/*
 * Copyright (c) 1999, 2003, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package javax.sound.sampled;


The ReverbType class provides methods for accessing various reverberation settings to be applied to an audio signal.

Reverberation simulates the reflection of sound off of the walls, ceiling, and floor of a room. Depending on the size of the room, and how absorbent or reflective the materials in the room's surfaces are, the sound might bounce around for a long time before dying away.

The reverberation parameters provided by ReverbType consist of the delay time and intensity of early reflections, the delay time and intensity of late reflections, and an overall decay time. Early reflections are the initial individual low-order reflections of the direct signal off the surfaces in the room. The late Relections are the dense, high-order reflections that characterize the room's reverberation. The delay times for the start of these two reflection types give the listener a sense of the overall size and complexity of the room's shape and contents. The larger the room, the longer the reflection delay times. The early and late reflections' intensities define the gain (in decibels) of the reflected signals as compared to the direct signal. These intensities give the listener an impression of the absorptive nature of the surfaces and objects in the room. The decay time defines how long the reverberation takes to exponentially decay until it is no longer perceptible ("effective zero"). The larger and less absorbent the surfaces, the longer the decay time.

The set of parameters defined here may not include all aspects of reverberation as specified by some systems. For example, the Midi Manufacturer's Association (MMA) has an Interactive Audio Special Interest Group (IASIG), which has a 3-D Working Group that has defined a Level 2 Spec (I3DL2). I3DL2 supports filtering of reverberation and control of reverb density. These properties are not included in the JavaSound 1.0 definition of a reverb control. In such a case, the implementing system should either extend the defined reverb control to include additional parameters, or else interpret the system's additional capabilities in a way that fits the model described here.

If implementing JavaSound on a I3DL2-compliant device:

  • Filtering is disabled (high-frequency attenuations are set to 0.0 dB)
  • Density parameters are set to midway between minimum and maximum

The following table shows what parameter values an implementation might use for a representative set of reverberation settings.

