convert-flac

#!/bin/sh

#
# Copyright 2011, 2012 Ronald van Engelen <rvengelen@hethooghuis.nl>,
# distributed under the terms of the GNU General Public License
# version 2 or any later version.
# 

# set -e

usage() {
cat <<EOF
$0 [ -s | --samplerate <samplerate> ] [ -b | --bitdepth <bitdepth> ] [ <other options> ]  -- directory

Resamples flac or wav files in the current directory tot the specified
bit depth and sample rate. Defaults to only upsample to 96Khz/24bit.

  -s, --samplerate     Target sample rate in Hz (defaults to 96000)
  -b, --bitdepth       Target bit depth (defaults to 24)
  -l, --list           List sample rates of source flac files
  -d, --downsample     Limit resampling to downsampling (default: false)
  -u, --upsample       Limit resampling to upsampling (default: true)
  -p, --purge          Remove original flac files after resampling  (defaults to keep)
  -h, --help           Show this help message
EOF
}

analyze_command_line() {
    local done_opts

    while [ -z "$done_opts" ] ; do
        case "$1" in
            -b|--bitdepth) BITDEPTH=$(echo $2 | sed -e "s,',,g") ; shift 2 ;;
            -d|--downsample) DOWNSAMPLE=true; shift 1 ;;
            -h|--help) usage ; exit 0 ;;
            -l|--list) LIST=true ; shift 1 ;;
            -u|--upsample) UPSAMPLE=true; shift 1 ;;
            -p|--purge) PURGE=true; shift 1 ;;
            -s|--samplerate) SAMPLERATE=$(echo $2 | sed -e "s,',,g") ; shift 2 ;;
            *) 
		done_opts=true
		if [ ! -d "$@" ]; then
		    die "Error: Invalid path $@"
		fi
		;;
            #*) 
        esac
    done
    #DIR=$(echo "$@" | sed 's/\\//')
    DIR="${@}"
}

default_options() {

    if [ ! -n "$SAMPLERATE" ]; then
	SAMPLERATE="96000"
    fi

    if [ ! -n "$BITDEPTH" ]; then
	BITDEPTH="24"
    fi

    FLAC="$(which flac)"
    METAFLAC="$(which metaflac)"
    SSRC=ssrc_hp
    SSRCOPTS="--rate ${SAMPLERATE} --bits ${BITDEPTH} --twopass --quiet"
    SSRCOPTS="--rate ${SAMPLERATE} --bits ${BITDEPTH} --twopass"

    # Filename for the tarball containing the source flac files
    SRCFLACTAR="original-flacs.tar"
}


check_sourcedir() {
    echo "\tChecking sanity of directory ..."
    if [ -d "$DIR" ]; then
	if [ -w "$DIR" ]; then
	    if [ -f "$1/${SRCFLACTAR}" ]; then
		die "Error: It seems you have converted directory \`${DIR}' before. /
                     If not, remove \`${SRCFLACTAR}' and try again."
	    fi
	    FILES=$(find "$DIR" -maxdepth 1 -iname "*.flac" -or -iname "*.wav")

	    if [ -n "$FILES" ] ; then
		FILECOUNT=$(echo -e "${FILES}" | wc -l)
		echo "\tCheckes out OK: ${FILECOUNT} source files found"
	    else
		die "Error: No flac or wav files found in directory $DIR"
	    fi
	else
	    die "Error: No write permissions in directory $DIR"    
	fi
    else
	echo "Error: $DIR is not a directory"
    fi

}

list_sourcefiles() {
    
    echo "$FILES" | while read FILE
    do 
	#echo "$FILE"
	analyze_file "$FILE"
    done

}

convert_files() {

    # Temporary sub directory for storing intermediate files
    # will be cleaned afterwards
    echo " running convert_files on \"$1\":"
    TMPTARGET=$(mktemp -d "$1/original.XXXXXXXXXX")
    echo "  created temporary directory \"${TMPTARGET}\""

    # Save internal field separator of bash,
    # will be restored afterwards
    SAVEIFS=$IFS
    IFS=$(echo -en "\n\b")

    
    echo "$FILES" | while read FILE
    do 
	FILEOK=$(analyze_file "$FILE")
	if [ -n "$FILEOK" ]; then
	    convert_file "$FILE"
	else
	    die "Error: $FILE is not a usable audio file"
	fi
    done
    
    if [ -d "${TMPTARGET}" ]; then
	if $(tar cf "$1/${SRCFLACTAR}" "${TMPTARGET}"); then
	    rm -rf "${TMPTARGET}"
	    echo "Done!"
	    echo "... original flac files copied to tarball \"$1/${SRCFLACTAR}\""
	    echo "... resulting resampled flac files with metadata available in this directory"
	else
    	    echo "Error creating tarball of original flac files"
    	    echo "... please review the temporary files in \`${TMPTARGET}'"
	fi
    fi
    
