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src/java.desktop/share/classes/javax/sound/sampled/AudioFormat.java

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  23  * questions.
  24  */
  25 
  26 package javax.sound.sampled;
  27 
  28 import java.util.Collections;
  29 import java.util.HashMap;
  30 import java.util.Map;
  31 import java.util.Objects;
  32 
  33 /**
  34  * {@code AudioFormat} is the class that specifies a particular arrangement of
  35  * data in a sound stream. By examining the information stored in the audio
  36  * format, you can discover how to interpret the bits in the binary sound data.
  37  * <p>
  38  * Every data line has an audio format associated with its data stream. The
  39  * audio format of a source (playback) data line indicates what kind of data the
  40  * data line expects to receive for output. For a target (capture) data line,
  41  * the audio format specifies the kind of the data that can be read from the
  42  * line.

  43  * Sound files also have audio formats, of course. The {@link AudioFileFormat}
  44  * class encapsulates an {@code AudioFormat} in addition to other, file-specific
  45  * information. Similarly, an {@link AudioInputStream} has an
  46  * {@code AudioFormat}.
  47  * <p>
  48  * The {@code AudioFormat} class accommodates a number of common sound-file
  49  * encoding techniques, including pulse-code modulation (PCM), mu-law encoding,
  50  * and a-law encoding. These encoding techniques are predefined, but service
  51  * providers can create new encoding types. The encoding that a specific format
  52  * uses is named by its {@code encoding} field.
  53  * <p>
  54  * In addition to the encoding, the audio format includes other properties that
  55  * further specify the exact arrangement of the data. These include the number
  56  * of channels, sample rate, sample size, byte order, frame rate, and frame
  57  * size. Sounds may have different numbers of audio channels: one for mono, two
  58  * for stereo. The sample rate measures how many "snapshots" (samples) of the
  59  * sound pressure are taken per second, per channel. (If the sound is stereo
  60  * rather than mono, two samples are actually measured at each instant of time:
  61  * one for the left channel, and another for the right channel; however, the
  62  * sample rate still measures the number per channel, so the rate is the same


  76  * <p>
  77  * An {@code AudioFormat} object can include a set of properties. A property is
  78  * a pair of key and value: the key is of type {@code String}, the associated
  79  * property value is an arbitrary object. Properties specify additional format
  80  * specifications, like the bit rate for compressed formats. Properties are
  81  * mainly used as a means to transport additional information of the audio
  82  * format to and from the service providers. Therefore, properties are ignored
  83  * in the {@link #matches(AudioFormat)} method. However, methods which rely on
  84  * the installed service providers, like
  85  * {@link AudioSystem#isConversionSupported (AudioFormat, AudioFormat)
  86  * isConversionSupported} may consider properties, depending on the respective
  87  * service provider implementation.
  88  * <p>
  89  * The following table lists some common properties which service providers
  90  * should use, if applicable:
  91  *
  92  * <table class="striped">
  93  * <caption>Audio Format Properties</caption>
  94  * <thead>
  95  *  <tr>
  96  *   <th>Property key</th>
  97  *   <th>Value type</th>
  98  *   <th>Description</th>
  99  *  </tr>
 100  * </thead>
 101  * <tbody>
 102  *  <tr>
 103  *   <td>&quot;bitrate&quot;</td>
 104  *   <td>{@link java.lang.Integer Integer}</td>
 105  *   <td>average bit rate in bits per second</td>
 106  *  </tr>
 107  *  <tr>
 108  *   <td>&quot;vbr&quot;</td>
 109  *   <td>{@link java.lang.Boolean Boolean}</td>
 110  *   <td>{@code true}, if the file is encoded in variable bit
 111  *       rate (VBR)</td>
 112  *  </tr>
 113  *  <tr>
 114  *   <td>&quot;quality&quot;</td>
 115  *   <td>{@link java.lang.Integer Integer}</td>
 116  *   <td>encoding/conversion quality, 1..100</td>
 117  *  </tr>
 118  * </tbody>
 119  * </table>
 120  * <p>
 121  * Vendors of service providers (plugins) are encouraged to seek information
 122  * about other already established properties in third party plugins, and follow
 123  * the same conventions.
 124  *
 125  * @author Kara Kytle
 126  * @author Florian Bomers
 127  * @see DataLine#getFormat
 128  * @see AudioInputStream#getFormat
 129  * @see AudioFileFormat
 130  * @see javax.sound.sampled.spi.FormatConversionProvider
 131  * @since 1.3
 132  */
 133 public class AudioFormat {
 134 
 135     /**
 136      * The audio encoding technique used by this format.
 137      */


