/*
* Copyright 2012 castLabs GmbH, Berlin
*
* Licensed under the Apache License, Version 2.0 (the License);
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an AS IS BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.googlecode.mp4parser.authoring.tracks;
import com.coremedia.iso.boxes.*;
import com.coremedia.iso.boxes.sampleentry.AudioSampleEntry;
import com.googlecode.mp4parser.authoring.AbstractTrack;
import com.googlecode.mp4parser.authoring.TrackMetaData;
import com.googlecode.mp4parser.boxes.AC3SpecificBox;
import com.googlecode.mp4parser.boxes.mp4.ESDescriptorBox;
import com.googlecode.mp4parser.boxes.mp4.objectdescriptors.*;
import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.ByteBuffer;
import java.util.*;
/**
*/
public class AACTrackImpl extends AbstractTrack {
public static Map<Integer, Integer> samplingFrequencyIndexMap = new HashMap<Integer, Integer>();
static {
samplingFrequencyIndexMap.put(96000, 0);
samplingFrequencyIndexMap.put(88200, 1);
samplingFrequencyIndexMap.put(64000, 2);
samplingFrequencyIndexMap.put(48000, 3);
samplingFrequencyIndexMap.put(44100, 4);
samplingFrequencyIndexMap.put(32000, 5);
samplingFrequencyIndexMap.put(24000, 6);
samplingFrequencyIndexMap.put(22050, 7);
samplingFrequencyIndexMap.put(16000, 8);
samplingFrequencyIndexMap.put(12000, 9);
samplingFrequencyIndexMap.put(11025, 10);
samplingFrequencyIndexMap.put(8000, 11);
samplingFrequencyIndexMap.put(0x0, 96000);
samplingFrequencyIndexMap.put(0x1, 88200);
samplingFrequencyIndexMap.put(0x2, 64000);
samplingFrequencyIndexMap.put(0x3, 48000);
samplingFrequencyIndexMap.put(0x4, 44100);
samplingFrequencyIndexMap.put(0x5, 32000);
samplingFrequencyIndexMap.put(0x6, 24000);
samplingFrequencyIndexMap.put(0x7, 22050);
samplingFrequencyIndexMap.put(0x8, 16000);
samplingFrequencyIndexMap.put(0x9, 12000);
samplingFrequencyIndexMap.put(0xa, 11025);
samplingFrequencyIndexMap.put(0xb, 8000);
}
TrackMetaData trackMetaData = new TrackMetaData();
SampleDescriptionBox sampleDescriptionBox;
int samplerate;
int bitrate;
int channelCount;
int channelconfig;
int bufferSizeDB;
long maxBitRate;
long avgBitRate;
private BufferedInputStream inputStream;
private List<ByteBuffer> samples;
boolean readSamples = false;
List<TimeToSampleBox.Entry> stts;
private String lang = "und";
public AACTrackImpl(InputStream inputStream, String lang) throws IOException {
this.lang = lang;
parse(inputStream);
}
public AACTrackImpl(InputStream inputStream) throws IOException {
parse(inputStream);
}
private void parse(InputStream inputStream) throws IOException {
this.inputStream = new BufferedInputStream(inputStream);
stts = new LinkedList<TimeToSampleBox.Entry>();
if (!readVariables()) {
throw new IOException();
}
samples = new LinkedList<ByteBuffer>();
if (!readSamples()) {
throw new IOException();
}
double packetsPerSecond = (double)samplerate / 1024.0;
double duration = samples.size() / packetsPerSecond;
long dataSize = 0;
LinkedList<Integer> queue = new LinkedList<Integer>();
for (int i = 0; i < samples.size(); i++) {
int size = samples.get(i).capacity();
dataSize += size;
queue.add(size);
while (queue.size() > packetsPerSecond) {
queue.pop();
}
if (queue.size() == (int) packetsPerSecond) {
int currSize = 0;
for (int j = 0 ; j < queue.size(); j++) {
currSize += queue.get(j);
}
double currBitrate = 8.0 * currSize / queue.size() * packetsPerSecond;
if (currBitrate > maxBitRate) {
maxBitRate = (int)currBitrate;
}
}
}
avgBitRate = (int) (8 * dataSize / duration);
bufferSizeDB = 1536; /* TODO: Calcultate this somehow! */
sampleDescriptionBox = new SampleDescriptionBox();
AudioSampleEntry audioSampleEntry = new AudioSampleEntry("mp4a");
audioSampleEntry.setChannelCount(2);
audioSampleEntry.setSampleRate(samplerate);
audioSampleEntry.setDataReferenceIndex(1);
audioSampleEntry.setSampleSize(16);
ESDescriptorBox esds = new ESDescriptorBox();
ESDescriptor descriptor = new ESDescriptor();
descriptor.setEsId(0);
