1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package android.media.audiofx;
18
19import android.media.audiofx.AudioEffect;
20import java.util.StringTokenizer;
21
22/**
23 * A sound generated within a room travels in many directions. The listener first hears the direct
24 * sound from the source itself. Later, he or she hears discrete echoes caused by sound bouncing off
25 * nearby walls, the ceiling and the floor. As sound waves arrive after undergoing more and more
26 * reflections, individual reflections become indistinguishable and the listener hears continuous
27 * reverberation that decays over time.
28 * Reverb is vital for modeling a listener's environment. It can be used in music applications
29 * to simulate music being played back in various environments, or in games to immerse the
30 * listener within the game's environment.
31 * The EnvironmentalReverb class allows an application to control each reverb engine property in a
32 * global reverb environment and is more suitable for games. For basic control, more suitable for
33 * music applications, it is recommended to use the
34 * {@link android.media.audiofx.PresetReverb} class.
35 * <p>An application creates a EnvironmentalReverb object to instantiate and control a reverb engine
36 * in the audio framework.
37 * <p>The methods, parameter types and units exposed by the EnvironmentalReverb implementation are
38 * directly mapping those defined by the OpenSL ES 1.0.1 Specification
39 * (http://www.khronos.org/opensles/) for the SLEnvironmentalReverbItf interface.
40 * Please refer to this specification for more details.
41 * <p>The EnvironmentalReverb is an output mix auxiliary effect and should be created on
42 * Audio session 0. In order for a MediaPlayer or AudioTrack to be fed into this effect,
43 * they must be explicitely attached to it and a send level must be specified. Use the effect ID
44 * returned by getId() method to designate this particular effect when attaching it to the
45 * MediaPlayer or AudioTrack.
46 * <p>Creating a reverb on the output mix (audio session 0) requires permission
47 * {@link android.Manifest.permission#MODIFY_AUDIO_SETTINGS}
48 * <p>See {@link android.media.audiofx.AudioEffect} class for more details on controlling
49 * audio effects.
50 */
51
52public class EnvironmentalReverb extends AudioEffect {
53
54    private final static String TAG = "EnvironmentalReverb";
55
56    // These constants must be synchronized with those in
57    // frameworks/base/include/media/EffectEnvironmentalReverbApi.h
58
59    /**
60     * Room level. Parameter ID for OnParameterChangeListener
61     */
62    public static final int PARAM_ROOM_LEVEL = 0;
63    /**
64     * Room HF level. Parameter ID for OnParameterChangeListener
65     */
66    public static final int PARAM_ROOM_HF_LEVEL = 1;
67    /**
68     * Decay time. Parameter ID for OnParameterChangeListener
69     */
70    public static final int PARAM_DECAY_TIME = 2;
71    /**
72     * Decay HF ratio. Parameter ID for
73     * {@link android.media.audiofx.EnvironmentalReverb.OnParameterChangeListener}
74     */
75    public static final int PARAM_DECAY_HF_RATIO = 3;
76    /**
77     * Early reflections level. Parameter ID for OnParameterChangeListener
78     */
79    public static final int PARAM_REFLECTIONS_LEVEL = 4;
80    /**
81     * Early reflections delay. Parameter ID for OnParameterChangeListener
82     */
83    public static final int PARAM_REFLECTIONS_DELAY = 5;
84    /**
85     * Reverb level. Parameter ID for OnParameterChangeListener
86     */
87    public static final int PARAM_REVERB_LEVEL = 6;
88    /**
89     * Reverb delay. Parameter ID for OnParameterChangeListener
90     */
91    public static final int PARAM_REVERB_DELAY = 7;
92    /**
93     * Diffusion. Parameter ID for OnParameterChangeListener
94     */
95    public static final int PARAM_DIFFUSION = 8;
96    /**
97     * Density. Parameter ID for OnParameterChangeListener
98     */
99    public static final int PARAM_DENSITY = 9;
100
101    // used by setProperties()/getProperties
102    private static final int PARAM_PROPERTIES = 10;
103
104    /**
105     * Registered listener for parameter changes
106     */
107    private OnParameterChangeListener mParamListener = null;
108
109    /**
110     * Listener used internally to to receive raw parameter change event from AudioEffect super
111     * class
112     */
113    private BaseParameterListener mBaseParamListener = null;
114
115    /**
116     * Lock for access to mParamListener
117     */
118    private final Object mParamListenerLock = new Object();
119
120    /**
121     * Class constructor.
