| /* |
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| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
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| * published by the Free Software Foundation. Oracle designates this |
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| |
| package javax.sound.midi; |
| |
| |
| /** |
| * A <code>VoiceStatus</code> object contains information about the current |
| * status of one of the voices produced by a {@link Synthesizer}. |
| * <p> |
| * MIDI synthesizers are generally capable of producing some maximum number of |
| * simultaneous notes, also referred to as voices. A voice is a stream |
| * of successive single notes, and the process of assigning incoming MIDI notes to |
| * specific voices is known as voice allocation. |
| * However, the voice-allocation algorithm and the contents of each voice are |
| * normally internal to a MIDI synthesizer and hidden from outside view. One can, of |
| * course, learn from MIDI messages which notes the synthesizer is playing, and |
| * one might be able deduce something about the assignment of notes to voices. |
| * But MIDI itself does not provide a means to report which notes a |
| * synthesizer has assigned to which voice, nor even to report how many voices |
| * the synthesizer is capable of synthesizing. |
| * <p> |
| * In Java Sound, however, a |
| * <code>Synthesizer</code> class can expose the contents of its voices through its |
| * {@link Synthesizer#getVoiceStatus() getVoiceStatus()} method. |
| * This behavior is recommended but optional; |
| * synthesizers that don't expose their voice allocation simply return a |
| * zero-length array. A <code>Synthesizer</code> that does report its voice status |
| * should maintain this information at |
| * all times for all of its voices, whether they are currently sounding or |
| * not. In other words, a given type of <code>Synthesizer</code> always has a fixed |
| * number of voices, equal to the maximum number of simultaneous notes it is |
| * capable of sounding. |
| * <p> |
| * <A NAME="description_of_active"></A> |
| * If the voice is not currently processing a MIDI note, it |
| * is considered inactive. A voice is inactive when it has |
| * been given no note-on commands, or when every note-on command received has |
| * been terminated by a corresponding note-off (or by an "all notes off" |
| * message). For example, this happens when a synthesizer capable of playing 16 |
| * simultaneous notes is told to play a four-note chord; only |
| * four voices are active in this case (assuming no earlier notes are still playing). |
| * Usually, a voice whose status is reported as active is producing audible sound, but this |
| * is not always true; it depends on the details of the instrument (that |
| * is, the synthesis algorithm) and how long the note has been going on. |
| * For example, a voice may be synthesizing the sound of a single hand-clap. Because |
| * this sound dies away so quickly, it may become inaudible before a note-off |
| * message is received. In such a situation, the voice is still considered active |
| * even though no sound is currently being produced. |
| * <p> |
| * Besides its active or inactive status, the <code>VoiceStatus</code> class |
| * provides fields that reveal the voice's current MIDI channel, bank and |
| * program number, MIDI note number, and MIDI volume. All of these can |
| * change during the course of a voice. While the voice is inactive, each |
| * of these fields has an unspecified value, so you should check the active |
| * field first. |
| * |
| * @see Synthesizer#getMaxPolyphony |
| * @see Synthesizer#getVoiceStatus |
| * |
| * @author David Rivas |
| * @author Kara Kytle |
| */ |
| |
| public class VoiceStatus { |
| |
| |
| /** |
| * Indicates whether the voice is currently processing a MIDI note. |
| * See the explanation of |
| * <A HREF="#description_of_active">active and inactive voices</A>. |
| */ |
| public boolean active = false; |
| |
| |
| /** |
| * The MIDI channel on which this voice is playing. The value is a |
| * zero-based channel number if the voice is active, or |
| * unspecified if the voice is inactive. |
| * |
| * @see MidiChannel |
| * @see #active |
| */ |
| public int channel = 0; |
| |
| |
| /** |
| * The bank number of the instrument that this voice is currently using. |
| * This is a number dictated by the MIDI bank-select message; it does not |
| * refer to a <code>SoundBank</code> object. |
| * The value ranges from 0 to 16383 if the voice is active, and is |
| * unspecified if the voice is inactive. |
| * @see Patch |
| * @see Soundbank |
| * @see #active |
| * @see MidiChannel#programChange(int, int) |
| */ |
| public int bank = 0; |
| |
| |
| /** |
| * The program number of the instrument that this voice is currently using. |
| * The value ranges from 0 to 127 if the voice is active, and is |
| * unspecified if the voice is inactive. |
| * |
| * @see MidiChannel#getProgram |
| * @see Patch |
| * @see #active |
| */ |
| public int program = 0; |
| |
| |
| /** |
| * The MIDI note that this voice is playing. The range for an active voice |
| * is from 0 to 127 in semitones, with 60 referring to Middle C. |
| * The value is unspecified if the voice is inactive. |
| * |
| * @see MidiChannel#noteOn |
| * @see #active |
| */ |
| public int note = 0; |
| |
| |
| /** |
| * The current MIDI volume level for the voice. |
| * The value ranges from 0 to 127 if the voice is active, and is |
| * unspecified if the voice is inactive. |
| * <p> |
| * Note that this value does not necessarily reflect |
| * the instantaneous level of the sound produced by this |
| * voice; that level is the result of many contributing |
| * factors, including the current instrument and the |
| * shape of the amplitude envelope it produces. |
| * |
| * @see #active |
| */ |
| public int volume = 0; |
| } |