Java Examples in a Nutshell, 3rd Edition

Streaming Sounds with javax.sound

Sound files, especially sampled audio files in the uncompressed PCM format, are quite large, and, except for the shortest audio clips, it is not generally a good idea to read the entire file into memory. Instead, these files are typically played in streaming mode so that only the portion of the sound that is currently playing must reside in memory. In exchange for reduced memory consumption, we lose the ability to easily jump to any position within the sound, of course. Example 17-4 is a listing of PlaySoundStream, a program that plays streaming audio data read from the specified URL. It demonstrates streaming techniques for both sampled audio and MIDI data, and also demonstrates a transcoding technique for converting unsupported encodings (such as ALAW and ULAW) into PCM encoding so they can be played. PlaySoundStream is a console-based application with no GUI. Note the use of the wait( ) and notify( ) methods to make streamMidiSequence( ) into a modal method that does not return until the sound has finished playing. Note also that you must use a -m command-line argument in order to play MIDI data.

Example 17-4. PlaySoundStream.java

package je3.sound; import java.io.*; import java.net.*; import javax.sound.sampled.*; import javax.sound.midi.*; /** * This class plays sounds streaming from a URL: it does not have to preload * the entire sound into memory before playing it. It is a command-line * application with no gui. It includes code to convert ...