122     * @param priority the priority level requested by the application for controlling the
123     * EnvironmentalReverb engine. As the same engine can be shared by several applications, this
124     * parameter indicates how much the requesting application needs control of effect parameters.
125     * The normal priority is 0, above normal is a positive number, below normal a negative number.
126     * @param audioSession  system wide unique audio session identifier. If audioSession
127     *  is not 0, the EnvironmentalReverb will be attached to the MediaPlayer or AudioTrack in the
128     *  same audio session. Otherwise, the EnvironmentalReverb will apply to the output mix.
129     *  As the EnvironmentalReverb is an auxiliary effect it is recommended to instantiate it on
130     *  audio session 0 and to attach it to the MediaPLayer auxiliary output.
131     *
132     * @throws java.lang.IllegalArgumentException
133     * @throws java.lang.UnsupportedOperationException
134     * @throws java.lang.RuntimeException
135     */
136    public EnvironmentalReverb(int priority, int audioSession)
137    throws IllegalArgumentException, UnsupportedOperationException, RuntimeException {
138        super(EFFECT_TYPE_ENV_REVERB, EFFECT_TYPE_NULL, priority, audioSession);
139    }
140
141    /**
142     * Sets the master volume level of the environmental reverb effect.
143     * @param room room level in millibels. The valid range is [-9000, 0].
144     * @throws IllegalStateException
145     * @throws IllegalArgumentException
146     * @throws UnsupportedOperationException
147     */
148    public void setRoomLevel(short room)
149    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
150        byte[] param = shortToByteArray(room);
151        checkStatus(setParameter(PARAM_ROOM_LEVEL, param));
152    }
153
154    /**
155     * Gets the master volume level of the environmental reverb effect.
156     * @return the room level in millibels.
157     * @throws IllegalStateException
158     * @throws IllegalArgumentException
159     * @throws UnsupportedOperationException
160     */
161    public short getRoomLevel()
162    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
163        byte[] param = new byte[2];
164        checkStatus(getParameter(PARAM_ROOM_LEVEL, param));
165        return byteArrayToShort(param);
166    }
167
168    /**
169     * Sets the volume level at 5 kHz relative to the volume level at low frequencies of the
170     * overall reverb effect.
171     * <p>This controls a low-pass filter that will reduce the level of the high-frequency.
172     * @param roomHF high frequency attenuation level in millibels. The valid range is [-9000, 0].
173     * @throws IllegalStateException
174     * @throws IllegalArgumentException
175     * @throws UnsupportedOperationException
176     */
177    public void setRoomHFLevel(short roomHF)
178    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
179        byte[] param = shortToByteArray(roomHF);
180        checkStatus(setParameter(PARAM_ROOM_HF_LEVEL, param));
181    }
182
183    /**
184     * Gets the room HF level.
185     * @return the room HF level in millibels.
186     * @throws IllegalStateException
187     * @throws IllegalArgumentException
188     * @throws UnsupportedOperationException
189     */
190    public short getRoomHFLevel()
191    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
192        byte[] param = new byte[2];
193        checkStatus(getParameter(PARAM_ROOM_HF_LEVEL, param));
194        return byteArrayToShort(param);
195    }
196
197    /**
198     * Sets the time taken for the level of reverberation to decay by 60 dB.
199     * @param decayTime decay time in milliseconds. The valid range is [100, 20000].
200     * @throws IllegalStateException
201     * @throws IllegalArgumentException
202     * @throws UnsupportedOperationException
203     */
204    public void setDecayTime(int decayTime)
205    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
206        byte[] param = intToByteArray(decayTime);
207        checkStatus(setParameter(PARAM_DECAY_TIME, param));
208    }
209
210    /**
211     * Gets the decay time.
212     * @return the decay time in milliseconds.
213     * @throws IllegalStateException
214     * @throws IllegalArgumentException
215     * @throws UnsupportedOperationException
216     */
217    public int getDecayTime()
218    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
219        byte[] param = new byte[4];
220        checkStatus(getParameter(PARAM_DECAY_TIME, param));
221        return byteArrayToInt(param);
222    }
223
224    /**
225     * Sets the ratio of high frequency decay time (at 5 kHz) relative to the decay time at low
226     * frequencies.
