1 /*
   2  * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package javax.sound.sampled.spi;
  27 
  28 import java.io.InputStream;
  29 
  30 import javax.sound.sampled.AudioFormat;
  31 import javax.sound.sampled.AudioInputStream;
  32 
  33 /**
  34  * A format conversion provider provides format conversion services
  35  * from one or more input formats to one or more output formats.
  36  * Converters include codecs, which encode and/or decode audio data,
  37  * as well as transcoders, etc.  Format converters provide methods for
  38  * determining what conversions are supported and for obtaining an audio
  39  * stream from which converted data can be read.
  40  * <p>
  41  * The source format represents the format of the incoming
  42  * audio data, which will be converted.
  43  * <p>
  44  * The target format represents the format of the processed, converted
  45  * audio data.  This is the format of the data that can be read from
  46  * the stream returned by one of the <code>getAudioInputStream</code> methods.
  47  *
  48  * @author Kara Kytle
  49  * @since 1.3
  50  */
  51 public abstract class FormatConversionProvider {
  52 
  53 
  54     // NEW METHODS
  55 
  56     /**
  57      * Obtains the set of source format encodings from which format
  58      * conversion services are provided by this provider.
  59      * @return array of source format encodings. If for some reason provider
  60      * does not provide any conversion services, an array of length 0 is
  61      * returned.
  62      */
  63     public abstract AudioFormat.Encoding[] getSourceEncodings();
  64 
  65 
  66     /**
  67      * Obtains the set of target format encodings to which format
  68      * conversion services are provided by this provider.
  69      * @return array of target format encodings. If for some reason provider
  70      * does not provide any conversion services, an array of length 0 is
  71      * returned.
  72      */
  73     public abstract AudioFormat.Encoding[] getTargetEncodings();
  74 
  75 
  76     /**
  77      * Indicates whether the format converter supports conversion from the
  78      * specified source format encoding.
  79      * @param sourceEncoding the source format encoding for which support is queried
  80      * @return <code>true</code> if the encoding is supported, otherwise <code>false</code>
  81      */
  82     public boolean isSourceEncodingSupported(AudioFormat.Encoding sourceEncoding){
  83 
  84         AudioFormat.Encoding sourceEncodings[] = getSourceEncodings();
  85 
  86         for(int i=0; i<sourceEncodings.length; i++) {
  87             if( sourceEncoding.equals( sourceEncodings[i]) ) {
  88                 return true;
  89             }
  90         }
  91         return false;
  92     }
  93 
  94 
  95     /**
  96      * Indicates whether the format converter supports conversion to the
  97      * specified target format encoding.
  98      * @param targetEncoding the target format encoding for which support is queried
  99      * @return <code>true</code> if the encoding is supported, otherwise <code>false</code>
 100      */
 101     public boolean isTargetEncodingSupported(AudioFormat.Encoding targetEncoding){
 102 
 103         AudioFormat.Encoding targetEncodings[] = getTargetEncodings();
 104 
 105         for(int i=0; i<targetEncodings.length; i++) {
 106             if( targetEncoding.equals( targetEncodings[i]) ) {
 107                 return true;
 108             }
 109         }
 110         return false;
 111     }
 112 
 113 
 114     /**
 115      * Obtains the set of target format encodings supported by the format converter
 116      * given a particular source format.
 117      * If no target format encodings are supported for this source format,
 118      * an array of length 0 is returned.
 119      * @param sourceFormat format of the incoming data
 120      * @return array of supported target format encodings.
 121      */
 122     public abstract AudioFormat.Encoding[] getTargetEncodings(AudioFormat sourceFormat);
 123 
 124 
 125     /**
 126      * Indicates whether the format converter supports conversion to a particular encoding
 127      * from a particular format.
 128      * @param targetEncoding desired encoding of the outgoing data
 129      * @param sourceFormat format of the incoming data
 130      * @return <code>true</code> if the conversion is supported, otherwise <code>false</code>
 131      */
 132     public boolean isConversionSupported(AudioFormat.Encoding targetEncoding, AudioFormat sourceFormat){
 133 
 134         AudioFormat.Encoding targetEncodings[] = getTargetEncodings(sourceFormat);
 135 
 136         for(int i=0; i<targetEncodings.length; i++) {
 137             if( targetEncoding.equals( targetEncodings[i]) ) {
 138                 return true;
 139             }
 140         }
 141         return false;
 142     }
 143 
 144 
 145     /**
 146      * Obtains the set of target formats with the encoding specified
 147      * supported by the format converter
 148      * If no target formats with the specified encoding are supported
 149      * for this source format, an array of length 0 is returned.
 150      * @param targetEncoding desired encoding of the stream after processing
 151      * @param sourceFormat format of the incoming data
 152      * @return array of supported target formats.
 153      */
 154     public abstract AudioFormat[] getTargetFormats(AudioFormat.Encoding targetEncoding, AudioFormat sourceFormat);
 155 
 156 
 157     /**
 158      * Indicates whether the format converter supports conversion to one
 159      * particular format from another.
 160      * @param targetFormat desired format of outgoing data
 161      * @param sourceFormat format of the incoming data
 162      * @return <code>true</code> if the conversion is supported, otherwise <code>false</code>
 163      */
 164     public boolean isConversionSupported(AudioFormat targetFormat, AudioFormat sourceFormat){
 165 
 166         AudioFormat targetFormats[] = getTargetFormats( targetFormat.getEncoding(), sourceFormat );
 167 
 168         for(int i=0; i<targetFormats.length; i++) {
 169             if( targetFormat.matches( targetFormats[i] ) ) {
 170                 return true;
 171             }
 172         }
 173         return false;
 174     }
 175 
 176 
 177     /**
 178      * Obtains an audio input stream with the specified encoding from the given audio
 179      * input stream.
 180      * @param targetEncoding desired encoding of the stream after processing
 181      * @param sourceStream stream from which data to be processed should be read
 182      * @return stream from which processed data with the specified target encoding may be read
 183      * @throws IllegalArgumentException if the format combination supplied is
 184      * not supported.
 185      */
 186     public abstract AudioInputStream getAudioInputStream(AudioFormat.Encoding targetEncoding, AudioInputStream sourceStream);
 187 
 188 
 189     /**
 190      * Obtains an audio input stream with the specified format from the given audio
 191      * input stream.
 192      * @param targetFormat desired data format of the stream after processing
 193      * @param sourceStream stream from which data to be processed should be read
 194      * @return stream from which processed data with the specified format may be read
 195      * @throws IllegalArgumentException if the format combination supplied is
 196      * not supported.
 197      */
 198     public abstract AudioInputStream getAudioInputStream(AudioFormat targetFormat, AudioInputStream sourceStream);
 199 
 200 }