/dev/null 2>&1; then
        printf "${RED}Error: FFmpeg is not installed or not in PATH${NC}\n" >&2
        echo "Please install FFmpeg: https://ffmpeg.org/download.html" >&2
        exit 1
    fi
}

log() {
    if [ "$QUIET" = "false" ]; then
        printf "%b\n" "$@"
    fi
}

convert_file() {
    input_file="$1"
    output_file="${input_file%.flac}.mp3"
    
    if [ ! -f "$input_file" ]; then
        printf "${RED}Error: File not found: %s${NC}\n" "$input_file" >&2
        return 1
    fi
    
    case "$input_file" in
        *.flac) ;;
        *)
            printf "${YELLOW}Warning: Skipping non-FLAC file: %s${NC}\n" "$input_file" >&2
            return 1
            ;;
    esac
    
    if [ -f "$output_file" ]; then
        log "${YELLOW}Warning: $output_file already exists, skipping...${NC}"
        return 0
    fi
    
    log "${GREEN}Converting:${NC} $(basename "$input_file")"
    
    if [ "$VERBOSE" = "false" ]; then
        ffmpeg -i "$input_file" -ab "$BITRATE" -map_metadata 0 -id3v2_version 3 -loglevel error "$output_file" 2>&1
    else
        ffmpeg -i "$input_file" -ab "$BITRATE" -map_metadata 0 -id3v2_version 3 "$output_file" 2>&1
    fi
    
    if [ $? -eq 0 ]; then
        log "${GREEN}✓ Success:${NC} $(basename "$output_file")"
        
        if [ "$PRESERVE_FLAC" = "false" ]; then
            rm "$input_file"
            log "${YELLOW}  Deleted original FLAC file${NC}"
        fi
        return 0
    else
        printf "${RED}✗ Failed:${NC} %s\n" "$(basename "$input_file")" >&2
        return 1
    fi
}

process_directory() {
    dir="$1"
    count=0
    success=0
    failed=0
    
    if [ ! -d "$dir" ]; then
        printf "${RED}Error: Directory not found: %s${NC}\n" "$dir" >&2
        return 1
    fi
    
    log "${GREEN}Processing directory:${NC} $dir"
    
    # Use find with exec to handle files properly
    found_files=0
    
    find "$dir" -maxdepth 1 -type f -name "*.flac" -print0 2>/dev/null | while IFS= read -r -d '' file
    do
        found_files=1
        count=$((count + 1))
        if convert_file "$file"; then
            success=$((success + 1))
        else
            failed=$((failed + 1))
        fi
    done
    
    # Alternative method if the above doesn't work - using a different approach
    if [ $? -ne 0 ]; then
        # Fallback: use ls with proper quoting
        find "$dir" -maxdepth 1 -type f -name "*.flac" 2>/dev/null | while IFS= read -r file
        do
            count=$((count + 1))
            if convert_file "$file"; then
                success=$((success + 1))
            else
                failed=$((failed + 1))
            fi
        done
    fi
    
    if [ $count -eq 0 ]; then
        log "${YELLOW}No FLAC files found in: $dir${NC}"
        return 0
    fi
    
    log "\n${GREEN}Directory summary:${NC} $success succeeded, $failed failed out of $count files\n"
    
    [ $failed -eq 0 ] && return 0 || return 1
}

main() {
    total_success=0
    total_failed=0
    has_error=false
    
    check_ffmpeg
    
    if [ $# -eq 0 ]; then
        usage
    fi
    
    # Parse arguments
    while [ $# -gt 0 ]; do
        case "$1" in
            -h)
                usage
                ;;
            -V)
                show_version
                ;;
            -b)
                shift
                if [ -z "$1" ]; then
                    printf "${RED}Error: -b requires an argument${NC}\n" >&2
                    exit 1
                fi
                BITRATE="$1"
                ;;
            -d)
                PRESERVE_FLAC=false
                ;;
            -q)
                QUIET=true
                ;;
            -v)
                VERBOSE=true
                ;;
            -*)
                printf "${RED}Error: Unknown option: %s${NC}\n" "$1" >&2
                echo "Use -h for usage information"
                exit 1
                ;;
            *)
                break
                ;;
        esac
        shift
    done
    
    if [ $# -eq 0 ]; then
        printf "${RED}Error: No files or directories specified${NC}\n" >&2
        usage
    fi
    
    log "${GREEN}Starting conversion with bitrate: $BITRATE${NC}\n"
    
    for item in "$@"; do
        if [ -f "$item" ]; then
            if convert_file "$item"; then
                total_success=$((total_success + 1))
            else
                total_failed=$((total_failed + 1))
                has_error=true
            fi
        elif [ -d "$item" ]; then
            if ! process_directory "$item"; then
                has_error=true
            fi
        else
            printf "${RED}Error: Not found: %s${NC}\n" "$item" >&2
            has_error=true
        fi
    done
    
    if [ $total_success -gt 0 ] || [ $total_failed -gt 0 ]; then
        log "\n${GREEN}=== Conversion Complete ===${NC}"
        [ $total_success -gt 0 ] && log "${GREEN}Successfully converted: $total_success files${NC}"
        [ $total_failed -gt 0 ] && log "${RED}Failed conversions: $total_failed files${NC}"
    fi
    
    if [ "$has_error" = "true" ]; then
        exit 1
    fi
    
    exit 0
}

main "$@"