SLConfigDescriptor slConfigDescriptor = new SLConfigDescriptor();
slConfigDescriptor.setPredefined(2);
descriptor.setSlConfigDescriptor(slConfigDescriptor);
DecoderConfigDescriptor decoderConfigDescriptor = new DecoderConfigDescriptor();
decoderConfigDescriptor.setObjectTypeIndication(0x40);
decoderConfigDescriptor.setStreamType(5);
decoderConfigDescriptor.setBufferSizeDB(bufferSizeDB);
decoderConfigDescriptor.setMaxBitRate(maxBitRate);
decoderConfigDescriptor.setAvgBitRate(avgBitRate);
AudioSpecificConfig audioSpecificConfig = new AudioSpecificConfig();
audioSpecificConfig.setAudioObjectType(2); // AAC LC
audioSpecificConfig.setSamplingFrequencyIndex(samplingFrequencyIndexMap.get(samplerate));
audioSpecificConfig.setChannelConfiguration(channelconfig);
decoderConfigDescriptor.setAudioSpecificInfo(audioSpecificConfig);
descriptor.setDecoderConfigDescriptor(decoderConfigDescriptor);
ByteBuffer data = descriptor.serialize();
esds.setData(data);
audioSampleEntry.addBox(esds);
sampleDescriptionBox.addBox(audioSampleEntry);
trackMetaData.setCreationTime(new Date());
trackMetaData.setModificationTime(new Date());
trackMetaData.setLanguage(lang);
trackMetaData.setTimescale(samplerate); // Audio tracks always use samplerate as timescale
}
public SampleDescriptionBox getSampleDescriptionBox() {
return sampleDescriptionBox;
}
public List<TimeToSampleBox.Entry> getDecodingTimeEntries() {
return stts;
}
public List<CompositionTimeToSample.Entry> getCompositionTimeEntries() {
return null;
}
public long[] getSyncSamples() {
return null;
}
public List<SampleDependencyTypeBox.Entry> getSampleDependencies() {
return null;
}
public TrackMetaData getTrackMetaData() {
return trackMetaData;
}
public String getHandler() {
return "soun";
}
public List<ByteBuffer> getSamples() {
return samples;
}
public Box getMediaHeaderBox() {
return new SoundMediaHeaderBox();
}
public SubSampleInformationBox getSubsampleInformationBox() {
return null;
}
private boolean readVariables() throws IOException {
byte[] data = new byte[100];
inputStream.mark(100);
if (100 != inputStream.read(data, 0, 100)) {
return false;
}
inputStream.reset(); // Rewind
ByteBuffer bb = ByteBuffer.wrap(data);
BitReaderBuffer brb = new BitReaderBuffer(bb);
int syncword = brb.readBits(12);
if (syncword != 0xfff) {
return false;
}
int id = brb.readBits(1);
int layer = brb.readBits(2);
int protectionAbsent = brb.readBits(1);
int profile = brb.readBits(2);
samplerate = samplingFrequencyIndexMap.get(brb.readBits(4));
brb.readBits(1);
channelconfig = brb.readBits(3);
int original = brb.readBits(1);
int home = brb.readBits(1);
int emphasis = brb.readBits(2);
return true;
}
private boolean readSamples() throws IOException {
if (readSamples) {
return true;
}
readSamples = true;
byte[] header = new byte[15];
boolean ret = false;
inputStream.mark(15);
while (-1 != inputStream.read(header)) {
ret = true;
ByteBuffer bb = ByteBuffer.wrap(header);
inputStream.reset();
BitReaderBuffer brb = new BitReaderBuffer(bb);
int syncword = brb.readBits(12);
if (syncword != 0xfff) {
return false;
}
brb.readBits(3);
int protectionAbsent = brb.readBits(1);
brb.readBits(14);
int frameSize = brb.readBits(13);
int bufferFullness = brb.readBits(11);
int noBlocks = brb.readBits(2);
int used = (int) Math.ceil(brb.getPosition() / 8.0);
if (protectionAbsent == 0) {
used += 2;
}
inputStream.skip(used);
frameSize -= used;
// System.out.println("Size: " + frameSize + " fullness: " + bufferFullness + " no blocks: " + noBlocks);
byte[] data = new byte[frameSize];
inputStream.read(data);
samples.add(ByteBuffer.wrap(data));
stts.add(new TimeToSampleBox.Entry(1, 1024));
inputStream.mark(15);
}
return ret;
}
@Override
public String toString() {
return "AACTrackImpl{" +
"samplerate=" + samplerate +
", bitrate=" + bitrate +
", channelCount=" + channelCount +
", channelconfig=" + channelconfig +
'}';
}
}
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