Nsound::ReverberationRoom Class Reference

#include <Nsound/ReverberationRoom.h>

Public Member Functions
	ReverberationRoom (const float64 &sample_rate, const float64 &room_feedback, const float64 &wet_percent=0.5, const float64 &dry_percent=1.0, const float64 &low_pass_frequency_Hz=7644.9, const float64 &stereo_spread_seconds=0.0005215)
	Default Constructor. More...
	ReverberationRoom (const ReverberationRoom &copy)
virtual	~ReverberationRoom ()
AudioStream	filter (const AudioStream &x)
AudioStream	filter (const Buffer &x)
void	filter (float64 &out_left, float64 &out_right, const float64 &in_left, const float64 &in_right)
float64	getSampleRate () const
ReverberationRoom &	operator= (const ReverberationRoom &rhs)
void	reset ()

Protected Attributes
float64	sample_rate_
float64	wet_percent_
float64	dry_percent_
FilterCombLowPassFeedback **	comb_left_
FilterCombLowPassFeedback **	comb_right_
FilterAllPass **	allpass_left_
FilterAllPass **	allpass_right_

Static Protected Attributes
static const float64	ROOM_FEEDBACK_SCALE_ = 0.28
static const float64	ROOM_FEEDBACK_OFFSET_ = 0.7
static const uint32	N_COMB_FILTERS_ = 8
static const uint32	N_ALL_PASS_FILTERS_ = 4
static const float64	COMB_DELAY_TIME_SECONDS_ [N_COMB_FILTERS_]
static const float64	ALL_PASS_DELAY_TIME_SECONDS_ [N_ALL_PASS_FILTERS_]

Detailed Description

Definition at line 49 of file ReverberationRoom.h.

Constructor & Destructor Documentation

ReverberationRoom::ReverberationRoom	(	const float64 &	sample_rate,
		const float64 &	room_feedback,
		const float64 &	wet_percent = 0.5,
		const float64 &	dry_percent = 1.0,
		const float64 &	low_pass_frequency_Hz = 7644.9,
		const float64 &	stereo_spread_seconds = 0.0005215
	)

Default Constructor.

sample_rate: the sample rate room_feedback: 0.0 to 1.0, how quickly the room dampens the input wet_percent: 0.0 to 1.0, how much of the filtered input is added to the output dry_percent: 0.0 to 1.0, how much of the original input is added to the output low_pass_frequency_Hz: 0.0 to 1/2 sample rate, attenuate frequencies in the feedback stereo_spread_seconds: >= 0.0, how much delay between the Left and Right channels

Definition at line 91 of file ReverberationRoom.cc.

References ALL_PASS_DELAY_TIME_SECONDS_, allpass_left_, allpass_right_, COMB_DELAY_TIME_SECONDS_, comb_left_, comb_right_, dry_percent_, N_ALL_PASS_FILTERS_, N_COMB_FILTERS_, reset(), ROOM_FEEDBACK_OFFSET_, ROOM_FEEDBACK_SCALE_, sample_rate_, and wet_percent_.

    :
    sample_rate_(sample_rate),
    wet_percent_(wet_percent),
    dry_percent_(dry_percent),
    comb_left_(NULL),
    comb_right_(NULL),
    allpass_left_(NULL),
    allpass_right_(NULL)
{
    // Bounds checks:
    if(wet_percent_ < 0.0)
    {
        wet_percent_ = 0.0;
    }

    if(wet_percent_ > 1.0)
    {
        wet_percent_ = 1.0;
    }

    if(dry_percent_ < 0.0)
    {
        dry_percent_ = 0.0;
    }

    if(dry_percent_ > 1.0)
    {
        dry_percent_ = 1.0;
    }

    float64 lpf = low_pass_frequency_Hz;

    if(lpf < 0.0)
    {
        lpf = 0.0;
    }

    float64 stereo_spread = stereo_spread_seconds;

    if(stereo_spread < 0.0)
    {
        stereo_spread = 0.0;
    }

    // Convert the room size to a delay time.
    float64 comb_feedback = ROOM_FEEDBACK_SCALE_ * room_feedback
                          + ROOM_FEEDBACK_OFFSET_;

    // Allocate filter pointers
    comb_left_  = new FilterCombLowPassFeedback * [N_COMB_FILTERS_];
    comb_right_ = new FilterCombLowPassFeedback * [N_COMB_FILTERS_];

    for(uint32 i = 0; i < N_COMB_FILTERS_; ++i)
    {
        comb_left_[i] = new FilterCombLowPassFeedback(
            sample_rate_,
            COMB_DELAY_TIME_SECONDS_[i],
            comb_feedback,
            lpf);

        comb_right_[i] = new FilterCombLowPassFeedback(
            sample_rate_,
            COMB_DELAY_TIME_SECONDS_[i] + stereo_spread,
            comb_feedback,
            lpf);
    }

