#!/bin/bash
#set -n		# read but do not execute commands (check on syntax errors)
#
# File: /usr/local/bin/audiofilter-stereotools.
#
# Apply the stereotools filter.
#
#    Copyright (c) 2023  Juergen Kaesmann (JK)
#
##############################################################################
# GPL NOTICE
#
#    This program is free software; you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation; either version 2 of the License, or
#    (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program; if not, write to the Free Software
#    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
##############################################################################
# FIND SAMPLES
#
##############################################################################
# FILTER SAMPLES
#
# To avoid spaces (shell) surround filter and arguments with ""
# There are two filter types:
# a) Simple filter
#	-filter:a|-filter:v "<filter>=<arguments_list>"
#	or
#	-af|-vf "<filter>=<arguments_list>"
# b) Complex filter
#	-filter_complex "[<arguments_list>]<filter>=<arguments_list>"
#
#-----------------------------------------------------------------------------
# SETPTS filter explanation:
# setpts	Set timestamps.
#
# generate video timestamps from zero:
# -filter:v "trim" -filter:v "setpts=PTS-STARTPTS"
#
# generate audio timestamps from zero:
# -filter:a "atrim" -filter:a "asetpts=PTS-STARTPTS"
#
#-----------------------------------------------------------------------------
# VOLUME filter explanation:
# volume	Adjust the volume. Do not set the volume.
#
# increase volume by 150%:
# -filter:a "volume=1.5"
#
# increase volume by 10dB:
# -filter:a "volume=10dB"
#
# reduce volume by 5dB, use a negative value:
# -filter:a "volume=-5dB"
#
#-----------------------------------------------------------------------------
# PEAK and RMS Normalization:
# volume	Adjust the volume to a peak or RMS level.
#
# To normalize the volume to a given peak or RMS level, the file first has to
# be analyzed with filter a) or b):
# a) -filter:a volumedetect
# b) -filter_complex [0:a]ebur128=peak=sample
#
# Read the output values from the command line log (relative to max value)
# and calculate the required offset to adjust max_volume/PEAK to 0.
# Then change the volume with the filter:
# -filter:a "volume=<offset>dB"
#
# or normalize the file with:
# -af "dynaudnorm=<...>"
#
#-----------------------------------------------------------------------------
# COMPANDER explanation:
# compand	Compress or expand the audio's dynamic range.
#
# Show compand params - separate every PART with ':'
# PARTS		DEFAULTS		MODE "s"
# attack lst	0.3 0.3			0 0
# decay lst	0.8 0.8			1 1
# points lst	-70/-70 -60/-60 1/0	-90/-900 -70/-70 -30/-9 0/-3
# soft-knee	0.01			6
# gain		0			0
# volume	0			0
# delay		0			0
#
# Using simple audiofilter:
# -af "aformat=channel_layouts=stereo, compand=0 0:1 1:-90/-900 -70/-70 -30/-9 0/-3:6:0:0:0"
#
# Using complex audiofilter:
# -filter_complex "compand=0 0:1 1:-90/-900 -70/-70 -30/-9 0/-3:6:0:0:0"
#
# same as above but avoid SPACES:
# -filter_complex compand=0|0:1|1:-90/-900|-70/-70|-30/-9|0/-3:6:0:0:0
#
#-----------------------------------------------------------------------------
# EQUALIZER explanation:
# equalizer	Apply a two-pole peaking equalisation (EQ) filter.
#
# With this filter, the signal-level at and around a selected frequency can
# be increased or decreased, whilst (unlike bandpass and bandreject filters)
# that at all other frequencies signal is unchanged.
#
# In order to produce complex equalisation curves, this filter can be
# given several times, each with a different central frequency and separated
# with a comma.
#
# The filter accepts the following options:
# frequency, f	Set the filter's central frequency in Hz.
# width_type	Set method to specify band-width of filter.
# 	h	Hz
# 	q	Q-Factor
# 	o	octave
# 	s	slope
# width, w	Specify the band-width of a filter in width_type units.
#		Have in mind that the frequency is limited to 999 Hz.
# gain, g	Set the required gain or attenuation in dB.
# 		Beware of clipping when using a positive gain.