Reverberation Types and Parameters

Type Decay Time (ms) Late Intensity (dB) Late Delay (ms) Early Intensity (dB) Early Delay(ms)
Cavern 2250 -2.0 41.3 -1.4 10.3
Dungeon 1600 -1.0 10.3 -0.7 2.6
Garage 900 -6.0 14.7 -4.0 3.9
Acoustic Lab 280 -3.0 8.0 -2.0 2.0
Closet 150 -10.0 2.5 -7.0 0.6
Author:Kara Kytle
Since:1.3
/** * The <code>ReverbType</code> class provides methods for * accessing various reverberation settings to be applied to * an audio signal. * <p> * Reverberation simulates the reflection of sound off of * the walls, ceiling, and floor of a room. Depending on * the size of the room, and how absorbent or reflective the materials in the * room's surfaces are, the sound might bounce around for a * long time before dying away. * <p> * The reverberation parameters provided by <code>ReverbType</code> consist * of the delay time and intensity of early reflections, the delay time and * intensity of late reflections, and an overall decay time. * Early reflections are the initial individual low-order reflections of the * direct signal off the surfaces in the room. * The late Relections are the dense, high-order reflections that characterize * the room's reverberation. * The delay times for the start of these two reflection types give the listener * a sense of the overall size and complexity of the room's shape and contents. * The larger the room, the longer the reflection delay times. * The early and late reflections' intensities define the gain (in decibels) of the reflected * signals as compared to the direct signal. These intensities give the * listener an impression of the absorptive nature of the surfaces and objects * in the room. * The decay time defines how long the reverberation takes to exponentially * decay until it is no longer perceptible ("effective zero"). * The larger and less absorbent the surfaces, the longer the decay time. * <p> * The set of parameters defined here may not include all aspects of reverberation * as specified by some systems. For example, the Midi Manufacturer's Association * (MMA) has an Interactive Audio Special Interest Group (IASIG), which has a * 3-D Working Group that has defined a Level 2 Spec (I3DL2). I3DL2 * supports filtering of reverberation and * control of reverb density. These properties are not included in the JavaSound 1.0 * definition of a reverb control. In such a case, the implementing system * should either extend the defined reverb control to include additional * parameters, or else interpret the system's additional capabilities in a way that fits * the model described here. * <p> * If implementing JavaSound on a I3DL2-compliant device: * <ul> * <li>Filtering is disabled (high-frequency attenuations are set to 0.0 dB) * <li>Density parameters are set to midway between minimum and maximum * </ul> * <p> * The following table shows what parameter values an implementation might use for a * representative set of reverberation settings. * <p> * * <b>Reverberation Types and Parameters</b> * <p> * <table border=1 cellpadding=5 summary="reverb types and params: decay time, late intensity, late delay, early intensity, and early delay"> * * <tr> * <th>Type</th> * <th>Decay Time (ms)</th> * <th>Late Intensity (dB)</th> * <th>Late Delay (ms)</th> * <th>Early Intensity (dB)</th> * <th>Early Delay(ms)</th> * </tr> * * <tr> * <td>Cavern</td> * <td>2250</td> * <td>-2.0</td> * <td>41.3</td> * <td>-1.4</td> * <td>10.3</td> * </tr> * * <tr> * <td>Dungeon</td> * <td>1600</td> * <td>-1.0</td> * <td>10.3</td> * <td>-0.7</td> * <td>2.6</td> * </tr> * * <tr> * <td>Garage</td> * <td>900</td> * <td>-6.0</td> * <td>14.7</td> * <td>-4.0</td> * <td>3.9</td> * </tr> * * <tr> * <td>Acoustic Lab</td> * <td>280</td> * <td>-3.0</td> * <td>8.0</td> * <td>-2.0</td> * <td>2.0</td> * </tr> * * <tr> * <td>Closet</td> * <td>150</td> * <td>-10.0</td> * <td>2.5</td> * <td>-7.0</td> * <td>0.6</td> * </tr> * * </table> * * @author Kara Kytle * @since 1.3 */
public class ReverbType {
Descriptive name of the reverb type..
/** * Descriptive name of the reverb type.. */
private String name;
Early reflection delay in microseconds.
/** * Early reflection delay in microseconds. */
private int earlyReflectionDelay;
Early reflection intensity.
/** * Early reflection intensity. */
private float earlyReflectionIntensity;
Late reflection delay in microseconds.
/** * Late reflection delay in microseconds. */
private int lateReflectionDelay;
Late reflection intensity.
/** * Late reflection intensity. */
private float lateReflectionIntensity;
Total decay time
/** * Total decay time */
private int decayTime;
Constructs a new reverb type that has the specified reverberation parameter values.
Params:
  • name – the name of the new reverb type, or a zero-length String
  • earlyReflectionDelay – the new type's early reflection delay time in microseconds
  • earlyReflectionIntensity – the new type's early reflection intensity in dB
  • lateReflectionDelay – the new type's late reflection delay time in microseconds
  • lateReflectionIntensity – the new type's late reflection intensity in dB
  • decayTime – the new type's decay time in microseconds
/** * Constructs a new reverb type that has the specified reverberation * parameter values. * @param name the name of the new reverb type, or a zero-length <code>String</code> * @param earlyReflectionDelay the new type's early reflection delay time in microseconds * @param earlyReflectionIntensity the new type's early reflection intensity in dB * @param lateReflectionDelay the new type's late reflection delay time in microseconds * @param lateReflectionIntensity the new type's late reflection intensity in dB * @param decayTime the new type's decay time in microseconds */