    // Allocate filter pointers
    allpass_left_  = new FilterAllPass * [N_ALL_PASS_FILTERS_];
    allpass_right_ = new FilterAllPass * [N_ALL_PASS_FILTERS_];

    for(uint32 i = 0; i < N_ALL_PASS_FILTERS_; ++i)
    {
        allpass_left_[i] = new FilterAllPass(
            sample_rate_,
            ALL_PASS_DELAY_TIME_SECONDS_[i],
            0.5);

        allpass_right_[i] = new FilterAllPass(
            sample_rate_,
            ALL_PASS_DELAY_TIME_SECONDS_[i] + stereo_spread,
            0.5);
    }

    ReverberationRoom::reset();

    // Init random number generator.
    std::srand(static_cast<unsigned int>(std::time(0)));
}

ReverberationRoom::ReverberationRoom

(

const ReverberationRoom &

copy

)

Definition at line 190 of file ReverberationRoom.cc.

    :
    sample_rate_(copy.sample_rate_),
    wet_percent_(copy.wet_percent_),
    dry_percent_(copy.dry_percent_),
    comb_left_(NULL),
    comb_right_(NULL),
    allpass_left_(NULL),
    allpass_right_(NULL)
{
    *this = copy;
}

ReverberationRoom::~ReverberationRoom ( )

virtual

Definition at line 205 of file ReverberationRoom.cc.

References allpass_left_, allpass_right_, comb_left_, comb_right_, N_ALL_PASS_FILTERS_, and N_COMB_FILTERS_.

{
    for(uint32 i = 0; i < N_COMB_FILTERS_; ++i)
    {
        delete comb_left_[i];
        delete comb_right_[i];
    }
    delete [] comb_left_;
    delete [] comb_right_;

    for(uint32 i = 0; i < N_ALL_PASS_FILTERS_; ++i)
    {
        delete allpass_left_[i];
        delete allpass_right_[i];
    }
    delete [] allpass_left_;
    delete [] allpass_right_;
}

Member Function Documentation

AudioStream ReverberationRoom::filter

(

const AudioStream &

x

)

Definition at line 226 of file ReverberationRoom.cc.

References Nsound::AudioStream::getLength(), Nsound::AudioStream::getNChannels(), reset(), and sample_rate_.

Referenced by filter(), main(), and my_main().

{
    if(x.getNChannels() == 1)
    {
        return filter(x[0]);
    }
    else if(x.getNChannels() < 2)
    {
        return x;
    }

    reset();

    AudioStream y(sample_rate_, 2);

    uint32 n_samples = x.getLength();

    float64 left;
    float64 right;

    for(uint32 n = 0; n < n_samples; ++n)
    {
        filter(left, right, x[0][n], x[1][n]);

        y[0] << left;
        y[1] << right;
    }

    return y;
}

AudioStream ReverberationRoom::filter

(

const Buffer &

x

)

Definition at line 259 of file ReverberationRoom.cc.

References filter(), Nsound::Buffer::getLength(), reset(), and sample_rate_.

{
    reset();
    AudioStream y(sample_rate_, 2);

    uint32 n_samples = x.getLength();

    float64 left;
    float64 right;

    for(uint32 n = 0; n < n_samples; ++n)
    {
        filter(left, right, x[n], x[n]);

        y[0] << left;
        y[1] << right;
    }

    return y;
}

void ReverberationRoom::filter	(	float64 &	out_left,
		float64 &	out_right,
		const float64 &	in_left,
		const float64 &	in_right
	)

Definition at line 282 of file ReverberationRoom.cc.

References allpass_left_, allpass_right_, comb_left_, comb_right_, dry_percent_, Nsound::FilterAllPass::filter(), Nsound::FilterCombLowPassFeedback::filter(), getRandom(), N_ALL_PASS_FILTERS_, N_COMB_FILTERS_, and wet_percent_.

{
    out_left  = 0.0 + getRandom() * 1e-23;
    out_right = 0.0 + getRandom() * 1e-23;

    // Sum the comb filters in parallel
    for(uint32 i = 0; i < N_COMB_FILTERS_; ++i)
    {
        out_left  += comb_left_[i]->filter(in_left * 0.15);
        out_right += comb_right_[i]->filter(in_right * 0.15);
    }

    // Serilalize the all pass fitlers
    for(uint32 i = 0; i < N_ALL_PASS_FILTERS_; ++i)
    {
        out_left  = allpass_left_[i]->filter(out_left);
        out_right = allpass_right_[i]->filter(out_left);
    }

    out_left  =  wet_percent_ * out_left  + dry_percent_ * in_left;
    out_right =  wet_percent_ * out_right + dry_percent_ * in_right;
}

float64 Nsound::ReverberationRoom::getSampleRate ( ) const

inline

Definition at line 88 of file ReverberationRoom.h.

References sample_rate_.

{ return sample_rate_; };

ReverberationRoom & ReverberationRoom::operator=

(

const ReverberationRoom &

rhs

)

Definition at line 312 of file ReverberationRoom.cc.

References allpass_left_, allpass_right_, comb_left_, comb_right_, dry_percent_, N_ALL_PASS_FILTERS_, N_COMB_FILTERS_, sample_rate_, and wet_percent_.