    IFS=${SAVEIFS}

}

decode_flac() {

    # try to decode source flac to wav file in temp directory 
    echo "  running decode_flac with \"$1\" ($FILETYPE) and \"$2\" (PCM):"
    if $("${FLAC}" -s -d -o "$2" "$1"); then
        # move original FLAC to temporary directory
	mv "$1" "${TMPTARGET}"
	echo "  [ok]"
	return 0
    else
	die "Error: something went wrong while decoding flac source \"$1\" to \"$2\" ..."
    fi
}

resample_wav() {
    echo " running resample_wav with \"$1\" and \"$2\":"
    ssrc_hp --rate 96000 --bits 24 --twopass "$1" "$2"
    echo "  [ok]"
    # clean up original wav
    rm "$1"
    return 0
}


encode_toflac() {
    
    echo " running encode_toflac \"$1\" and \"$2\":"
    if $("${FLAC}" -s "$1" -o "$2" ); then
	echo " [ok]"
	# clean up resampled wav
	rm "$1"
	return 0
    else
	die "Error: something went wrong while encoding \"${RESAMPLEDWAVPATH}\" to \"${SOURCEFLACPATH}\" ..."
    fi
}

restore_flactags() {
    echo " running restore_flactags \"$1\" and \"$2\":"
    if $("${METAFLAC}" --export-tags-to - "$1" | "${METAFLAC}" --import-tags-from - "$2"); then
	echo " [ok]"
    else
	echo "Error: Could not restore flac tags to \"$2\" ... "
    fi
}

convert_file() {

    # /full/path/01file.flac
    INPUTFILEPATH="$1"
    # 01file.flac
    INPUTBASENAME=$(basename "${INPUTFILEPATH}")
    # flac
    INPUTEXTENSION="${INPUTBASENAME##*.}"
    # 01file
    INPUTNOEXT="${INPUTBASENAME%.*}"
    # /full/path
    INPUTDIRPATH=$(dirname "${INPUTFILEPATH}")
    # 01file.wav
    WAVFILENAME="${INPUTNOEXT}.wav"

    ORIGINALWAVPATH="${TMPTARGET}/${WAVFILENAME}"
    RESAMPLEDWAVPATH="${TMPTARGET}/Resampled ${WAVFILENAME}"
    TMPFLACPATH="${TMPTARGET}/${INPUTBASENAME}"
    

    echo " running convert_file on \"${INPUTFILEPATH}\""

    analyze_file "${INPUTFILEPATH}"

    echo "  converting from ${FILEBD}-bit/${FILESR} Hz to ${BITDEPTH}-bit/${SAMPLERATE} Hz"

    decode_flac "${INPUTFILEPATH}" "${ORIGINALWAVPATH}"

    resample_wav "${ORIGINALWAVPATH}" "${RESAMPLEDWAVPATH}"

    encode_toflac "${RESAMPLEDWAVPATH}" "${INPUTFILEPATH}"

    restore_flactags "${TMPFLACPATH}" "${INPUTFILEPATH}"

}

# Main

# Parse command line arguments
if ! ARGS=$(getopt -n "$0" -o +a:b:cdhmpr -l \
    'samplerate:,bitdepth:,list,upsample,downsample,purge,help' -- "$@"); then
    exit 1
fi

# source the generic functions
 . ./resample-commonfunctions
 . ./analyze-file

# include the configuration file if it exists
#if [ -f /etc/resample/resample.conf ]; then
#    . /etc/resample/resample.conf
#fi

# parse commandline parameters
analyze_command_line "$@"

# get defaults
default_options

# check existence of programs
check_sanity


#if [ $LIST ]; then
#    list_sourcefiles
#fi


# verify samplerate and bitdepth
#get_samplerate $SAMPLERATE
#get_bitdepth $BITDEPTH


echo "Preparing to process $DIR"
# check sanity of source dir
check_sourcedir  "$DIR"
#list_sourcefiles "$DIR"
convert_files "$DIR"