227     * @param decayHFRatio high frequency decay ratio using a permille scale. The valid range is
228     * [100, 2000]. A ratio of 1000 indicates that all frequencies decay at the same rate.
229     * @throws IllegalStateException
230     * @throws IllegalArgumentException
231     * @throws UnsupportedOperationException
232     */
233    public void setDecayHFRatio(short decayHFRatio)
234    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
235        byte[] param = shortToByteArray(decayHFRatio);
236        checkStatus(setParameter(PARAM_DECAY_HF_RATIO, param));
237    }
238
239    /**
240     * Gets the ratio of high frequency decay time (at 5 kHz) relative to low frequencies.
241     * @return the decay HF ration. See {@link #setDecayHFRatio(short)} for units.
242     * @throws IllegalStateException
243     * @throws IllegalArgumentException
244     * @throws UnsupportedOperationException
245     */
246    public short getDecayHFRatio()
247    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
248        byte[] param = new byte[2];
249        checkStatus(getParameter(PARAM_DECAY_HF_RATIO, param));
250        return byteArrayToShort(param);
251    }
252
253    /**
254     * Sets the volume level of the early reflections.
255     * <p>This level is combined with the overall room level
256     * (set using {@link #setRoomLevel(short)}).
257     * @param reflectionsLevel reflection level in millibels. The valid range is [-9000, 1000].
258     * @throws IllegalStateException
259     * @throws IllegalArgumentException
260     * @throws UnsupportedOperationException
261     */
262    public void setReflectionsLevel(short reflectionsLevel)
263    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
264        byte[] param = shortToByteArray(reflectionsLevel);
265        checkStatus(setParameter(PARAM_REFLECTIONS_LEVEL, param));
266    }
267
268    /**
269     * Gets the volume level of the early reflections.
270     * @return the early reflections level in millibels.
271     * @throws IllegalStateException
272     * @throws IllegalArgumentException
273     * @throws UnsupportedOperationException
274     */
275    public short getReflectionsLevel()
276    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
277        byte[] param = new byte[2];
278        checkStatus(getParameter(PARAM_REFLECTIONS_LEVEL, param));
279        return byteArrayToShort(param);
280    }
281
282    /**
283     * Sets the delay time for the early reflections.
284     * <p>This method sets the time between when the direct path is heard and when the first
285     * reflection is heard.
286     * @param reflectionsDelay reflections delay in milliseconds. The valid range is [0, 300].
287     * @throws IllegalStateException
288     * @throws IllegalArgumentException
289     * @throws UnsupportedOperationException
290     */
291    public void setReflectionsDelay(int reflectionsDelay)
292    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
293        byte[] param = intToByteArray(reflectionsDelay);
294        checkStatus(setParameter(PARAM_REFLECTIONS_DELAY, param));
295    }
296
297    /**
298     * Gets the reflections delay.
299     * @return the early reflections delay in milliseconds.
300     * @throws IllegalStateException
301     * @throws IllegalArgumentException
302     * @throws UnsupportedOperationException
303     */
304    public int getReflectionsDelay()
305    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
306        byte[] param = new byte[4];
307        checkStatus(getParameter(PARAM_REFLECTIONS_DELAY, param));
308        return byteArrayToInt(param);
309    }
310
311    /**
312     * Sets the volume level of the late reverberation.
313     * <p>This level is combined with the overall room level (set using {@link #setRoomLevel(short)}).
314     * @param reverbLevel reverb level in millibels. The valid range is [-9000, 2000].
315     * @throws IllegalStateException
316     * @throws IllegalArgumentException
317     * @throws UnsupportedOperationException
318     */
319    public void setReverbLevel(short reverbLevel)
320    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
321        byte[] param = shortToByteArray(reverbLevel);
322        checkStatus(setParameter(PARAM_REVERB_LEVEL, param));
323    }
324
325    /**
326     * Gets the reverb level.
327     * @return the reverb level in millibels.