#
# Examples:
# Attenuate 10 dB at 1000 Hz, with a bandwidth of 200 Hz:
# -af equalizer=f=1000:width_type=h:width=200:g=-10
#
# Apply 2 dB gain at 1000 Hz with Q 1 and attenuate 5 dB at 100 Hz with Q 2:
# -af equalizer=f=1000:width_type=q:width=1:g=2,equalizer=f=100:wid
#
# Apply 6 dB gain at 200 Hz and width 300 Hz:
# -af equalizer=f=200:width_type=h:w=300:g=6
#
# Sound Distribution:
# BAND		TYPE
# 16-100	Sub Bass
# 50-250	Bass
# --------------------------
# 250-2k	Low Midd
# 2k-4k		High Midd
# --------------------------
# 4k-6k		Präsenz
# 6k-16k	Brillanz
#
# Template EQ with 18 bands non-overlaping
# BAND		f	w
# 50-100	75	50
# 100-250	175	150
# 250-1k	625	750
# 1k-2k		1500	999
# 2k-3k		2500	999
# 3k-4k		3500	999
# 4k-5k		4500	999
# 5k-6k		5500	999
# 6k-7k		6500	999
# 7k-8k		7500	999
# 8k-9k		8500	999
# 9k-10k	9500	999
# 10k-11k	10500	999
# 11k-12k	11500	999
# 12k-13k	12500	999
# 13k-14k	13500	999
# 14k-15k	14500	999
# 15k-16k	15500	999
# -af equalizer=f=75:width_type=h:w=50:g=0,equalizer=f=175:width_type=h:w=150:g=0,equalizer=f=625:width_type=h:w=750:g=0,equalizer=f=1500:width_type=h:w=999:g=0,equalizer=f=2500:width_type=h:w=999:g=0,equalizer=f=3500:width_type=h:w=999:g=0,equalizer=f=4500:width_type=h:w=999:g=0,equalizer=f=5500:width_type=h:w=999:g=0,equalizer=f=6500:width_type=h:w=999:g=0,equalizer=f=7500:width_type=h:w=999:g=0,equalizer=f=8500:width_type=h:w=999:g=0,equalizer=f=9500:width_type=h:w=999:g=0,equalizer=f=10500:width_type=h:w=999:g=0,equalizer=f=11500:width_type=h:w=999:g=0,equalizer=f=12500:width_type=h:w=999:g=0,equalizer=f=13500:width_type=h:w=999:g=0,equalizer=f=14500:width_type=h:w=999:g=0,equalizer=f=15500:width_type=h:w=999:g=0
#
#-----------------------------------------------------------------------------
# ANEQUALIZER explanation:
# anequalizer	High-order parametric multiband equalizer for each channel.
#
# This option string is in format: "c<chn> f=<cf> w=<bw> g=<bg> t=<ft> | ..."
# Each equalizer band is separated by '|'.
#
# chn	Channel number to which equalization will be applied (0|1 for stereo).
#	If input doesn't have that channel the entry is ignored.
# cf	Central frequency for band.  If input doesn't have that
#	frequency the entry is ignored.
# bw	Band width in hertz.
# bg	Band gain in dB.
# ft	Filter type for band, optional, can be:
#	0	Butterworth, this is default.
#	1	Chebyshev type 1.
#	2	Chebyshev type 2.
#
# Examples:
# Lower gain by 10 of central frequency 200Hz and width 100 Hz for
# first 2 channels using Chebyshev type 1 filter:
# -af "anequalizer=c0 f=200 w=100 g=-10 t=1|c1 f=200 w=100 g=-10 t=1"
#
# Rise gain by 6 dB of central frequency 200 Hz and width 300 Hz for
# first 2 channels using Butterworth type 0 filter:
# -af "anequalizer=c0 f=200 w=300 g=6 t=0|c1 f=200 w=300 g=6 t=0"
#
#-----------------------------------------------------------------------------
# AFADE filter explanation:
# afade		Apply fade-in/out effect to input audio.
#
# type, t
#   Specify the effect type, can be either "in" for fade-in, or "out"
#   for a fade-out effect. Default is "in".
#
# start_time, st
#   Specify the start time of the fade effect. Default is 0.  The value
#   must be specified as a time duration; see the Time duration section
#   in the ffmpeg-utils(1) manual for the accepted syntax.
#
# duration, d
#   Specify the duration of the fade effect. See the Time duration
#   section in the ffmpeg-utils(1) manual for the accepted syntax.  At
#   the end of the fade-in effect the output audio will have the same
#   volume as the input audio, at the end of the fade-out transition
#   the output audio will be silence.
#
# curve
#   Set curve for fade transition.
#   It accepts the following values:
#     tri	select triangular, linear slope (default)
#     qsin	select quarter of sine wave
#     hsin	select half of sine wave
#     esin	select exponential sine wave
#     log	select logarithmic
#     ipar	select inverted parabola
#     qua	select quadratic
#     cub	select cubic
#     squ	select square root
#     cbr	select cubic root
#     par	select parabola
#     exp	select exponential
#     iqsin	select inverted quarter of sine wave
#     ihsin	select inverted half of sine wave
#     dese	select double-exponential seat
#     desi	select double-exponential sigmoid
#
# Examples:
# Fade in first 1 second of audio:
# -af "afade=t=in:st=0:d=1"
# Fade out last 3 seconds of a 180 seconds audio:
# -af "afade=t=out:st=177:d=3"
#
#-----------------------------------------------------------------------------
# ATEMPO filter explanation:
# atempo - Adjust audio tempo.
#
# The filter accepts exactly one parameter, the audio tempo. If not
# specified then the filter will assume nominal 1.0 tempo. Tempo must be
# in the [0.5, 2.0] range.
#
# Examples:
# Slow down audio to 80% tempo:
# -af "atempo=0.8"
# To speed up audio to 125% tempo:
# -af atempo=1.25
#
##############################################################################
# AWK SAMPLES
#
##############################################################################
# SED SAMPLES
#
##############################################################################
# RSYNC OPTIONS
#
##############################################################################
# DIALOG SAMPLES
#
##############################################################################
# REPLACE STRINGS
#
##############################################################################
# EXIT CODES

