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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
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* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package com.sun.media.sound;
import java.io.BufferedInputStream;
import java.io.DataInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import javax.sound.sampled.AudioFileFormat;
import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.UnsupportedAudioFileException;
/**
* AU file reader.
*
* @author Kara Kytle
* @author Jan Borgersen
* @author Florian Bomers
*/
public final class AuFileReader extends SunFileReader {
// METHODS TO IMPLEMENT AudioFileReader
/**
* Obtains the audio file format of the input stream provided. The stream must
* point to valid audio file data. In general, audio file providers may
* need to read some data from the stream before determining whether they
* support it. These parsers must
* be able to mark the stream, read enough data to determine whether they
* support the stream, and, if not, reset the stream's read pointer to its original
* position. If the input stream does not support this, this method may fail
* with an IOException.
* @param stream the input stream from which file format information should be
* extracted
* @return an <code>AudioFileFormat</code> object describing the audio file format
* @throws UnsupportedAudioFileException if the stream does not point to valid audio
* file data recognized by the system
* @throws IOException if an I/O exception occurs
* @see InputStream#markSupported
* @see InputStream#mark
*/
public AudioFileFormat getAudioFileFormat(InputStream stream) throws UnsupportedAudioFileException, IOException {
AudioFormat format = null;
AuFileFormat fileFormat = null;
int maxReadLength = 28;
boolean bigendian = false;
int magic = -1;
int headerSize = -1;
int dataSize = -1;
int encoding_local = -1;
int sampleRate = -1;
int frameRate = -1;
int frameSize = -1;
int channels = -1;
final int sampleSizeInBits;
int length = 0;
int nread = 0;
AudioFormat.Encoding encoding = null;
DataInputStream dis = new DataInputStream( stream );
dis.mark(maxReadLength);
magic = dis.readInt();
if (! (magic == AuFileFormat.AU_SUN_MAGIC) || (magic == AuFileFormat.AU_DEC_MAGIC) ||
(magic == AuFileFormat.AU_SUN_INV_MAGIC) || (magic == AuFileFormat.AU_DEC_INV_MAGIC) ) {
// not AU, reset the stream, place into exception, throw exception
dis.reset();
throw new UnsupportedAudioFileException("not an AU file");
}
if ((magic == AuFileFormat.AU_SUN_MAGIC) || (magic == AuFileFormat.AU_DEC_MAGIC)) {
bigendian = true; // otherwise little-endian
}
headerSize = (bigendian==true ? dis.readInt() : rllong(dis) ); nread += 4;
dataSize = (bigendian==true ? dis.readInt() : rllong(dis) ); nread += 4;
encoding_local = (bigendian==true ? dis.readInt() : rllong(dis) ); nread += 4;
sampleRate = (bigendian==true ? dis.readInt() : rllong(dis) ); nread += 4;
channels = (bigendian==true ? dis.readInt() : rllong(dis) ); nread += 4;
if (channels <= 0) {
dis.reset();
throw new UnsupportedAudioFileException("Invalid number of channels");
}
frameRate = sampleRate;
switch (encoding_local) {
case AuFileFormat.AU_ULAW_8:
encoding = AudioFormat.Encoding.ULAW;
sampleSizeInBits = 8;
break;
case AuFileFormat.AU_ALAW_8:
encoding = AudioFormat.Encoding.ALAW;
sampleSizeInBits = 8;
break;
case AuFileFormat.AU_LINEAR_8:
// $$jb: 04.29.99: 8bit linear is *signed*, not *unsigned*
encoding = AudioFormat.Encoding.PCM_SIGNED;
sampleSizeInBits = 8;
break;
case AuFileFormat.AU_LINEAR_16:
encoding = AudioFormat.Encoding.PCM_SIGNED;
sampleSizeInBits = 16;
break;
case AuFileFormat.AU_LINEAR_24:
encoding = AudioFormat.Encoding.PCM_SIGNED;
sampleSizeInBits = 24;
break;
case AuFileFormat.AU_LINEAR_32:
encoding = AudioFormat.Encoding.PCM_SIGNED;
sampleSizeInBits = 32;
break;
// $jb: 03.19.99: we don't support these ...
