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	/*
	* Copyright (c) 2007, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* 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).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/
	package com.sun.media.sound;

	/**
	* A simple look-ahead volume limiter with very fast attack and fast release.
	* This filter is used for preventing clipping.
	*
	* @author Karl Helgason
	*/
	public final class SoftLimiter implements SoftAudioProcessor {

	float lastmax = 0;
	float gain = 1;
	float[] temp_bufferL;
	float[] temp_bufferR;
	boolean mix = false;
	SoftAudioBuffer bufferL;
	SoftAudioBuffer bufferR;
	SoftAudioBuffer bufferLout;
	SoftAudioBuffer bufferRout;
	float controlrate;

	public void init(float samplerate, float controlrate) {
	this.controlrate = controlrate;
	}

	public void setInput(int pin, SoftAudioBuffer input) {
	if (pin == 0)
	bufferL = input;
	if (pin == 1)
	bufferR = input;
	}

	public void setOutput(int pin, SoftAudioBuffer output) {
	if (pin == 0)
	bufferLout = output;
	if (pin == 1)
	bufferRout = output;
	}

	public void setMixMode(boolean mix) {
	this.mix = mix;
	}

	public void globalParameterControlChange(int[] slothpath, long param,
	long value) {
	}

	double silentcounter = 0;

	public void processAudio() {
	if (this.bufferL.isSilent()
	&& (this.bufferR == null \|\| this.bufferR.isSilent())) {
	silentcounter += 1 / controlrate;

	if (silentcounter > 60) {
	if (!mix) {
	bufferLout.clear();
	if (bufferRout != null) bufferRout.clear();
	}
	return;
	}
	} else
	silentcounter = 0;

	float[] bufferL = this.bufferL.array();
	float[] bufferR = this.bufferR == null ? null : this.bufferR.array();
	float[] bufferLout = this.bufferLout.array();
	float[] bufferRout = this.bufferRout == null
	? null : this.bufferRout.array();

	if (temp_bufferL == null \|\| temp_bufferL.length < bufferL.length)
	temp_bufferL = new float[bufferL.length];
	if (bufferR != null)
	if (temp_bufferR == null \|\| temp_bufferR.length < bufferR.length)
	temp_bufferR = new float[bufferR.length];

	float max = 0;
	int len = bufferL.length;

	if (bufferR == null) {
	for (int i = 0; i < len; i++) {
	if (bufferL[i] > max)
	max = bufferL[i];
	if (-bufferL[i] > max)
	max = -bufferL[i];
	}
	} else {
	for (int i = 0; i < len; i++) {
	if (bufferL[i] > max)
	max = bufferL[i];
	if (bufferR[i] > max)
	max = bufferR[i];
	if (-bufferL[i] > max)
	max = -bufferL[i];
	if (-bufferR[i] > max)
	max = -bufferR[i];
	}
	}

	float lmax = lastmax;
	lastmax = max;
	if (lmax > max)
	max = lmax;

	float newgain = 1;
	if (max > 0.99f)
	newgain = 0.99f / max;
	else
	newgain = 1;

	if (newgain > gain)
	newgain = (newgain + gain * 9) / 10f;

	float gaindelta = (newgain - gain) / len;
	if (mix) {
	if (bufferR == null) {
	for (int i = 0; i < len; i++) {
	gain += gaindelta;
	float bL = bufferL[i];
	float tL = temp_bufferL[i];
	temp_bufferL[i] = bL;
	bufferLout[i] += tL * gain;
	}
	} else {
	for (int i = 0; i < len; i++) {
	gain += gaindelta;
	float bL = bufferL[i];
	float bR = bufferR[i];
	float tL = temp_bufferL[i];
	float tR = temp_bufferR[i];
	temp_bufferL[i] = bL;
	temp_bufferR[i] = bR;
	bufferLout[i] += tL * gain;
	bufferRout[i] += tR * gain;
	}
	}

	} else {
	if (bufferR == null) {
	for (int i = 0; i < len; i++) {
	gain += gaindelta;
	float bL = bufferL[i];
	float tL = temp_bufferL[i];
	temp_bufferL[i] = bL;
	bufferLout[i] = tL * gain;
	}
	} else {
	for (int i = 0; i < len; i++) {
	gain += gaindelta;
	float bL = bufferL[i];
	float bR = bufferR[i];
	float tL = temp_bufferL[i];
	float tR = temp_bufferR[i];
	temp_bufferL[i] = bL;
	temp_bufferR[i] = bR;
	bufferLout[i] = tL * gain;
	bufferRout[i] = tR * gain;
	}
	}

	}
	gain = newgain;
	}

	public void processControlLogic() {
	}
	}

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