328     * @throws IllegalStateException
329     * @throws IllegalArgumentException
330     * @throws UnsupportedOperationException
331     */
332    public short getReverbLevel()
333    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
334        byte[] param = new byte[2];
335        checkStatus(getParameter(PARAM_REVERB_LEVEL, param));
336        return byteArrayToShort(param);
337    }
338
339    /**
340     * Sets the time between the first reflection and the reverberation.
341     * @param reverbDelay reverb delay in milliseconds. The valid range is [0, 100].
342     * @throws IllegalStateException
343     * @throws IllegalArgumentException
344     * @throws UnsupportedOperationException
345     */
346    public void setReverbDelay(int reverbDelay)
347    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
348        byte[] param = intToByteArray(reverbDelay);
349        checkStatus(setParameter(PARAM_REVERB_DELAY, param));
350    }
351
352    /**
353     * Gets the reverb delay.
354     * @return the reverb delay in milliseconds.
355     * @throws IllegalStateException
356     * @throws IllegalArgumentException
357     * @throws UnsupportedOperationException
358     */
359    public int getReverbDelay()
360    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
361        byte[] param = new byte[4];
362        checkStatus(getParameter(PARAM_REVERB_DELAY, param));
363        return byteArrayToInt(param);
364    }
365
366    /**
367     * Sets the echo density in the late reverberation decay.
368     * <p>The scale should approximately map linearly to the perceived change in reverberation.
369     * @param diffusion diffusion specified using a permille scale. The diffusion valid range is
370     * [0, 1000]. A value of 1000 o/oo indicates a smooth reverberation decay.
371     * Values below this level give a more <i>grainy</i> character.
372     * @throws IllegalStateException
373     * @throws IllegalArgumentException
374     * @throws UnsupportedOperationException
375     */
376    public void setDiffusion(short diffusion)
377    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
378        byte[] param = shortToByteArray(diffusion);
379        checkStatus(setParameter(PARAM_DIFFUSION, param));
380    }
381
382    /**
383     * Gets diffusion level.
384     * @return the diffusion level. See {@link #setDiffusion(short)} for units.
385     * @throws IllegalStateException
386     * @throws IllegalArgumentException
387     * @throws UnsupportedOperationException
388     */
389    public short getDiffusion()
390    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
391        byte[] param = new byte[2];
392        checkStatus(getParameter(PARAM_DIFFUSION, param));
393        return byteArrayToShort(param);
394    }
395
396
397    /**
398     * Controls the modal density of the late reverberation decay.
399     * <p> The scale should approximately map linearly to the perceived change in reverberation.
400     * A lower density creates a hollow sound that is useful for simulating small reverberation
401     * spaces such as bathrooms.
402     * @param density density specified using a permille scale. The valid range is [0, 1000].
403     * A value of 1000 o/oo indicates a natural sounding reverberation. Values below this level
404     * produce a more colored effect.
405     * @throws IllegalStateException
406     * @throws IllegalArgumentException
407     * @throws UnsupportedOperationException
408     */
409    public void setDensity(short density)
410    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
411        byte[] param = shortToByteArray(density);
412        checkStatus(setParameter(PARAM_DENSITY, param));
413    }
414
415    /**
416     * Gets the density level.
417     * @return the density level. See {@link #setDiffusion(short)} for units.
418     * @throws IllegalStateException
419     * @throws IllegalArgumentException
420     * @throws UnsupportedOperationException
421     */
422    public short getDensity()
423    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
424        byte[] param = new byte[2];
425        checkStatus(getParameter(PARAM_DENSITY, param));
426        return byteArrayToShort(param);
427    }
428
429
430    /**
431     * The OnParameterChangeListener interface defines a method called by the EnvironmentalReverb
432     * when a parameter value has changed.
433     */
434    public interface OnParameterChangeListener  {
435        /**
436         * Method called when a parameter value has changed. The method is called only if the
437         * parameter was changed by another application having the control of the same
438         * EnvironmentalReverb engine.
439         * @param effect the EnvironmentalReverb on which the interface is registered.
440         * @param status status of the set parameter operation.
441         * @param param ID of the modified parameter. See {@link #PARAM_ROOM_LEVEL} ...
442         * @param value the new parameter value.
443         */
444        void onParameterChange(EnvironmentalReverb effect, int status, int param, int value);
445    }
446
447    /**
448     * Listener used internally to receive unformatted parameter change events from AudioEffect
449     * super class.