##############################################################################
# SOURCE FILES
#
. /usr/local/etc/main.conf				# config main
#. $LLIBDIR/libfuncerr-sh				# functions error
. $LLIBDIR/libfuncstd-sh				# functions standard
#. $LLIBDIR/libfuncmath-sh				# functions math
#. $LLIBDIR/libfuncip-sh				# functions IP
#. /usr/local/etc/sample.conf				# config sample
#
#if [ ! -e ~/.samplerc ]; then				# install config user
#	cp /usr/local/share/ksm-sample/samplerc ~/.samplerc
#fi
#. ~/.samplerc						# config user

##############################################################################
# DECLARATION OF STANDARD CONSTANTS AND VARIABLES
#
readonly package=Multimedia				# package name
readonly package_file=ksm-multimedia			# package file name
readonly vinfopath="/usr/local/share/$package_file"	# path to package dir
readonly version=$(/bin/cat $vinfopath/VERSION)		# package version
readonly release=$(/bin/cat $vinfopath/RELEASE)		# package release
readonly scriptname=$(basename $0)			# name of script
#readonly tempfile=$TEMPDIR/$scriptname.$UID.tmp	# temporary file name
#tempfile=$(mktemp $TEMPDIR/$scriptname.$UID.XXXXXX)	# temporary file name
#readonly lockfile=$TEMPDIR/lock/$scriptname.$UID.lock	# lock file name
readonly debuglog="/usr/bin/logger -p user.debug -t $scriptname -- DEBUG:"	# log dbg msg
readonly errlog="/usr/bin/logger -p user.err -t $scriptname -- ERROR:"		# log err msg
readonly infolog="/usr/bin/logger -p user.info -t $scriptname -- INFO:"		# log inf msg
cmd=''							# sub command
debug=no						# debug=yes/no
verbose=''						# verbose=yes/''/no
err=${_ERR_OK_}						# error code