 166 
 167     /**
 168      * Indicates whether the audio data is stored in big-endian or little-endian
 169      * order.
 170      */
 171     protected boolean bigEndian;
 172 
 173     /**
 174      * The set of properties.
 175      */
 176     private HashMap<String, Object> properties;
 177 
 178     /**
 179      * Constructs an {@code AudioFormat} with the given parameters. The encoding
 180      * specifies the convention used to represent the data. The other parameters
 181      * are further explained in the {@link AudioFormat class description}.
 182      *
 183      * @param  encoding the audio encoding technique
 184      * @param  sampleRate the number of samples per second
 185      * @param  sampleSizeInBits the number of bits in each sample
 186      * @param  channels the number of channels (1 for mono, 2 for stereo,
 187      *         and so on)
 188      * @param  frameSize the number of bytes in each frame
 189      * @param  frameRate the number of frames per second
 190      * @param  bigEndian indicates whether the data for a single sample is
 191      *         stored in big-endian byte order ({@code false} means
 192      *         little-endian)
 193      */
 194     public AudioFormat(Encoding encoding, float sampleRate, int sampleSizeInBits,
 195                        int channels, int frameSize, float frameRate, boolean bigEndian) {
 196 
 197         this.encoding = encoding;
 198         this.sampleRate = sampleRate;
 199         this.sampleSizeInBits = sampleSizeInBits;
 200         this.channels = channels;
 201         this.frameSize = frameSize;
 202         this.frameRate = frameRate;
 203         this.bigEndian = bigEndian;
 204         this.properties = null;
 205     }
 206 
 207     /**
 208      * Constructs an {@code AudioFormat} with the given parameters. The encoding
 209      * specifies the convention used to represent the data. The other parameters
 210      * are further explained in the {@link AudioFormat class description}.
 211      *
 212      * @param  encoding the audio encoding technique
 213      * @param  sampleRate the number of samples per second
 214      * @param  sampleSizeInBits the number of bits in each sample
 215      * @param  channels the number of channels (1 for mono, 2 for stereo, and so
 216      *         on)
 217      * @param  frameSize the number of bytes in each frame
 218      * @param  frameRate the number of frames per second
 219      * @param  bigEndian indicates whether the data for a single sample is
 220      *         stored in big-endian byte order ({@code false} means little-endian)

 221      * @param  properties a {@code Map<String, Object>} object containing format
 222      *         properties
 223      * @since 1.5
 224      */
 225     public AudioFormat(Encoding encoding, float sampleRate,
 226                        int sampleSizeInBits, int channels,
 227                        int frameSize, float frameRate,
 228                        boolean bigEndian, Map<String, Object> properties) {
 229         this(encoding, sampleRate, sampleSizeInBits, channels,
 230              frameSize, frameRate, bigEndian);
 231         this.properties = new HashMap<>(properties);
 232     }
 233 
 234     /**
 235      * Constructs an {@code AudioFormat} with a linear PCM encoding and the
 236      * given parameters. The frame size is set to the number of bytes required
 237      * to contain one sample from each channel, and the frame rate is set to the
 238      * sample rate.
 239      *
 240      * @param  sampleRate the number of samples per second


 259              sampleRate,
 260              bigEndian);
 261     }
 262 
 263     /**
 264      * Obtains the type of encoding for sounds in this format.
 265      *
 266      * @return the encoding type
 267      * @see Encoding#PCM_SIGNED
 268      * @see Encoding#PCM_UNSIGNED
 269      * @see Encoding#ULAW
 270      * @see Encoding#ALAW
 271      */
 272     public Encoding getEncoding() {
 273 
 274         return encoding;
 275     }
 276 
 277     /**
 278      * Obtains the sample rate. For compressed formats, the return value is the
 279      * sample rate of the uncompressed audio data. When this AudioFormat is used
 280      * for queries (e.g. {@link AudioSystem#isConversionSupported(AudioFormat,
 281      * AudioFormat) AudioSystem.isConversionSupported}) or capabilities (e.g.

