FIR Filter and Module

constant Coefficients [4] {
        value:  [ 0.25, 0.25, 0.25, 0.25 ]
        meta:   'Coefficients of FIR filter'
}

signal Taps [4] {
        default:        0.0
        rate:           AudioRate
        reset:          MasterReset
        meta:           'Taps holds a single sample Delayed value'
}

AudioIn [1]
>> FixedDelay (
        samples:        [ 0, 1, 2, 3 ]
        default:        0.0
        reset:          off
        bypass:         off
)
>> Taps;

Taps * Coefficients
>> Mix ()
>> AudioOut [1:2];

AudioIn[1] >> FixedDelay ( samples: 0 ) >> Taps[1];
AudioIn[1] >> FixedDelay ( samples: 1 ) >> Taps[2];
AudioIn[1] >> FixedDelay ( samples: 2 ) >> Taps[3];
AudioIn[1] >> FixedDelay ( samples: 3 ) >> Taps[4];

signal Intermediate [4] {
        default:        0.0
        rate:           AudioRate
        reset:          MasterReset
        meta:           'Holds intermediate values of Taps * Coefs'
}

signal Sum {
        default:        0.0
        rate:           AudioRate
        reset:          MasterReset
        meta:           'Holds Sum of Taps * Coefs'
}

Taps[1] * Coefficients[1] >> Intermediate[1];
Taps[2] * Coefficients[2] >> Intermediate[2];
Taps[3] * Coefficients[3] >> Intermediate[3];
Taps[4] * Coefficients[4] >> Intermediate[4];

Intermediate[1] + Intermediate[2] + Intermediate[3] + Intermediate[4] >> Sum;

Sum >> AudioOut[1:2];

module FIR {
        input:                  Input
        output:                 Output
        propertyName:           [ 'length', 'coefficients', 'reset' ]
        propertyDirection:      in
        propertyBlock:  [
                constant Length { value: 2 },
                constant Coefficients [Length] { value: [ 0.5, 0.5 ] },
                trigger Reset {}
        ]
        internalBlock:          [
                signal Input {
                        default:        0.0
                        rate:           streamRate
                        reset:          Reset
                },
                signal Output {
                        default:        0.0
                        rate:           streamRate
                        reset:          Reset
                },
                signal DelayValues [Length] {
                        default:        0
                        rate:           none
                        reset:          none
                },
                signal Taps [Length] {
                        default:        0.0
                        rate:           none
                        reset:          Reset
                }
        ]
        streams:                [
                Counter (
                        startValue:     0
                )
                >> Table (
                        size:   Length
                        rate:   Length
                )
                >> DelayValues;
                ,
                Input
                >> FixedDelay (
                        samples:        DelayValues
                        default:        0.0
                        reset:          Reset
                        bypass:         off
                )
                >> Taps;
                ,
                Taps * Coefficients
                >> Mix ()
                >> Output;
        ]
        meta:                   'Generic Real FIR Filter'
}

constant FIR_Length {
        value:  8
        meta:   'Length of FIR Filter'
}

constant FIR_Coef [FIR_Length] {
        value:  1.0 / FIR_Length
        meta:   'FIR Filter Coefficients'
}

AudioIn[1]
>> FIR (
        length:         FIR_Length
        coefficients:   FIR_Coef
        reset:          off
)
>> AudioOut[1:2];