##############################################################################
# USER FILL IN AT FIRST RUN

##############################################################################
# SYSTEM

##############################################################################
# USER-CONSTANTS

##############################################################################
# USER-VARIABLES
#
# STRINGS
#args=''				# all args from cmdline
arg1=''					# 1. arg from cmdline
arg2=''					# 2. arg from cmdline
arg3=''					# 3. arg from cmdline
#opt_o=''				# option -o (yes)
					# option --output (yes)
#opt_i=''				# option -i (arg)
					# option --infile (arg)
#opt_o=''				# option -o (arg)
					# option --outfile (arg)
#opt_p=''				# option -p (arg)
					# option --pages (arg)
f=''

# NUMBERS
#p_first=0				# first page
#p_last=0				# last page

# ARRAYS
# Indexed arrays are always zero based string arrays.
# If index starts with 1 and all members are assigned then
# count of members of array = last index of array
#declare -a arr
#maxarr="${#arr[@]}"			# get number of elements in arr
#unset arr[@]				# remove the entire array

##############################################################################
# LANGUAGE SUPPORT

##############################################################################
# SIGNAL HANDLING

##############################################################################
# FUNCTIONS
##############################################################################
#
##############################################################################
# HELP
#
#=============================================================================
function helptext ()
{
# Output helptext
# Uses cat, echo, logger
# Return codes:
# Standard

if [ "$debug" == "yes" ]; then				# DEBUG
	echo "DEBUG helptext: $# $@" >&2
	$debuglog helptext: $# $@
fi

cat <<EOT
NAME
$scriptname - Apply the stereotools filter.

SYNOPSIS
$scriptname [options] [par inf [outf]]

<AUDIOSTREAM> | $scriptname [options] par inf outf

DESCRIPTION
Apply the stereotools filter to an MP3 file or to an MP3 stream.

If <inf> is given but <outf> is not given then the outfile is generated
from <inf> prepended with 'n'.

If <inf> is a '-' then we process an incoming audio stream (type nut)
from STDIN.

If <outf> is a '-' then we stream the audio to STDOUT (stream type is
nut).

FFMPEG INFO
This filter has some utilities to manage stereo signals.

stereotools=level_in=1:level_out=1:balance_in=0:balance_out=0:...

This filter has some handy utilities to manage stereo signals, for
converting M/S stereo recordings to L/R signal while having control
over the parameters or spreading the stereo image of master track.

The filter accepts the following options:

level_in  
    Set input level before filtering for both channels. Defaults is 1.
    Allowed range is from 0.015625 to 64.

level_out  
    Set output level after filtering for both channels. Defaults is 1.
    Allowed range is from 0.015625 to 64.

balance_in  
    Set input balance between both channels. Default is 0. Allowed
    range is from -1 to 1.

balance_out  
    Set output balance between both channels. Default is 0. Allowed
    range is from -1 to 1.

softclip  
    Enable softclipping. Results in analog distortion instead of harsh
    digital 0dB clipping. Disabled by default.

mutel  
    Mute the left channel. Disabled by default.

muter  
    Mute the right channel. Disabled by default.

phasel  
    Change the phase of the left channel. Disabled by default.

phaser  
    Change the phase of the right channel. Disabled by default.

mode  
    Set stereo mode. Available values are:

    lr>lr  
       Left/Right to Left/Right, this is default.

    lr>ms  
       Left/Right to Mid/Side.

    ms>lr  
       Mid/Side to Left/Right.

    lr>ll  
       Left/Right to Left/Left.

    lr>rr  
       Left/Right to Right/Right.

    lr>l+r  
       Left/Right to Left + Right.

    lr>rl  
       Left/Right to Right/Left.

slev  
    Set level of side signal. Default is 1. Allowed range is from
    0.015625 to 64.

sbal  
    Set balance of side signal. Default is 0. Allowed range is from -1
    to 1.