protected ReverbType(String name, int earlyReflectionDelay, float earlyReflectionIntensity, int lateReflectionDelay, float lateReflectionIntensity, int decayTime) { this.name = name; this.earlyReflectionDelay = earlyReflectionDelay; this.earlyReflectionIntensity = earlyReflectionIntensity; this.lateReflectionDelay = lateReflectionDelay; this.lateReflectionIntensity = lateReflectionIntensity; this.decayTime = decayTime; }
Obtains the name of this reverb type.
Returns:the name of this reverb type
Since:1.5
/** * Obtains the name of this reverb type. * @return the name of this reverb type * @since 1.5 */
public String getName() { return name; }
Returns the early reflection delay time in microseconds. This is the amount of time between when the direct signal is heard and when the first early reflections are heard.
Returns: early reflection delay time for this reverb type, in microseconds
/** * Returns the early reflection delay time in microseconds. * This is the amount of time between when the direct signal is * heard and when the first early reflections are heard. * @return early reflection delay time for this reverb type, in microseconds */
public final int getEarlyReflectionDelay() { return earlyReflectionDelay; }
Returns the early reflection intensity in decibels. This is the amplitude attenuation of the first early reflections relative to the direct signal.
Returns: early reflection intensity for this reverb type, in dB
/** * Returns the early reflection intensity in decibels. * This is the amplitude attenuation of the first early reflections * relative to the direct signal. * @return early reflection intensity for this reverb type, in dB */
public final float getEarlyReflectionIntensity() { return earlyReflectionIntensity; }
Returns the late reflection delay time in microseconds. This is the amount of time between when the first early reflections are heard and when the first late reflections are heard.
Returns: late reflection delay time for this reverb type, in microseconds
/** * Returns the late reflection delay time in microseconds. * This is the amount of time between when the first early reflections * are heard and when the first late reflections are heard. * @return late reflection delay time for this reverb type, in microseconds */
public final int getLateReflectionDelay() { return lateReflectionDelay; }
Returns the late reflection intensity in decibels. This is the amplitude attenuation of the first late reflections relative to the direct signal.
Returns: late reflection intensity for this reverb type, in dB
/** * Returns the late reflection intensity in decibels. * This is the amplitude attenuation of the first late reflections * relative to the direct signal. * @return late reflection intensity for this reverb type, in dB */
public final float getLateReflectionIntensity() { return lateReflectionIntensity; }
Obtains the decay time, which is the amount of time over which the late reflections attenuate to effective zero. The effective zero value is implementation-dependent.
Returns: the decay time of the late reflections, in microseconds
/** * Obtains the decay time, which is the amount of time over which the * late reflections attenuate to effective zero. The effective zero * value is implementation-dependent. * @return the decay time of the late reflections, in microseconds */
public final int getDecayTime() { return decayTime; }
Indicates whether the specified object is equal to this reverb type, returning true if the objects are identical.
Params:
  • obj – the reference object with which to compare
Returns:true if this reverb type is the same as obj; false otherwise
/** * Indicates whether the specified object is equal to this reverb type, * returning <code>true</code> if the objects are identical. * @param obj the reference object with which to compare * @return <code>true</code> if this reverb type is the same as * <code>obj</code>; <code>false</code> otherwise */
public final boolean equals(Object obj) { return super.equals(obj); }
Finalizes the hashcode method.
/** * Finalizes the hashcode method. */
public final int hashCode() { return super.hashCode(); }
Provides a String representation of the reverb type, including its name and its parameter settings. The exact contents of the string may vary between implementations of Java Sound.
Returns:reverberation type name and description
/** * Provides a <code>String</code> representation of the reverb type, * including its name and its parameter settings. * The exact contents of the string may vary between implementations of * Java Sound. * @return reverberation type name and description */
public final String toString() { //$$fb2001-07-20: fix for bug 4385060: The "name" attribute of class "ReverbType" is not accessible. //return (super.toString() + ", early reflection delay " + earlyReflectionDelay + return (name + ", early reflection delay " + earlyReflectionDelay + " ns, early reflection intensity " + earlyReflectionIntensity + " dB, late deflection delay " + lateReflectionDelay + " ns, late reflection intensity " + lateReflectionIntensity + " dB, decay time " + decayTime); } } // class ReverbType