 282      * {@link DataLine.Info#getFormats DataLine.Info.getFormats}), a sample rate
 283      * of {@code AudioSystem.NOT_SPECIFIED} means that any sample rate is
 284      * acceptable. {@code AudioSystem.NOT_SPECIFIED} is also returned when the
 285      * sample rate is not defined for this audio format.
 286      *
 287      * @return the number of samples per second, or
 288      *         {@code AudioSystem.NOT_SPECIFIED}
 289      * @see #getFrameRate()
 290      * @see AudioSystem#NOT_SPECIFIED
 291      */
 292     public float getSampleRate() {
 293 
 294         return sampleRate;
 295     }
 296 
 297     /**
 298      * Obtains the size of a sample. For compressed formats, the return value is
 299      * the sample size of the uncompressed audio data. When this AudioFormat is
 300      * used for queries (e.g. {@link AudioSystem#isConversionSupported(
 301      * AudioFormat,AudioFormat) AudioSystem.isConversionSupported}) or
 302      * capabilities (e.g.
 303      * {@link DataLine.Info#getFormats DataLine.Info.getFormats}), a sample size
 304      * of {@code AudioSystem.NOT_SPECIFIED} means that any sample size is
 305      * acceptable. {@code AudioSystem.NOT_SPECIFIED} is also returned when the
 306      * sample size is not defined for this audio format.
 307      *
 308      * @return the number of bits in each sample, or
 309      *         {@code AudioSystem.NOT_SPECIFIED}
 310      * @see #getFrameSize()
 311      * @see AudioSystem#NOT_SPECIFIED
 312      */
 313     public int getSampleSizeInBits() {
 314 
 315         return sampleSizeInBits;
 316     }
 317 
 318     /**
 319      * Obtains the number of channels. When this AudioFormat is used for queries
 320      * (e.g. {@link AudioSystem#isConversionSupported(AudioFormat, AudioFormat)
 321      * AudioSystem.isConversionSupported}) or capabilities (e.g.
 322      * {@link DataLine.Info#getFormats DataLine.Info.getFormats}), a return
 323      * value of {@code AudioSystem.NOT_SPECIFIED} means that any (positive)
 324      * number of channels is acceptable.
 325      *
 326      * @return The number of channels (1 for mono, 2 for stereo, etc.), or
 327      *         {@code AudioSystem.NOT_SPECIFIED}
 328      * @see AudioSystem#NOT_SPECIFIED
 329      */
 330     public int getChannels() {
 331 
 332         return channels;
 333     }
 334 
 335     /**
 336      * Obtains the frame size in bytes. When this AudioFormat is used for
 337      * queries (e.g. {@link AudioSystem#isConversionSupported(AudioFormat,
 338      * AudioFormat) AudioSystem.isConversionSupported}) or capabilities (e.g.
 339      * {@link DataLine.Info#getFormats DataLine.Info.getFormats}), a frame size
 340      * of {@code AudioSystem.NOT_SPECIFIED} means that any frame size is
 341      * acceptable. {@code AudioSystem.NOT_SPECIFIED} is also returned when the
 342      * frame size is not defined for this audio format.
 343      *
 344      * @return the number of bytes per frame, or
 345      *         {@code AudioSystem.NOT_SPECIFIED}
 346      * @see #getSampleSizeInBits()
 347      * @see AudioSystem#NOT_SPECIFIED
 348      */
 349     public int getFrameSize() {
 350 
 351         return frameSize;
 352     }
 353 
 354     /**
 355      * Obtains the frame rate in frames per second. When this AudioFormat is
 356      * used for queries (e.g. {@link AudioSystem#isConversionSupported(
 357      * AudioFormat,AudioFormat) AudioSystem.isConversionSupported}) or
 358      * capabilities (e.g.
 359      * {@link DataLine.Info#getFormats DataLine.Info.getFormats}), a frame rate
 360      * of {@code AudioSystem.NOT_SPECIFIED} means that any frame rate is
 361      * acceptable. {@code AudioSystem.NOT_SPECIFIED} is also returned when the
 362      * frame rate is not defined for this audio format.
 363      *
 364      * @return the number of frames per second, or
 365      *         {@code AudioSystem.NOT_SPECIFIED}
 366      * @see #getSampleRate()
 367      * @see AudioSystem#NOT_SPECIFIED
 368      */
 369     public float getFrameRate() {
 370 
 371         return frameRate;
 372     }
 373 
 374     /**
 375      * Indicates whether the audio data is stored in big-endian or little-endian
 376      * byte order. If the sample size is not more than one byte, the return
 377      * value is irrelevant.
 378      *