mlev  
    Set level of the middle signal. Default is 1. Allowed range is
    from 0.015625 to 64.

mpan  
    Set middle signal pan. Default is 0. Allowed range is from -1 to 1.

base  
    Set stereo base between mono and inversed channels. Default is 0.
    Allowed range is from -1 to 1.

delay  
    Set delay in milliseconds how much to delay left from right channel
    and vice versa. Default is 0. Allowed range is from -20 to 20.

sclevel  
    Set S/C level. Default is 1. Allowed range is from 1 to 100.

phase  
    Set the stereo phase in degrees. Default is 0. Allowed range is
    from 0 to 360.

OPTIONS
Gnu style options:

  -h|--help    = Output help, then exit.
  -V|--version = Output version info, then exit.
  -d|--debug   = Turn on DEBUG mode.
  -q|--quiet   = Be quiet.
  -v|--verbose = Be verbose.
  -a           = Process all MP3s in actual dir (supply only <par>).
  --           = End of options.

ARGUMENTS
Give if needed:

  par  = The parameter to supply
         'level_in=1:level_out=1:balance_in=0:balance_out=0:mode=lr>ms'
  inf  = The input file name or a '-'
  outf = The output file name or a '-'

EXAMPLES
For instance:

  Use stereotools and change stereo mode:
  $scriptname 'mode=lr>ms' INFILE.mp3 OUTFILE.mp3

EXIT STATUS
On program exit:

  Code 0 = OK

  See output of 'showerrmsg'.

SEE ALSO
Related manpages:

  showerrmsg(1), ffmpeg(1), media2media(1),
  audiofilter-bandpass(1), audiofilter-bandreject(1), 
  audiofilter-bass(1), audiofilter-chorus(1), 
  audiofilter-compand(1), audiofilter-crossfade(1), 
  audiofilter-dynaudnorm(1), audiofilter-dynvol(1), 
  audiofilter-earwax(1), audiofilter-echo(1), 
  audiofilter-extrastereo(1), audiofilter-fade(1), 
  audiofilter-flanger(1), audiofilter-gate(1), 
  audiofilter-highpass(1), audiofilter-limiter(1), 
  audiofilter-lowpass(1), audiofilter-phaser(1), 
  audiofilter-pulsator(1), audiofilter-rubberband(1), 
  audiofilter-stereowiden(1), 
  audiofilter-tempo(1), audiofilter-treble(1), 
  audiofilter-tremolo(1), audiofilter-vibrato(1), 
  audiofilter-volcomp(1), audiofilter-volume(1).

AUTHORS
Juergen Kaesmann <juergen@kaesmann-online.de>
EOT
#  -o|--output  = Output to STDOUT.
#  -i f         = Input from file <f>.
#  --infile=f   = Input from file <f>.
#  -o f         = Output to file <f>.
#  --outfile=f  = Output to file <f>.
#  -p s,e       = Pages s=START e=END.
#  --pages=s,e  = Pages s=START e=END.

#FILES
#Used directories and files:
#
#  Config global = /usr/local/etc/multimedia.conf

return
}

#=============================================================================
function mainproc ()
{
# Apply stereotools filter to the given file.
# par1 = par
# par2 = inf
# Uses echo, logger
# Return codes:
# Standard

if [ "$debug" == "yes" ]; then				# DEBUG
	echo "DEBUG mainproc: $# $@" >&2
	$debuglog mainproc: $# $@
fi

local par="$1" inf="$2" outf="" pre=""
local ret=0
#local -a arr
#maxarr="${#arr[@]}"			# get number of elements in arr
#unset arr[@]				# remove the entire array

if [ "$inf" != '-' ] && [ -z "$arg3" ]; then
	outf="n${inf}"
else
	outf="$arg3"
fi
                