450     */
451    private class BaseParameterListener implements AudioEffect.OnParameterChangeListener {
452        private BaseParameterListener() {
453
454        }
455        public void onParameterChange(AudioEffect effect, int status, byte[] param, byte[] value) {
456            OnParameterChangeListener l = null;
457
458            synchronized (mParamListenerLock) {
459                if (mParamListener != null) {
460                    l = mParamListener;
461                }
462            }
463            if (l != null) {
464                int p = -1;
465                int v = -1;
466
467                if (param.length == 4) {
468                    p = byteArrayToInt(param, 0);
469                }
470                if (value.length == 2) {
471                    v = (int)byteArrayToShort(value, 0);
472                } else if (value.length == 4) {
473                    v = byteArrayToInt(value, 0);
474                }
475                if (p != -1 && v != -1) {
476                    l.onParameterChange(EnvironmentalReverb.this, status, p, v);
477                }
478            }
479        }
480    }
481
482    /**
483     * Registers an OnParameterChangeListener interface.
484     * @param listener OnParameterChangeListener interface registered
485     */
486    public void setParameterListener(OnParameterChangeListener listener) {
487        synchronized (mParamListenerLock) {
488            if (mParamListener == null) {
489                mParamListener = listener;
490                mBaseParamListener = new BaseParameterListener();
491                super.setParameterListener(mBaseParamListener);
492            }
493        }
494    }
495
496    /**
497     * The Settings class regroups all environmental reverb parameters. It is used in
498     * conjuntion with getProperties() and setProperties() methods to backup and restore
499     * all parameters in a single call.
500     */
501    public static class Settings {
502        public short roomLevel;
503        public short roomHFLevel;
504        public int decayTime;
505        public short decayHFRatio;
506        public short reflectionsLevel;
507        public int reflectionsDelay;
508        public short reverbLevel;
509        public int reverbDelay;
510        public short diffusion;
511        public short density;
512
513        public Settings() {
514        }
515
516        /**
517         * Settings class constructor from a key=value; pairs formatted string. The string is
518         * typically returned by Settings.toString() method.
519         * @throws IllegalArgumentException if the string is not correctly formatted.
520         */
521        public Settings(String settings) {
522            StringTokenizer st = new StringTokenizer(settings, "=;");
523            int tokens = st.countTokens();
524            if (st.countTokens() != 21) {
525                throw new IllegalArgumentException("settings: " + settings);
526            }
527            String key = st.nextToken();
528            if (!key.equals("EnvironmentalReverb")) {
529                throw new IllegalArgumentException(
530                        "invalid settings for EnvironmentalReverb: " + key);
531            }
532
533            try {
534                key = st.nextToken();
535                if (!key.equals("roomLevel")) {
536                    throw new IllegalArgumentException("invalid key name: " + key);
537                }
538                roomLevel = Short.parseShort(st.nextToken());
539                key = st.nextToken();
540                if (!key.equals("roomHFLevel")) {
541                    throw new IllegalArgumentException("invalid key name: " + key);
542                }
543                roomHFLevel = Short.parseShort(st.nextToken());
544                key = st.nextToken();
545                if (!key.equals("decayTime")) {
546                    throw new IllegalArgumentException("invalid key name: " + key);
547                }
548                decayTime = Integer.parseInt(st.nextToken());
549                key = st.nextToken();
550                if (!key.equals("decayHFRatio")) {
551                    throw new IllegalArgumentException("invalid key name: " + key);
552                }
553                decayHFRatio = Short.parseShort(st.nextToken());
554                key = st.nextToken();
555                if (!key.equals("reflectionsLevel")) {
556                    throw new IllegalArgumentException("invalid key name: " + key);
557                }
558                reflectionsLevel = Short.parseShort(st.nextToken());
559                key = st.nextToken();
560                if (!key.equals("reflectionsDelay")) {
561                    throw new IllegalArgumentException("invalid key name: " + key);
562                }
563                reflectionsDelay = Integer.parseInt(st.nextToken());
564                key = st.nextToken();
565                if (!key.equals("reverbLevel")) {