 534             + sFrameRate
 535             + sEndian;
 536 
 537     }
 538 
 539     /**
 540      * The {@code Encoding} class names the specific type of data representation
 541      * used for an audio stream. The encoding includes aspects of the sound
 542      * format other than the number of channels, sample rate, sample size, frame
 543      * rate, frame size, and byte order.
 544      * <p>
 545      * One ubiquitous type of audio encoding is pulse-code modulation (PCM),
 546      * which is simply a linear (proportional) representation of the sound
 547      * waveform. With PCM, the number stored in each sample is proportional to
 548      * the instantaneous amplitude of the sound pressure at that point in time.
 549      * The numbers may be signed or unsigned integers or floats. Besides PCM,
 550      * other encodings include mu-law and a-law, which are nonlinear mappings of
 551      * the sound amplitude that are often used for recording speech.
 552      * <p>
 553      * You can use a predefined encoding by referring to one of the static
 554      * objects created by this class, such as PCM_SIGNED or PCM_UNSIGNED.
 555      * Service providers can create new encodings, such as compressed audio
 556      * formats, and make these available through the {@link AudioSystem} class.

 557      * <p>
 558      * The {@code Encoding} class is static, so that all {@code AudioFormat}
 559      * objects that have the same encoding will refer to the same object (rather
 560      * than different instances of the same class). This allows matches to be
 561      * made by checking that two format's encodings are equal.
 562      *
 563      * @author Kara Kytle
 564      * @see AudioFormat
 565      * @see javax.sound.sampled.spi.FormatConversionProvider
 566      * @since 1.3
 567      */
 568     public static class Encoding {
 569 
 570         /**
 571          * Specifies signed, linear PCM data.
 572          */
 573         public static final Encoding PCM_SIGNED = new Encoding("PCM_SIGNED");
 574 
 575         /**
 576          * Specifies unsigned, linear PCM data.


 592         /**
 593          * Specifies a-law encoded data.
 594          */
 595         public static final Encoding ALAW = new Encoding("ALAW");
 596 
 597         /**
 598          * Encoding name.
 599          */
 600         private final String name;
 601 
 602         /**
 603          * Constructs a new encoding.
 604          *
 605          * @param  name the name of the new type of encoding
 606          */
 607         public Encoding(final String name) {
 608             this.name = name;
 609         }
 610 
 611         /**
 612          * Finalizes the equals method.





 613          */
 614         @Override
 615         public final boolean equals(final Object obj) {
 616             if (this == obj) {
 617                 return true;
 618             }
 619             if (!(obj instanceof Encoding)) {
 620                 return false;
 621             }
 622             return Objects.equals(name, ((Encoding) obj).name);
 623         }
 624 
 625         /**
 626          * Finalizes the hashCode method.


 627          */
 628         @Override
 629         public final int hashCode() {
 630             return name != null ? name.hashCode() : 0;
 631         }
 632 
 633         /**
 634          * Provides the {@code String} representation of the encoding. This
 635          * {@code String} is the same name that was passed to the constructor.
 636          * For the predefined encodings, the name is similar to the encoding's
 637          * variable (field) name. For example, {@code PCM_SIGNED.toString()}
 638          * returns the name "PCM_SIGNED".
 639          *
 640          * @return the encoding name
 641          */
 642         @Override
 643         public final String toString() {
 644             return name;
 645         }
 646     }


