/*
* Copyright 2008 CoreMedia AG, Hamburg
*
* 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.coremedia.iso.boxes;
import com.coremedia.iso.IsoTypeReader;
import com.coremedia.iso.IsoTypeWriter;
import com.googlecode.mp4parser.AbstractFullBox;
import java.nio.ByteBuffer;
import java.util.LinkedList;
import java.util.List;
import static com.googlecode.mp4parser.util.CastUtils.l2i;
/**
* <code>
* Box Type : 'elst'<br>
* Container: {@link EditBox}('edts')<br>
* Mandatory: No<br>
* Quantity : Zero or one</code><br><br>
* This box contains an explicit timeline map. Each entry defines part of the track time-line: by mapping part of
* the media time-line, or by indicating 'empty' time, or by defining a 'dwell', where a single time-point in the
* media is held for a period.<br>
* Note that edits are not restricted to fall on sample times. This means that when entering an edit, it can be
* necessary to (a) back up to a sync point, and pre-roll from there and then (b) be careful about the duration of
* the first sample - it might have been truncated if the edit enters it during its normal duration. If this is audio,
* that frame might need to be decoded, and then the final slicing done. Likewise, the duration of the last sample
* in an edit might need slicing. <br>
* Starting offsets for tracks (streams) are represented by an initial empty edit. For example, to play a track from
* its start for 30 seconds, but at 10 seconds into the presentation, we have the following edit list:<br>
* <p/>
* <li>Entry-count = 2</li>
* <li>Segment-duration = 10 seconds</li>
* <li>Media-Time = -1</li>
* <li>Media-Rate = 1</li>
* <li>Segment-duration = 30 seconds (could be the length of the whole track)</li>
* <li>Media-Time = 0 seconds</li>
* <li>Media-Rate = 1</li>
*/
public class EditListBox extends AbstractFullBox {
private List<Entry> entries = new LinkedList<Entry>();
public static final String TYPE = "elst";
public EditListBox() {
super(TYPE);
}
public List<Entry> getEntries() {
return entries;
}
public void setEntries(List<Entry> entries) {
this.entries = entries;
}
protected long getContentSize() {
long contentSize = 8;
if (getVersion() == 1) {
contentSize += entries.size() * 20;
} else {
contentSize += entries.size() * 12;
}
return contentSize;
}
@Override
public void _parseDetails(ByteBuffer content) {
parseVersionAndFlags(content);
int entryCount = l2i(IsoTypeReader.readUInt32(content));
entries = new LinkedList<Entry>();
for (int i = 0; i < entryCount; i++) {
entries.add(new Entry(this, content));
}
}
@Override
protected void getContent(ByteBuffer byteBuffer) {
writeVersionAndFlags(byteBuffer);
IsoTypeWriter.writeUInt32(byteBuffer, entries.size());
for (Entry entry : entries) {
entry.getContent(byteBuffer);
}
}
@Override
public String toString() {
return "EditListBox{" +
"entries=" + entries +
'}';
}
public static class Entry {
private long segmentDuration;
private long mediaTime;
private double mediaRate;
EditListBox editListBox;
/**
* Creates a new <code>Entry</code> with all values set.
*
* @param segmentDuration duration in movie timescale
* @param mediaTime starting time
* @param mediaRate relative play rate
*/
public Entry(EditListBox editListBox, long segmentDuration, long mediaTime, double mediaRate) {
this.segmentDuration = segmentDuration;
this.mediaTime = mediaTime;
this.mediaRate = mediaRate;
this.editListBox = editListBox;
}
public Entry(EditListBox editListBox, ByteBuffer bb) {
if (editListBox.getVersion() == 1) {
segmentDuration = IsoTypeReader.readUInt64(bb);
mediaTime = bb.getLong();
mediaRate = IsoTypeReader.readFixedPoint1616(bb);
} else {
segmentDuration = IsoTypeReader.readUInt32(bb);
mediaTime = bb.getInt();
mediaRate = IsoTypeReader.readFixedPoint1616(bb);
}
this.editListBox = editListBox;
}
/**
* The segment duration is an integer that specifies the duration
* of this edit segment in units of the timescale in the Movie
* Header Box
*
* @return segment duration in movie timescale
*/
public long getSegmentDuration() {
return segmentDuration;
}
/**
* The segment duration is an integer that specifies the duration
* of this edit segment in units of the timescale in the Movie
* Header Box
*
* @param segmentDuration new segment duration in movie timescale
*/
public void setSegmentDuration(long segmentDuration) {
this.segmentDuration = segmentDuration;
}
/**
* The media time is an integer containing the starting time
* within the media of a specific edit segment(in media time
* scale units, in composition time)
*
* @return starting time
*/
public long getMediaTime() {
return mediaTime;
}
/**
* The media time is an integer containing the starting time
* within the media of a specific edit segment(in media time
* scale units, in composition time)
*
* @param mediaTime starting time
*/
public void setMediaTime(long mediaTime) {
this.mediaTime = mediaTime;
}
/**
* The media rate specifies the relative rate at which to play the
* media corresponding to a specific edit segment.
*
* @return relative play rate
*/
public double getMediaRate() {
return mediaRate;
}
/**
* The media rate specifies the relative rate at which to play the
* media corresponding to a specific edit segment.
*
* @param mediaRate new relative play rate
*/
public void setMediaRate(double mediaRate) {
this.mediaRate = mediaRate;
}
@Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
if (o == null || getClass() != o.getClass()) {
return false;
}
Entry entry = (Entry) o;
if (mediaTime != entry.mediaTime) {
return false;
}
if (segmentDuration != entry.segmentDuration) {
return false;
}
return true;
}
@Override
public int hashCode() {
int result = (int) (segmentDuration ^ (segmentDuration >>> 32));
result = 31 * result + (int) (mediaTime ^ (mediaTime >>> 32));
return result;
}
public void getContent(ByteBuffer bb) {
if (editListBox.getVersion() == 1) {
IsoTypeWriter.writeUInt64(bb, segmentDuration);
IsoTypeWriter.writeUInt64(bb, mediaTime);
} else {
IsoTypeWriter.writeUInt32(bb, l2i(segmentDuration));
bb.putInt(l2i(mediaTime));
}
IsoTypeWriter.writeFixedPoint1616(bb, mediaRate);
}
@Override
public String toString() {
return "Entry{" +
"segmentDuration=" + segmentDuration +
", mediaTime=" + mediaTime +
", mediaRate=" + mediaRate +
'}';
}
}
}
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