com.stainlesscode.mediapipeline.packetdecoder.MultispeedAudioPacketDecoder.java Source code

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Here is the source code for com.stainlesscode.mediapipeline.packetdecoder.MultispeedAudioPacketDecoder.java

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/*
 * Copyright 2010-2011 Stainless Code
 *
 *  This file is part of Daedalum.
 *
 *  Daedalum is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  Daedalum 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 for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with Daedalum.  If not, see <http://www.gnu.org/licenses/>.
 */

package com.stainlesscode.mediapipeline.packetdecoder;

import java.util.NoSuchElementException;

import org.apache.commons.collections.BufferOverflowException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.stainlesscode.mediapipeline.EngineRuntime;
import com.stainlesscode.mediapipeline.PacketDecoder;
import com.stainlesscode.mediapipeline.util.EngineThread;
import com.xuggle.xuggler.IAudioSamples;
import com.xuggle.xuggler.IPacket;

/**
 * Works like the MultispeedDemultiplexer by dropping every nth packet. This
 * also causes funky side-effects. A better approach is to interpolate the audio
 * so we have all audio data at hand.
 * 
 * @deprecated
 * @author Dan Stieglitz
 * 
 */
public class MultispeedAudioPacketDecoder extends EngineThread implements PacketDecoder {

    private static Logger LogUtil = LoggerFactory.getLogger(MultispeedAudioPacketDecoder.class);

    private EngineRuntime engineRuntime;
    private IAudioSamples samples = null;
    private boolean nextFrame = true;
    protected int multispeedPacketCounter = 0;
    protected int speed = 1;

    public MultispeedAudioPacketDecoder() {
    }

    public void init(EngineRuntime engineRuntime) {
        this.engineRuntime = engineRuntime;
    }

    @SuppressWarnings("unchecked")
    public void decodePacket(IPacket packet) {
        if (LogUtil.isDebugEnabled()) {
            LogUtil.debug("buffer size = " + engineRuntime.getAudioFrameBuffer().size());
            LogUtil.debug("decode audio packet " + packet.getTimeStamp());
        }

        try {
            if (nextFrame) {
                if (LogUtil.isDebugEnabled()) {
                    LogUtil.debug("starting a new frame");
                }
                samples = (IAudioSamples) engineRuntime.getAudioSamplePool().borrowObject();
                nextFrame = false;
            }

            int offset = 0;

            /*
             * Keep going until we've processed all data
             */
            while (offset < packet.getSize()) {
                int bytesDecoded = engineRuntime.getAudioCoder().decodeAudio(samples, packet, offset);
                if (bytesDecoded < 0)
                    throw new RuntimeException("got error decoding audio");
                offset += bytesDecoded;
                if (LogUtil.isDebugEnabled())
                    LogUtil.debug("decoded " + offset + " total bytes from packet");
            }

            /*
             * Some decoder will consume data in a packet, but will not be able
             * to construct a full set of samples yet. Therefore you should
             * always check if you got a complete set of samples from the
             * decoder
             */
            if (samples.isComplete()) {

                int modulo = 0;
                speed = new Double(engineRuntime.getPlaySpeed()).intValue();
                if (speed > 0) {
                    modulo = (multispeedPacketCounter++) % speed;
                    if (LogUtil.isDebugEnabled()) {
                        LogUtil.debug("speed factor is " + speed);
                        LogUtil.debug("modulo is " + modulo);
                    }
                }

                if (modulo == 0) {
                    try {
                        engineRuntime.getAudioFrameBuffer().add(samples);
                        if (LogUtil.isDebugEnabled())
                            LogUtil.debug("---> Decoded an audio frame");
                        nextFrame = true;
                    } catch (BufferOverflowException e) {
                        e.printStackTrace();
                    }
                }
            }

            if (packet != null)
                engineRuntime.getPacketPool().returnObject(packet);

        } catch (NoSuchElementException e) {
            e.printStackTrace();
        } catch (IllegalStateException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    @Override
    public void run() {
        while (!isMarkedForDeath()) {
            if (engineRuntime.getAudioPacketBuffer().isEmpty())
                continue;
            IPacket packet = (IPacket) engineRuntime.getAudioPacketBuffer().remove();
            if (packet != null) {
                decodePacket(packet);
            }
        }

        LogUtil.info("thread shutting down gracefully");
    }

}