566                    throw new IllegalArgumentException("invalid key name: " + key);
567                }
568                reverbLevel = Short.parseShort(st.nextToken());
569                key = st.nextToken();
570                if (!key.equals("reverbDelay")) {
571                    throw new IllegalArgumentException("invalid key name: " + key);
572                }
573                reverbDelay = Integer.parseInt(st.nextToken());
574                key = st.nextToken();
575                if (!key.equals("diffusion")) {
576                    throw new IllegalArgumentException("invalid key name: " + key);
577                }
578                diffusion = Short.parseShort(st.nextToken());
579                key = st.nextToken();
580                if (!key.equals("density")) {
581                    throw new IllegalArgumentException("invalid key name: " + key);
582                }
583                density = Short.parseShort(st.nextToken());
584             } catch (NumberFormatException nfe) {
585                throw new IllegalArgumentException("invalid value for key: " + key);
586            }
587        }
588
589        @Override
590        public String toString() {
591            return new String (
592                    "EnvironmentalReverb"+
593                    ";roomLevel="+Short.toString(roomLevel)+
594                    ";roomHFLevel="+Short.toString(roomHFLevel)+
595                    ";decayTime="+Integer.toString(decayTime)+
596                    ";decayHFRatio="+Short.toString(decayHFRatio)+
597                    ";reflectionsLevel="+Short.toString(reflectionsLevel)+
598                    ";reflectionsDelay="+Integer.toString(reflectionsDelay)+
599                    ";reverbLevel="+Short.toString(reverbLevel)+
600                    ";reverbDelay="+Integer.toString(reverbDelay)+
601                    ";diffusion="+Short.toString(diffusion)+
602                    ";density="+Short.toString(density)
603                    );
604        }
605    };
606
607    // Keep this in sync with sizeof(s_reverb_settings) defined in
608    // frameworks/base/include/media/EffectEnvironmentalReverbApi.h
609    static private int PROPERTY_SIZE = 26;
610
611    /**
612     * Gets the environmental reverb properties. This method is useful when a snapshot of current
613     * reverb settings must be saved by the application.
614     * @return an EnvironmentalReverb.Settings object containing all current parameters values
615     * @throws IllegalStateException
616     * @throws IllegalArgumentException
617     * @throws UnsupportedOperationException
618     */
619    public EnvironmentalReverb.Settings getProperties()
620    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
621        byte[] param = new byte[PROPERTY_SIZE];
622        checkStatus(getParameter(PARAM_PROPERTIES, param));
623        Settings settings = new Settings();
624        settings.roomLevel = byteArrayToShort(param, 0);
625        settings.roomHFLevel = byteArrayToShort(param, 2);
626        settings.decayTime = byteArrayToInt(param, 4);
627        settings.decayHFRatio = byteArrayToShort(param, 8);
628        settings.reflectionsLevel = byteArrayToShort(param, 10);
629        settings.reflectionsDelay = byteArrayToInt(param, 12);
630        settings.reverbLevel = byteArrayToShort(param, 16);
631        settings.reverbDelay = byteArrayToInt(param, 18);
632        settings.diffusion = byteArrayToShort(param, 22);
633        settings.density = byteArrayToShort(param, 24);
634        return settings;
635    }
636
637    /**
638     * Sets the environmental reverb properties. This method is useful when reverb settings have to
639     * be applied from a previous backup.
640     * @param settings a EnvironmentalReverb.Settings object containing the properties to apply
641     * @throws IllegalStateException
642     * @throws IllegalArgumentException
643     * @throws UnsupportedOperationException
644     */
645    public void setProperties(EnvironmentalReverb.Settings settings)
646    throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException {
647
648        byte[] param = concatArrays(shortToByteArray(settings.roomLevel),
649                                    shortToByteArray(settings.roomHFLevel),
650                                    intToByteArray(settings.decayTime),
651                                    shortToByteArray(settings.decayHFRatio),
652                                    shortToByteArray(settings.reflectionsLevel),
653                                    intToByteArray(settings.reflectionsDelay),
654                                    shortToByteArray(settings.reverbLevel),
655                                    intToByteArray(settings.reverbDelay),
656                                    shortToByteArray(settings.diffusion),
657                                    shortToByteArray(settings.density));
658
659        checkStatus(setParameter(PARAM_PROPERTIES, param));
660    }
661}
662