if [ "$inf" != '-' ]; then				# input from file
	if [ "$outf" != '-' ]; then			# store to file
		case "$verbose" in
		    yes)				# allow STDOUT and STDERR
			echo "Run $scriptname"
			ffmpeg -i $inf -af "stereotools=${par}" -c:v copy $pre -id3v2_version 3 -write_id3v1 1 $outf
			ret=$?
			;;
		    '')					# suppress STDOUT or STDERR
			#echo "Run $scriptname"
			ffmpeg -hide_banner -i $inf -af "stereotools=${par}" -c:v copy $pre -id3v2_version 3 -write_id3v1 1 $outf 2>/dev/null
			#1>/dev/null
			ret=$?
			;;
		    no)					# suppress STDOUT and STDERR
			ffmpeg -hide_banner -y -i $inf -af "stereotools=${par}" -c:v copy $pre -id3v2_version 3 -write_id3v1 1 $outf &>/dev/null
			ret=$?
			;;
		esac
	else						# pipe to STDOUT
		ffmpeg -hide_banner -y -i $inf -af "stereotools=${par}" -c:v copy -id3v2_version 3 -write_id3v1 1 -f nut - 2>/dev/null
		ret=$?
	fi
else							# input from STDIN
	if [ "$outf" != '-' ]; then			# store to file
		case "$verbose" in
		    yes)				# allow STDOUT and STDERR
			echo "Run $scriptname"
			ffmpeg -f nut -i $inf -af "stereotools=${par}" -c:v copy $pre -id3v2_version 3 -write_id3v1 1 $outf
			ret=$?
			;;
		    '')					# suppress STDOUT or STDERR
			#echo "Run $scriptname"
			ffmpeg -hide_banner -f nut -i $inf -af "stereotools=${par}" -c:v copy $pre -id3v2_version 3 -write_id3v1 1 $outf 2>/dev/null
			#1>/dev/null
			ret=$?
			;;
		    no)					# suppress STDOUT and STDERR
			ffmpeg -hide_banner -y -f nut -i $inf -af "stereotools=${par}" -c:v copy $pre -id3v2_version 3 -write_id3v1 1 $outf &>/dev/null
			ret=$?
			;;
		esac
	else						# pipe to STDOUT
		ffmpeg -hide_banner -y -f nut -i $inf -af "stereotools=${par}" -c:v copy -id3v2_version 3 -write_id3v1 1 -f nut - 2>/dev/null
		ret=$?
	fi
fi

if [ "$ret" -ne 0 ]; then				# from ffmpeg
	Show_Err ${_ERR_GENERAL_} "$ret from ffmpeg!"
	ret=${_ERR_GENERAL_}
fi