/* case AuFileFormat.AU_FLOAT:
encoding = new AudioFormat.FLOAT;
sampleSizeInBits = 32;
break;
case AuFileFormat.AU_DOUBLE:
encoding = new AudioFormat.DOUBLE;
sampleSizeInBits = 8;
break;
case AuFileFormat.AU_ADPCM_G721:
encoding = new AudioFormat.G721_ADPCM;
sampleSizeInBits = 16;
break;
case AuFileFormat.AU_ADPCM_G723_3:
encoding = new AudioFormat.G723_3;
sampleSize = 24;
SamplePerUnit = 8;
break;
case AuFileFormat.AU_ADPCM_G723_5:
encoding = new AudioFormat.G723_5;
sampleSize = 40;
SamplePerUnit = 8;
break;
*/
default:
// unsupported filetype, throw exception
dis.reset();
throw new UnsupportedAudioFileException("not a valid AU file");
}
frameSize = calculatePCMFrameSize(sampleSizeInBits, channels);
//$$fb 2002-11-02: fix for 4629669: AU file reader: problems with empty files
if( dataSize < 0 ) {
length = AudioSystem.NOT_SPECIFIED;
} else {
//$$fb 2003-10-20: fix for 4940459: AudioInputStream.getFrameLength() returns 0 instead of NOT_SPECIFIED
length = dataSize / frameSize;
}
format = new AudioFormat( encoding, (float)sampleRate, sampleSizeInBits,
channels, frameSize, (float)frameRate, bigendian);
fileFormat = new AuFileFormat( AudioFileFormat.Type.AU, dataSize+headerSize,
format, length);
dis.reset(); // Throws IOException
return fileFormat;
}
/**
* Obtains the audio file format of the URL provided. The URL must
* point to valid audio file data.
* @param url the URL from which file format information should be
* extracted
* @return an <code>AudioFileFormat</code> object describing the audio file format
* @throws UnsupportedAudioFileException if the URL does not point to valid audio
* file data recognized by the system
* @throws IOException if an I/O exception occurs
*/
public AudioFileFormat getAudioFileFormat(URL url) throws UnsupportedAudioFileException, IOException {
InputStream urlStream = null;
BufferedInputStream bis = null;
AudioFileFormat fileFormat = null;
AudioFormat format = null;
urlStream = url.openStream(); // throws IOException
try {
bis = new BufferedInputStream( urlStream, bisBufferSize );
fileFormat = getAudioFileFormat( bis ); // throws UnsupportedAudioFileException
} finally {
urlStream.close();
}
return fileFormat;
}
/**
* Obtains the audio file format of the File provided. The File must
* point to valid audio file data.
* @param file the File from which file format information should be
* extracted
* @return an <code>AudioFileFormat</code> object describing the audio file format
* @throws UnsupportedAudioFileException if the File does not point to valid audio
* file data recognized by the system
* @throws IOException if an I/O exception occurs
*/
public AudioFileFormat getAudioFileFormat(File file) throws UnsupportedAudioFileException, IOException {
FileInputStream fis = null;
BufferedInputStream bis = null;
AudioFileFormat fileFormat = null;
AudioFormat format = null;
fis = new FileInputStream( file ); // throws IOException
// part of fix for 4325421
try {
bis = new BufferedInputStream( fis, bisBufferSize );
fileFormat = getAudioFileFormat( bis ); // throws UnsupportedAudioFileException
} finally {
fis.close();
}
return fileFormat;
}
/**
* Obtains an audio stream from the input stream provided. The stream must
* point to valid audio file data. In general, audio file providers may
* need to read some data from the stream before determining whether they
* support it. These parsers must
* be able to mark the stream, read enough data to determine whether they
* support the stream, and, if not, reset the stream's read pointer to its original
* position. If the input stream does not support this, this method may fail
* with an IOException.
* @param stream the input stream from which the <code>AudioInputStream</code> should be
* constructed
* @return an <code>AudioInputStream</code> object based on the audio file data contained
* in the input stream.
* @throws UnsupportedAudioFileException if the stream does not point to valid audio
* file data recognized by the system
* @throws IOException if an I/O exception occurs
* @see InputStream#markSupported
* @see InputStream#mark
*/
public AudioInputStream getAudioInputStream(InputStream stream) throws UnsupportedAudioFileException, IOException {
DataInputStream dis = null;
int headerSize;
AudioFileFormat fileFormat = null;
AudioFormat format = null;
fileFormat = getAudioFileFormat( stream ); // throws UnsupportedAudioFileException, IOException
// if we passed this call, we have an AU file.
format = fileFormat.getFormat();
dis = new DataInputStream(stream);
// now seek past the header
dis.readInt(); // magic
headerSize = (format.isBigEndian()==true ? dis.readInt() : rllong(dis) );
dis.skipBytes( headerSize - 8 );
// we've got everything, and the stream should be at the
// beginning of the data chunk, so return an AudioInputStream.
return new AudioInputStream(dis, format, fileFormat.getFrameLength());
}
/**
* Obtains an audio stream from the URL provided. The URL must
* point to valid audio file data.
* @param url the URL for which the <code>AudioInputStream</code> should be
* constructed
* @return an <code>AudioInputStream</code> object based on the audio file data pointed
* to by the URL
* @throws UnsupportedAudioFileException if the URL does not point to valid audio
* file data recognized by the system
* @throws IOException if an I/O exception occurs
*/
public AudioInputStream getAudioInputStream(URL url) throws UnsupportedAudioFileException, IOException {
InputStream urlStream = null;
BufferedInputStream bis = null;
AudioFileFormat fileFormat = null;
urlStream = url.openStream(); // throws IOException
AudioInputStream result = null;
try {
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