  23  * questions.
  24  */
  25 
  26 package javax.sound.sampled;
  27 
  28 import java.util.Collections;
  29 import java.util.HashMap;
  30 import java.util.Map;
  31 import java.util.Objects;
  32 
  33 /**
  34  * {@code AudioFormat} is the class that specifies a particular arrangement of
  35  * data in a sound stream. By examining the information stored in the audio
  36  * format, you can discover how to interpret the bits in the binary sound data.
  37  * <p>
  38  * Every data line has an audio format associated with its data stream. The
  39  * audio format of a source (playback) data line indicates what kind of data the
  40  * data line expects to receive for output. For a target (capture) data line,
  41  * the audio format specifies the kind of the data that can be read from the
  42  * line.
  43  * <p>
  44  * Sound files also have audio formats, of course. The {@link AudioFileFormat}
  45  * class encapsulates an {@code AudioFormat} in addition to other, file-specific
  46  * information. Similarly, an {@link AudioInputStream} has an
  47  * {@code AudioFormat}.
  48  * <p>
  49  * The {@code AudioFormat} class accommodates a number of common sound-file
  50  * encoding techniques, including pulse-code modulation (PCM), mu-law encoding,
  51  * and a-law encoding. These encoding techniques are predefined, but service
  52  * providers can create new encoding types. The encoding that a specific format
  53  * uses is named by its {@code encoding} field.
  54  * <p>
  55  * In addition to the encoding, the audio format includes other properties that
  56  * further specify the exact arrangement of the data. These include the number
  57  * of channels, sample rate, sample size, byte order, frame rate, and frame
  58  * size. Sounds may have different numbers of audio channels: one for mono, two
  59  * for stereo. The sample rate measures how many "snapshots" (samples) of the
  60  * sound pressure are taken per second, per channel. (If the sound is stereo
  61  * rather than mono, two samples are actually measured at each instant of time:
  62  * one for the left channel, and another for the right channel; however, the
  63  * sample rate still measures the number per channel, so the rate is the same


  77  * <p>
  78  * An {@code AudioFormat} object can include a set of properties. A property is
  79  * a pair of key and value: the key is of type {@code String}, the associated
  80  * property value is an arbitrary object. Properties specify additional format
  81  * specifications, like the bit rate for compressed formats. Properties are
  82  * mainly used as a means to transport additional information of the audio
  83  * format to and from the service providers. Therefore, properties are ignored
  84  * in the {@link #matches(AudioFormat)} method. However, methods which rely on
  85  * the installed service providers, like
  86  * {@link AudioSystem#isConversionSupported (AudioFormat, AudioFormat)
  87  * isConversionSupported} may consider properties, depending on the respective
  88  * service provider implementation.
  89  * <p>
  90  * The following table lists some common properties which service providers
  91  * should use, if applicable:
  92  *
  93  * <table class="striped">
  94  * <caption>Audio Format Properties</caption>
  95  * <thead>
  96  *   <tr>
  97  *     <th>Property key
  98  *     <th>Value type
  99  *     <th>Description

 100  * </thead>
 101  * <tbody>
 102  *   <tr>
 103  *     <td>&quot;bitrate&quot;
 104  *     <td>{@link java.lang.Integer Integer}
 105  *     <td>average bit rate in bits per second

 106  *   <tr>
 107  *     <td>&quot;vbr&quot;
 108  *     <td>{@link java.lang.Boolean Boolean}
 109  *     <td>{@code true}, if the file is encoded in variable bit rate (VBR)


 110  *   <tr>
 111  *     <td>&quot;quality&quot;
 112  *     <td>{@link java.lang.Integer Integer}
 113  *     <td>encoding/conversion quality, 1..100

 114  * </tbody>
 115  * </table>
 116  * <p>
 117  * Vendors of service providers (plugins) are encouraged to seek information
 118  * about other already established properties in third party plugins, and follow
 119  * the same conventions.
 120  *
 121  * @author Kara Kytle
 122  * @author Florian Bomers
 123  * @see DataLine#getFormat
 124  * @see AudioInputStream#getFormat
 125  * @see AudioFileFormat
 126  * @see javax.sound.sampled.spi.FormatConversionProvider
 127  * @since 1.3
 128  */
 129 public class AudioFormat {
 130 
 131     /**
 132      * The audio encoding technique used by this format.
 133      */