return $ret
}

##############################################################################
# GET OPTIONS
##############################################################################
# Give 2 strings and all cmdline_args to func GetOpt
# (POSIX_options Gnu_long_options cmdline_args):
# GetOpt 'hVdqvi:m:' 'help version debug quiet verbose infile= myval=' $@
#
# A ':' after a POSIX option means this option needs an arg.
# A '=' after a Gnu long option means this option needs an arg.
#
# All cmd/options have to be initialised to ''!
#
# POSIX options are classified in 2 categories:
#   a) cmds (mutually exclusive). All cmds are given to var 'cmd'.
#   b) options (as many as you like). Each option is given to it's own var.
# As a general rule: If cmds/options are given multiple then last given wins.
#
# Options can take 1 argument (no whitespace in arg). If you want to give more
# than 1 arg or want to use multiple strings as 1 arg then concatenate them
# together with a delimiter like ',' or ';' or '.'
# Use a delimiter which will not be part of the arg:
# sampleprog -m val1,val2
# sampleprog --myval=val1,val2
# It's at the programmers responsibility to do meaningfull things with the
# content of the options.
#
# If err != 0 then all args are processed, else continue to look for options.
# When GetOpt finishes then all options are removed from cmdline.
#
if [ "$debug" == "yes" ]; then				# DEBUG
	echo "DEBUG Parse Commandline: $# $@" >&2
	$debuglog Parse Commandline: $# $@
fi
#
err=${_ERR_OK_}
while [ "$err" -eq 0 ]; do
	GetOpt 'hVdqva' 'help version debug quiet verbose' $@
	err=$?
	#echo "DEBUG GET OPTIONS: err=${err}  _OPTNAME_=${_OPTNAME_}  _OPTVAL_=${_OPTVAL_}  _OPTPOS_=${_OPTPOS_}  _OPTIDX_=${_OPTIDX_}" >&2
	if [ $err -eq 0 ]; then
		case "$_OPTNAME_" in
		    h|help)	cmd="-h";;
		    V|version)	cmd="-V";;
		    a)		cmd="-${_OPTNAME_}";;
		    d|debug)	debug=yes;;
		    q|quiet)	verbose=no;;
		    v|verbose)	verbose=yes;;
#		    o|output)	opt_o=yes;;
#		    i|infile)	opt_i="${_OPTVAL_}";;
#		    o|outfile)	opt_o="${_OPTVAL_}";;
#		    p|pages)	opt_p="${_OPTVAL_}";;
		    --)		break;;
		    :)	Show_Err ${_ERR_MISSING_ARG_FOR_OPT_} "-${_OPTVAL_}"
			exit ${_ERR_MISSING_ARG_FOR_OPT_};;
		    ?)	Show_Err ${_ERR_UNKNOWN_OPT_} "-${_OPTVAL_}"
			exit ${_ERR_UNKNOWN_OPT_};;
		    *)	Show_Err ${_ERR_UNKNOWN_ERR_} "_OPTNAME_=${_OPTNAME_} _OPTVAL_=${_OPTVAL_}"
			exit ${_ERR_UNKNOWN_ERR_};;
		esac
	fi
done
err=${_ERR_OK_}
shift ${_OPTIDX_}				# rm all opts from cmdline
#
# Uncomment if giving a cmd is mandatory
#if [ -z "$cmd" ]; then					# error no cmd given
#	Show_Err ${_ERR_MISSING_SUB_CMD_} ""
#	exit ${_ERR_MISSING_SUB_CMD_}
#fi

##############################################################################
# CHECK LINK NAMES

##############################################################################
# CHECK OPTIONS

##############################################################################
# CHECK VERSION

##############################################################################
# CHECK ARGUMENTS
#
case "$cmd" in
    '')
	if [ "$#" -eq 2 ]; then				# parameter count ok
		arg1="$1"
		arg2="$2"
		shift 2
		#args="$@"
		#shift $#
	elif [ "$#" -eq 3 ]; then			# parameter count ok
		arg1="$1"
		arg2="$2"
		arg3="$3"
		shift 3
	else						# error in param count
		Show_Err ${_ERR_WRONG_PAR_COUNT_} ""
		exit ${_ERR_WRONG_PAR_COUNT_}
	fi
	;;
    -a)
	if [ "$#" -eq 1 ]; then				# parameter count ok
		arg1="$1"
		shift
	else						# error in param count
		Show_Err ${_ERR_WRONG_PAR_COUNT_} ""
		exit ${_ERR_WRONG_PAR_COUNT_}
	fi
	;;
    *)
	if [ "$#" -ne 0 ]; then				# error in param count
		Show_Err ${_ERR_WRONG_PAR_COUNT_} ""
		exit ${_ERR_WRONG_PAR_COUNT_}
	fi
	;;
esac

##############################################################################
# LOCK

##############################################################################
# MAINPROGRAM
##############################################################################
#
if [ "$debug" == "yes" ]; then				# DEBUG
	echo "DEBUG Main: $# $@" >&2
	$debuglog Main: $# $@
fi
#
# Check what to do (sub commands, options and args are removed from cmdline)
case "$cmd" in
    '')
	mainproc $arg1 $arg2
	err=$?
	;;
    -h)
	helptext
	exit 0
	;;
    -V)
	echo "${scriptname}: (${package}) $package_file ${version}-${release}"
	exit 0
	;;
    -a)
	for f in *.mp3; do
		mainproc $arg1 "$f"
	done
	err=$?
	;;
    *)							# error
	Show_Err ${_ERR_SUB_CMD_NOT_FOUND_} ""
	err=${_ERR_SUB_CMD_NOT_FOUND_}
	;;
esac

#rm -f $lockfile

exit $err
