mpvc-equalizer

#!/usr/bin/env sh
#
# @file mpvc-equalizer
# @description mpvc equalizer based on firequalizer15.lua
# @author gmt4 <gmt4 at github.com> (c) Copyright 2022 GPLv2+
# @url github.com/gmt4/mpvc
# SPDX-License-Identifier: GPL-2.0-or-later
#

PROGNAME=${0##*/}
PROGDIR=${0%/*}
PROGVERSION="v1.6"
PROGAUTHOR=gmt4
PROGURL="https://github.com/gmt4/mpvc"

set -euf

MPVC_LABEL="${MPVC_LABEL:-mpvc-equalizer}"
MPVC_FREQ_TABLE="0  65 157 288 472 733 1k1 1k6 2k4 3k4 4k9 7k0 10k 14k 20k"
MPVC_GAIN_TABLE="0   0   0   0   0   0   0   0   0   0   0   0   0   0   0"

mpvc() { "$PROGDIR/mpvc" "$@"; } # mpvc-web?

mpvc_genfilter()
{
    awk -v quote="'" -v gain_curr="$*" -v freq_table_str="MPVC_FREQ_TABLE" -v gain_table_str="$MPVC_GAIN_TABLE" \
    '
    BEGIN {
      num_entry=15
      min_val = -360
      max_val = 120

      n=split(freq_table_str, freq_table)
      n=split(gain_table_str, gain_table)
      if (gain_curr)
          n=split(gain_curr, gain_table)
    }

    function min(a,b) {return (a<b)?a:b;}
    function max(a,b) {return (a>b)?a:b;}
    function gen_gain_entry(gain_table)
    {
        str = ""
        for (x=1; x<=num_entry; x++)
        {
            v = min(max(gain_table[x], min_val), max_val)
            str = str sprintf("entry(%d,%.1f)", x-1, v)
            if (x < num_entry) str = str ";"
        }
        return str
    }

    function gen_filter(gain)
    {

        filter=\
        "firequalizer = "\
        "wfunc      = tukey:"\
        "delay      = 0.028:"\
        "scale      = linlog:"\
        "zero_phase = on:"\
        "gain_entry = "quote gain quote":"\
        "gain       = " quote "cubic_interpolate(2.8853900817779269*log(f/157.48+1))" quote
        return filter
    }

    END {
        gain_entry = gen_gain_entry(gain_table)
        gain_filter = gen_filter(gain_entry)
        print gain_filter
    }
  ' /dev/null
}

mpvc_presets()
{
    cmd=${1:-list}
    case "$cmd" in
    reset)      echo "0.0  0.0  0.0  0.0  0.0  0.0  0.0  0.0  0.0  0.0" ;; #preset: flat
    fullbass)   echo "4.8  5.7  5.7  3.3  1.0  -2.4 -4.8 -6.3 -6.7 -6.7";; #preset: fullbass
    fulltreble) echo "5.8  -5.8 -5.8 -2.4 1.4  6.7  9.6  9.6  9.6  10.1";; #preset: fulltreble
    fullbastre) echo "4.3  3.3  0.0  -4.4 -2.9 1.0  4.8  6.7  7.2  7.2" ;; #preset: fullbastre
    headphones) echo "2.8  6.7  3.3  -2.0 -1.4 1.0  2.8  5.7  7.7  8.6" ;; #preset: headphones
    largehall)  echo "6.2  6.2  3.3  3.3  0.0  -2.9 -2.9 -2.9 0.0  0.0" ;; #preset: largehall
    live)       echo "2.9  0.0  2.4  3.3  3.3  3.3  2.4  1.4  1.4  1.4" ;; #preset: live
    party)      echo "4.3  4.3  0.0  0.0  0.0  0.0  0.0  0.0  4.3  4.3" ;; #preset: party
    soft)       echo "2.8  1.0  0.0  -1.4 0.0  2.4  4.8  5.7  6.7  7.2" ;; #preset: soft
    classical)  echo "0.0  0.0  0.0  0.0  0.0  -4.4 -4.4 -4.4 -5.8 0.0" ;; #preset: classical
    club)       echo "0.0  0.0  4.8  3.3  3.3  3.3  1.9  0.0  0.0  0.0" ;; #preset: club
    dance)      echo "5.7  4.3  1.4  0.0  0.0  -3.4 -4.4 -4.3 0.0  0.0" ;; #preset: dance
    pop)        echo "1.0  2.8  4.3  4.8  3.3  0.0  -1.4 -1.4 -1.0 -1.0";; #preset: pop
    reggae)     echo "0.0  0.0  0.0  -3.4 0.0  3.8  3.8  0.0  0.0  0.0" ;; #preset: reggae
    ska)        echo "1.4  -2.9 -2.4 0.0  2.4  3.3  5.3  5.7  6.7  5.8" ;; #preset: ska
    softrock)   echo "2.4  2.4  1.4  0.0  -2.4 -3.4 -2.0 0.0  1.4  5.3" ;; #preset: softrock
    rock)       echo "4.8  2.8  -3.4 -4.8 -2.0 2.4  5.3  6.7  6.7  6.7" ;; #preset: rock
    techno)     echo "4.8  3.3  0.0  -3.4 -2.9 0.0  4.8  5.7  5.8  5.3" ;; #preset: techno

