rockbox/songdbj/org/tritonus/share/sampled/AudioFormats.java

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/*
* AudioFormats.java
*
* This file is part of Tritonus: http://www.tritonus.org/
*/
/*
* Copyright (c) 1999,2000 by Matthias Pfisterer
* Copyright (c) 1999 by Florian Bomers <http://www.bomers.de>
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Library General Public License as published
* by the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
/*
|<--- this code is formatted to fit into 80 columns --->|
*/
package org.tritonus.share.sampled;
import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioSystem;
public class AudioFormats
{
private static boolean doMatch(int i1, int i2)
{
return i1 == AudioSystem.NOT_SPECIFIED
|| i2 == AudioSystem.NOT_SPECIFIED
|| i1 == i2;
}
private static boolean doMatch(float f1, float f2)
{
return f1 == AudioSystem.NOT_SPECIFIED
|| f2 == AudioSystem.NOT_SPECIFIED
|| Math.abs(f1 - f2) < 1.0e-9;
}
/**
* Tests whether 2 AudioFormats have matching formats.
* A field matches when it is AudioSystem.NOT_SPECIFIED in
* at least one of the formats or the field is the same
* in both formats.<br>
* Exceptions:
* <ul>
* <li>Encoding must always be equal for a match.
* <li> For a match, endianness must be equal if SampleSizeInBits is not
* AudioSystem.NOT_SPECIFIED and greater than 8bit in both formats.<br>
* In other words: If SampleSizeInBits is AudioSystem.NOT_SPECIFIED
* in either format or both formats have a SampleSizeInBits<8,
* endianness does not matter.
* </ul>
* This is a proposition to be used as AudioFormat.matches.
* It can therefore be considered as a temporary workaround.
*/
// IDEA: create a special "NOT_SPECIFIED" encoding
// and a AudioFormat.Encoding.matches method.
public static boolean matches(AudioFormat format1,
AudioFormat format2)
{
//$$fb 19 Dec 99: endian must be checked, too.
//
// we do have a problem with redundant elements:
// e.g.
// encoding=ALAW || ULAW -> bigEndian and samplesizeinbits don't matter
// sample size in bits == 8 -> bigEndian doesn't matter
// sample size in bits > 8 -> PCM is always signed.
// This is an overall issue in JavaSound, I think.
// At present, it is not consistently implemented to support these
// redundancies and implicit definitions
//
// As a workaround of this issue I return in the converters
// all combinations, e.g. for ULAW I return bigEndian and !bigEndian formats.
/* old version
*/
// as proposed by florian
return format1.getEncoding().equals(format2.getEncoding())
&& (format2.getSampleSizeInBits()<=8
|| format1.getSampleSizeInBits()==AudioSystem.NOT_SPECIFIED
|| format2.getSampleSizeInBits()==AudioSystem.NOT_SPECIFIED
|| format1.isBigEndian()==format2.isBigEndian())
&& doMatch(format1.getChannels(),format2.getChannels())
&& doMatch(format1.getSampleSizeInBits(), format2.getSampleSizeInBits())
&& doMatch(format1.getFrameSize(), format2.getFrameSize())
&& doMatch(format1.getSampleRate(), format2.getSampleRate())
&& doMatch(format1.getFrameRate(),format2.getFrameRate());
}
/**
* Tests for exact equality of 2 AudioFormats.
* This is the behaviour of AudioFormat.matches in JavaSound 1.0.
* <p>
* This is a proposition to be used as AudioFormat.equals.
* It can therefore be considered as a temporary workaround.
*/
public static boolean equals(AudioFormat format1,
AudioFormat format2)
{
return format1.getEncoding().equals(format2.getEncoding())
&& format1.getChannels() == format2.getChannels()
&& format1.getSampleSizeInBits() == format2.getSampleSizeInBits()
&& format1.getFrameSize() == format2.getFrameSize()
&& (Math.abs(format1.getSampleRate() - format2.getSampleRate()) < 1.0e-9)
&& (Math.abs(format1.getFrameRate() - format2.getFrameRate()) < 1.0e-9);
}
}
/*** AudioFormats.java ***/