 162 
 163     /**
 164      * Indicates whether the audio data is stored in big-endian or little-endian
 165      * order.
 166      */
 167     protected boolean bigEndian;
 168 
 169     /**
 170      * The set of properties.
 171      */
 172     private HashMap<String, Object> properties;
 173 
 174     /**
 175      * Constructs an {@code AudioFormat} with the given parameters. The encoding
 176      * specifies the convention used to represent the data. The other parameters
 177      * are further explained in the {@link AudioFormat class description}.
 178      *
 179      * @param  encoding the audio encoding technique
 180      * @param  sampleRate the number of samples per second
 181      * @param  sampleSizeInBits the number of bits in each sample
 182      * @param  channels the number of channels (1 for mono, 2 for stereo, and so
 183      *         on)
 184      * @param  frameSize the number of bytes in each frame
 185      * @param  frameRate the number of frames per second
 186      * @param  bigEndian indicates whether the data for a single sample is
 187      *         stored in big-endian byte order ({@code false} means
 188      *         little-endian)
 189      */
 190     public AudioFormat(Encoding encoding, float sampleRate, int sampleSizeInBits,
 191                        int channels, int frameSize, float frameRate, boolean bigEndian) {
 192 
 193         this.encoding = encoding;
 194         this.sampleRate = sampleRate;
 195         this.sampleSizeInBits = sampleSizeInBits;
 196         this.channels = channels;
 197         this.frameSize = frameSize;
 198         this.frameRate = frameRate;
 199         this.bigEndian = bigEndian;
 200         this.properties = null;
 201     }
 202 
 203     /**
 204      * Constructs an {@code AudioFormat} with the given parameters. The encoding
 205      * specifies the convention used to represent the data. The other parameters
 206      * are further explained in the {@link AudioFormat class description}.
 207      *
 208      * @param  encoding the audio encoding technique
 209      * @param  sampleRate the number of samples per second
 210      * @param  sampleSizeInBits the number of bits in each sample
 211      * @param  channels the number of channels (1 for mono, 2 for stereo, and so
 212      *         on)
 213      * @param  frameSize the number of bytes in each frame
 214      * @param  frameRate the number of frames per second
 215      * @param  bigEndian indicates whether the data for a single sample is
 216      *         stored in big-endian byte order ({@code false} means
 217      *         little-endian)
 218      * @param  properties a {@code Map<String, Object>} object containing format
 219      *         properties
 220      * @since 1.5
 221      */
 222     public AudioFormat(Encoding encoding, float sampleRate,
 223                        int sampleSizeInBits, int channels,
 224                        int frameSize, float frameRate,
 225                        boolean bigEndian, Map<String, Object> properties) {
 226         this(encoding, sampleRate, sampleSizeInBits, channels,
 227              frameSize, frameRate, bigEndian);
 228         this.properties = new HashMap<>(properties);
 229     }
 230 
 231     /**
 232      * Constructs an {@code AudioFormat} with a linear PCM encoding and the
 233      * given parameters. The frame size is set to the number of bytes required
 234      * to contain one sample from each channel, and the frame rate is set to the
 235      * sample rate.
 236      *
 237      * @param  sampleRate the number of samples per second


