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Class AudioFormat.Encoding

  extended by javax.sound.sampled.AudioFormat.Encoding
Enclosing class:

public static class AudioFormat.Encoding
extends Object

The Encoding class names the specific type of data representation used for an audio stream. The encoding includes aspects of the sound format other than the number of channels, sample rate, sample size, frame rate, frame size, and byte order.

One ubiquitous type of audio encoding is pulse-code modulation (PCM), which is simply a linear (proportional) representation of the sound waveform. With PCM, the number stored in each sample is proportional to the instantaneous amplitude of the sound pressure at that point in time. The numbers are frequently signed or unsigned integers. Besides PCM, other encodings include mu-law and a-law, which are nonlinear mappings of the sound amplitude that are often used for recording speech.

You can use a predefined encoding by referring to one of the static objects created by this class, such as PCM_SIGNED or PCM_UNSIGNED. Service providers can create new encodings, such as compressed audio formats or floating-point PCM samples, and make these available through the AudioSystem class.

The Encoding class is static, so that all AudioFormat objects that have the same encoding will refer to the same object (rather than different instances of the same class). This allows matches to be made by checking that two format's encodings are equal.

See Also:
AudioFormat, FormatConversionProvider

Field Summary
static AudioFormat.Encoding ALAW
          Specifies a-law encoded data.
static AudioFormat.Encoding PCM_SIGNED
          Specifies signed, linear PCM data.
static AudioFormat.Encoding PCM_UNSIGNED
          Specifies unsigned, linear PCM data.
static AudioFormat.Encoding ULAW
          Specifies u-law encoded data.
Constructor Summary
AudioFormat.Encoding(String name)
          Constructs a new encoding.
Method Summary
 boolean equals(Object obj)
          Finalizes the equals method
 int hashCode()
          Finalizes the hashCode method
 String toString()
          Provides the String representation of the encoding.
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail


public static final AudioFormat.Encoding PCM_SIGNED
Specifies signed, linear PCM data.


public static final AudioFormat.Encoding PCM_UNSIGNED
Specifies unsigned, linear PCM data.


public static final AudioFormat.Encoding ULAW
Specifies u-law encoded data.


public static final AudioFormat.Encoding ALAW
Specifies a-law encoded data.

Constructor Detail


public AudioFormat.Encoding(String name)
Constructs a new encoding.

name - the name of the new type of encoding
Method Detail


public final boolean equals(Object obj)
Finalizes the equals method

equals in class Object
obj - the other object.
if this and other are considered equal.


public final int hashCode()
Finalizes the hashCode method

hashCode in class Object
a hash code value.


public final String toString()
Provides the String representation of the encoding. This String is the same name that was passed to the constructor. For the predefined encodings, the name is similar to the encoding's variable (field) name. For example, PCM_SIGNED.toString() returns the name "pcm_signed".

toString in class Object
the encoding name

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