    ''|help|list) awk '/#preset: [a-z]/ { print }' "$0";;
    esac
}


mpvc_values()
{
    mpvc getr af |
        jq '.data | .[] | .params.graph' |
        grep -o "gain_entry = '.*':" |
        sed -n 's/gain_entry = .//; s/.:$//; s|entry([0-9]\{1,2\},\([-.0-9]*\));*|\n\1 |gp' |
        sed '/^$/d'
}

mpvc_setvals()
{
    filter=$(mpvc_genfilter "$*")
    mpvc cmdr af add "@$MPVC_LABEL:lavfi=[$filter]"
}

mpvc_bars()
{
    mpvc_values="$(mpvc_values)"
    if [ -z "$mpvc_values" ]; then usage; fi
    freq_table="$MPVC_FREQ_TABLE"
    gain_table="$(printf "$mpvc_values")"
    pattern=$(echo "$gain_table" | awk 'NR<10{s=s" *"$0} END{sub(" $","",s); print s}')
    preset=$(awk "/$pattern/"' {print $NF}' "$0")
    gain_table=$(echo $gain_table)

    awk -v freq="$freq_table" -v gain="$gain_table" -v cols="$(mpvc ttycols)" -v preset="$preset" '
    function mpvc_bar_line(val)
    {
        valf=val
        min_val=-360
        max_val=770
        inc_val=(max_val - min_val) / cols

        inc=inc_val
        val=valf - min_val
        x=inc

        str=""
        while (x < val)
        {
            str=str"="
            x=x + inc
        }

        return str
    }

    END {
        printf "# Linear Phase 15-Bands Equalizer (%s)\n", preset
        nf=split(freq, fa)
        ng=split(gain, ga)
        for (i=1; i <= 15; i++)
        {
            bar=mpvc_bar_line(ga[i])
            printf "%3s Hz: %6.1f dB %s\n", fa[i], ga[i], bar
        }
    }
    ' /dev/null
}

mpvc_save()
{
    mpvc_vals
}

mpvc_load()
{
    case "${1:-}" in
    '') mpvc_setvals "$(cat)" ;;
    *)  mpvc_setvals "$(mpvc_presets "$1")" ;;
    esac
}

mpvc_reset()  { mpvc_setvals "0 0 0 0 0 0 0 0 0 0 0 0 0 0 0"; }
mpvc_clear()  { mpvc set af ""; }
mpvc_change() { mpvc_setvals $(mpvc_values | sed "$@"); }
mpvc_vals()   { echo "$(mpvc_values)"; }
mpvc_json()   { mpvc getr af | jq -C .data | sed '/graph/ s/:/:\n\t/g'; }

mpvc_add()
{
    mpvc-equalizer save |
        awk -v f="$1" -v g="$2" '
            BEGIN {
                n=split("0  65 157 288 472 733 1k1 1k6 2k4 3k4 4k9 7k0 10k 14k 20k", freq_table)
                for (i=0; i < n; i++) if (freq_table[i] == f) break;
            }
            {
                nr=(i+1)
                if (length($0)) print $0 + ((NR == nr) ? g : 0)
            }
            ' |
            mpvc-equalizer load
}

usage()
{
    echo "usage: $PROGNAME [save|load|reset|clear] # @version $PROGVERSION (c) $PROGAUTHOR $PROGURL"
    exit;
}

main()
{
    if [ $# -lt 1 ]; then usage; fi

    case "$1" in
    save)   shift; mpvc_save "$@";;
    load)   shift; mpvc_load "$@";;
    reset)  shift; mpvc_reset;;
    clear)  shift; mpvc_clear;;
    change) shift; mpvc_change "$@";;
    preset) shift; mpvc_presets "$@";;
    values) shift; mpvc_values;;
    vals)   shift; mpvc_vals;;
    bars)   shift; mpvc_bars;;
    json)   shift; mpvc_json;;

    inc) shift; mpvc_add "$1"  "${2:-0.1}" ;;
    dec) shift; mpvc_add "$1" "-${2:-0.1}" ;;

    help)  usage;;
    *)     usage;;
    esac
}

main "$@"