 256              sampleRate,
 257              bigEndian);
 258     }
 259 
 260     /**
 261      * Obtains the type of encoding for sounds in this format.
 262      *
 263      * @return the encoding type
 264      * @see Encoding#PCM_SIGNED
 265      * @see Encoding#PCM_UNSIGNED
 266      * @see Encoding#ULAW
 267      * @see Encoding#ALAW
 268      */
 269     public Encoding getEncoding() {
 270 
 271         return encoding;
 272     }
 273 
 274     /**
 275      * Obtains the sample rate. For compressed formats, the return value is the
 276      * sample rate of the uncompressed audio data. When this {@code AudioFormat}
 277      * is used for queries (e.g.
 278      * {@link AudioSystem#isConversionSupported(AudioFormat, AudioFormat)
 279      * AudioSystem.isConversionSupported}) or capabilities (e.g.
 280      * {@link DataLine.Info#getFormats DataLine.Info.getFormats}), a sample rate
 281      * of {@code AudioSystem.NOT_SPECIFIED} means that any sample rate is
 282      * acceptable. {@code AudioSystem.NOT_SPECIFIED} is also returned when the
 283      * sample rate is not defined for this audio format.
 284      *
 285      * @return the number of samples per second, or
 286      *         {@code AudioSystem.NOT_SPECIFIED}
 287      * @see #getFrameRate()
 288      * @see AudioSystem#NOT_SPECIFIED
 289      */
 290     public float getSampleRate() {
 291 
 292         return sampleRate;
 293     }
 294 
 295     /**
 296      * Obtains the size of a sample. For compressed formats, the return value is
 297      * the sample size of the uncompressed audio data. When this
 298      * {@code AudioFormat} is used for queries (e.g.
 299      * {@link AudioSystem#isConversionSupported(AudioFormat,AudioFormat)
 300      * AudioSystem.isConversionSupported}) or capabilities (e.g.
 301      * {@link DataLine.Info#getFormats DataLine.Info.getFormats}), a sample size
 302      * of {@code AudioSystem.NOT_SPECIFIED} means that any sample size is
 303      * acceptable. {@code AudioSystem.NOT_SPECIFIED} is also returned when the
 304      * sample size is not defined for this audio format.
 305      *
 306      * @return the number of bits in each sample, or
 307      *         {@code AudioSystem.NOT_SPECIFIED}
 308      * @see #getFrameSize()
 309      * @see AudioSystem#NOT_SPECIFIED
 310      */
 311     public int getSampleSizeInBits() {
 312 
 313         return sampleSizeInBits;
 314     }
 315 
 316     /**
 317      * Obtains the number of channels. When this {@code AudioFormat} is used for
 318      * queries (e.g. {@link AudioSystem#isConversionSupported(AudioFormat,
 319      * AudioFormat) AudioSystem.isConversionSupported}) or capabilities (e.g.
 320      * {@link DataLine.Info#getFormats DataLine.Info.getFormats}), a return
 321      * value of {@code AudioSystem.NOT_SPECIFIED} means that any (positive)
 322      * number of channels is acceptable.
 323      *
 324      * @return The number of channels (1 for mono, 2 for stereo, etc.), or
 325      *         {@code AudioSystem.NOT_SPECIFIED}
 326      * @see AudioSystem#NOT_SPECIFIED
 327      */
 328     public int getChannels() {
 329 
 330         return channels;
 331     }
 332 
 333     /**
 334      * Obtains the frame size in bytes. When this {@code AudioFormat} is used
 335      * for queries (e.g. {@link AudioSystem#isConversionSupported(AudioFormat,
 336      * AudioFormat) AudioSystem.isConversionSupported}) or capabilities (e.g.
 337      * {@link DataLine.Info#getFormats DataLine.Info.getFormats}), a frame size
 338      * of {@code AudioSystem.NOT_SPECIFIED} means that any frame size is
 339      * acceptable. {@code AudioSystem.NOT_SPECIFIED} is also returned when the
 340      * frame size is not defined for this audio format.
 341      *
 342      * @return the number of bytes per frame, or
 343      *         {@code AudioSystem.NOT_SPECIFIED}
 344      * @see #getSampleSizeInBits()
 345      * @see AudioSystem#NOT_SPECIFIED
 346      */
 347     public int getFrameSize() {
 348 
 349         return frameSize;
 350     }
 351 
 352     /**
 353      * Obtains the frame rate in frames per second. When this
 354      * {@code AudioFormat} is used for queries (e.g.
 355      * {@link AudioSystem#isConversionSupported(AudioFormat,AudioFormat)
 356      * AudioSystem.isConversionSupported}) or capabilities (e.g.
 357      * {@link DataLine.Info#getFormats DataLine.Info.getFormats}), a frame rate
 358      * of {@code AudioSystem.NOT_SPECIFIED} means that any frame rate is
 359      * acceptable. {@code AudioSystem.NOT_SPECIFIED} is also returned when the
 360      * frame rate is not defined for this audio format.
 361      *
 362      * @return the number of frames per second, or
 363      *         {@code AudioSystem.NOT_SPECIFIED}
 364      * @see #getSampleRate()
 365      * @see AudioSystem#NOT_SPECIFIED
 366      */
 367     public float getFrameRate() {
 368 
 369         return frameRate;
 370     }
 371 
 372     /**
 373      * Indicates whether the audio data is stored in big-endian or little-endian
 374      * byte order. If the sample size is not more than one byte, the return
 375      * value is irrelevant.
 376      *