{
    if(this == & rhs)
    {
        return *this;
    }

    sample_rate_ = rhs.sample_rate_;
    wet_percent_ = rhs.wet_percent_;
    dry_percent_ = rhs.dry_percent_;

    for(uint32 i = 0; i < N_COMB_FILTERS_; ++i)
    {
        *comb_left_[i] = *(rhs.comb_left_[i]);
        *comb_right_[i] = *(rhs.comb_right_[i]);
    }

    for(uint32 i = 0; i < N_ALL_PASS_FILTERS_; ++i)
    {
        *allpass_left_[i] = *(rhs.allpass_left_[i]);
        *allpass_right_[i] = *(rhs.allpass_right_[i]);
    }

    return *this;
}

void ReverberationRoom::reset

(

)

Definition at line 340 of file ReverberationRoom.cc.

References allpass_left_, allpass_right_, comb_left_, comb_right_, N_ALL_PASS_FILTERS_, N_COMB_FILTERS_, Nsound::FilterCombLowPassFeedback::reset(), and Nsound::FilterAllPass::reset().

Referenced by filter(), and ReverberationRoom().

{
     for(uint32 i = 0; i < N_COMB_FILTERS_; ++i)
    {
        comb_left_[i]->reset();
        comb_right_[i]->reset();
    }

    for(uint32 i = 0; i < N_ALL_PASS_FILTERS_; ++i)
    {
        allpass_left_[i]->reset();
        allpass_right_[i]->reset();
    }
}

Member Data Documentation

float64 Nsound::ReverberationRoom::sample_rate_

protected

Definition at line 98 of file ReverberationRoom.h.

Referenced by filter(), getSampleRate(), operator=(), and ReverberationRoom().

float64 Nsound::ReverberationRoom::wet_percent_

protected

Definition at line 100 of file ReverberationRoom.h.

Referenced by filter(), operator=(), and ReverberationRoom().

float64 Nsound::ReverberationRoom::dry_percent_

protected

Definition at line 101 of file ReverberationRoom.h.

Referenced by filter(), operator=(), and ReverberationRoom().

FilterCombLowPassFeedback** Nsound::ReverberationRoom::comb_left_

protected

Definition at line 103 of file ReverberationRoom.h.

Referenced by filter(), operator=(), reset(), ReverberationRoom(), and ~ReverberationRoom().

FilterCombLowPassFeedback** Nsound::ReverberationRoom::comb_right_

protected

Definition at line 104 of file ReverberationRoom.h.

Referenced by filter(), operator=(), reset(), ReverberationRoom(), and ~ReverberationRoom().

FilterAllPass** Nsound::ReverberationRoom::allpass_left_

protected

Definition at line 106 of file ReverberationRoom.h.

Referenced by filter(), operator=(), reset(), ReverberationRoom(), and ~ReverberationRoom().

FilterAllPass** Nsound::ReverberationRoom::allpass_right_

protected

Definition at line 107 of file ReverberationRoom.h.

Referenced by filter(), operator=(), reset(), ReverberationRoom(), and ~ReverberationRoom().

const float64 ReverberationRoom::ROOM_FEEDBACK_SCALE_ = 0.28

staticprotected

Definition at line 109 of file ReverberationRoom.h.

Referenced by ReverberationRoom().

const float64 ReverberationRoom::ROOM_FEEDBACK_OFFSET_ = 0.7

staticprotected

Definition at line 110 of file ReverberationRoom.h.

Referenced by ReverberationRoom().

const uint32 Nsound::ReverberationRoom::N_COMB_FILTERS_ = 8

staticprotected

Definition at line 112 of file ReverberationRoom.h.

Referenced by filter(), operator=(), reset(), ReverberationRoom(), and ~ReverberationRoom().

const uint32 Nsound::ReverberationRoom::N_ALL_PASS_FILTERS_ = 4

staticprotected

Definition at line 113 of file ReverberationRoom.h.

Referenced by filter(), operator=(), reset(), ReverberationRoom(), and ~ReverberationRoom().

const float64 ReverberationRoom::COMB_DELAY_TIME_SECONDS_

staticprotected

Initial value:

=
{
    1116.0 / 44100.0,
    1188.0 / 44100.0,
    1277.0 / 44100.0,
    1356.0 / 44100.0,
    1422.0 / 44100.0,
    1491.0 / 44100.0,
    1557.0 / 44100.0,
    1617.0 / 44100.0
}

Definition at line 115 of file ReverberationRoom.h.

Referenced by ReverberationRoom().

const float64 ReverberationRoom::ALL_PASS_DELAY_TIME_SECONDS_

staticprotected

Initial value:

=
{
    556.0 / 44100.0,
    441.0 / 44100.0,
    341.0 / 44100.0,
    225.0 / 44100.0
}

Definition at line 117 of file ReverberationRoom.h.

Referenced by ReverberationRoom().

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The documentation for this class was generated from the following files:

• Nsound/ReverberationRoom.h
• Nsound/ReverberationRoom.cc