analyze-file

# this shell script is sourced
#
# returns the format, bitrate and samplerate of a file 
# returns error 1 when the file is does not exist
#
analyze_file() {

    FILE="$1"
    # set soxi filter labels
    SOXISE="Sample Encoding: "
    SOXISR="Sample Rate    : "
    SOXIBD="Precision      : "

    if [ -f "${FILE}" ]; then
	
	FILENAME=$(basename "${FILE}")
	
	# call soxi one time per file
	FILEINFO=$(LANG=C soxi "${FILE}")
	FILESR=$(echo -e "${FILEINFO}" | grep "${SOXISR}" | sed "s#${SOXISR}##")
	FILEBD=$(echo -e "${FILEINFO}" | grep "${SOXIBD}" | sed "s#${SOXIBD}\(.*\)-bit#\1#")
	FILETYPE=$(echo -e "$FILEINFO" | grep "${SOXISE}" | sed "s#${SOXISE}${FILEBD}-bit \(.*\)#\1#")
	case "$FILETYPE" in
	    "FLAC")
		;;
	    *)
		die "Error: $FILE has an unknown filetype";;
	esac

	get_samplerate "$FILESR"
	get_bitdepth "$FILEBD"

	echo " \`$FILENAME': $FILETYPE, $FILESR Hz, $FILEBD bit"
	return 0

    else
	die "Error: no such file $FILE"
    fi
    
}

get_samplerate(){

# returns 0 when valid source has valid sample rate:
# '44100', 88200' or '176400'
# '48000', '96000'  or '192000' 
# dies when source has unknown sample rate

    VALIDRATES="'44100', '88200', '176400', '48000', '96000'  or '192000'"
    case "$1" in
	44100|88200|176400|48000|96000|192000) 
	    return 0 ;;
	*) 
	    die "Error: Invalid samplerate ($1) specified, use any of:\n" \
	    "       $VALIDRATES"
    esac
}


get_bitdepth(){

# returns 0 when bitdepth is valid
# dies when source file has unknown bit depth

    VALIDDEPTHS="'16', '18', '22' or '24'"
    case $1 in
	16|18|20|24) 
	    return 0 ;;
	*) 
	    die "Error: Invalid target bitdepth ($1 bits) specified, use any of:\n" \
	    "       $VALIDDEPTHS"
    esac

}