 532             + sFrameRate
 533             + sEndian;
 534 
 535     }
 536 
 537     /**
 538      * The {@code Encoding} class names the specific type of data representation
 539      * used for an audio stream. The encoding includes aspects of the sound
 540      * format other than the number of channels, sample rate, sample size, frame
 541      * rate, frame size, and byte order.
 542      * <p>
 543      * One ubiquitous type of audio encoding is pulse-code modulation (PCM),
 544      * which is simply a linear (proportional) representation of the sound
 545      * waveform. With PCM, the number stored in each sample is proportional to
 546      * the instantaneous amplitude of the sound pressure at that point in time.
 547      * The numbers may be signed or unsigned integers or floats. Besides PCM,
 548      * other encodings include mu-law and a-law, which are nonlinear mappings of
 549      * the sound amplitude that are often used for recording speech.
 550      * <p>
 551      * You can use a predefined encoding by referring to one of the static
 552      * objects created by this class, such as {@code PCM_SIGNED} or
 553      * {@code PCM_UNSIGNED}. Service providers can create new encodings, such as
 554      * compressed audio formats, and make these available through the
 555      * {@link AudioSystem} class.
 556      * <p>
 557      * The {@code Encoding} class is static, so that all {@code AudioFormat}
 558      * objects that have the same encoding will refer to the same object (rather
 559      * than different instances of the same class). This allows matches to be
 560      * made by checking that two format's encodings are equal.
 561      *
 562      * @author Kara Kytle
 563      * @see AudioFormat
 564      * @see javax.sound.sampled.spi.FormatConversionProvider
 565      * @since 1.3
 566      */
 567     public static class Encoding {
 568 
 569         /**
 570          * Specifies signed, linear PCM data.
 571          */
 572         public static final Encoding PCM_SIGNED = new Encoding("PCM_SIGNED");
 573 
 574         /**
 575          * Specifies unsigned, linear PCM data.


 591         /**
 592          * Specifies a-law encoded data.
 593          */
 594         public static final Encoding ALAW = new Encoding("ALAW");
 595 
 596         /**
 597          * Encoding name.
 598          */
 599         private final String name;
 600 
 601         /**
 602          * Constructs a new encoding.
 603          *
 604          * @param  name the name of the new type of encoding
 605          */
 606         public Encoding(final String name) {
 607             this.name = name;
 608         }
 609 
 610         /**
 611          * Indicates whether the specified object is equal to this encoding,
 612          * returning {@code true} if the objects are the same.
 613          *
 614          * @param  obj the reference object with which to compare
 615          * @return {@code true} if this encoding is the same as the {@code obj}
 616          *         argument; {@code false} otherwise
 617          */
 618         @Override
 619         public final boolean equals(final Object obj) {
 620             if (this == obj) {
 621                 return true;
 622             }
 623             if (!(obj instanceof Encoding)) {
 624                 return false;
 625             }
 626             return Objects.equals(name, ((Encoding) obj).name);
 627         }
 628 
 629         /**
 630          * Returns a hash code value for this encoding.
 631          *
 632          * @return a hash code value for this encoding
 633          */
 634         @Override
 635         public final int hashCode() {
 636             return name != null ? name.hashCode() : 0;
 637         }
 638 
 639         /**
 640          * Provides the {@code String} representation of the encoding. This
 641          * {@code String} is the same name that was passed to the constructor.
 642          * For the predefined encodings, the name is similar to the encoding's
 643          * variable (field) name. For example, {@code PCM_SIGNED.toString()}
 644          * returns the name "PCM_SIGNED".
 645          *
 646          * @return the encoding name
 647          */
 648         @Override
 649         public final String toString() {
 650             return name;
 651         }
 652     }
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