1 /* 2 * Copyright 2008 CoreMedia AG, Hamburg 3 * 4 * Licensed under the Apache License, Version 2.0 (the License); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an AS IS BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.coremedia.iso.boxes; 18 19 20 import com.coremedia.iso.IsoTypeReader; 21 import com.coremedia.iso.IsoTypeWriter; 22 import com.googlecode.mp4parser.AbstractFullBox; 23 24 import java.io.IOException; 25 import java.nio.ByteBuffer; 26 import java.util.LinkedList; 27 import java.util.List; 28 29 import static com.googlecode.mp4parser.util.CastUtils.l2i; 30 31 /** 32 * <code> 33 * Box Type : 'elst'<br> 34 * Container: {@link EditBox}('edts')<br> 35 * Mandatory: No<br> 36 * Quantity : Zero or one</code><br><br> 37 * This box contains an explicit timeline map. Each entry defines part of the track time-line: by mapping part of 38 * the media time-line, or by indicating 'empty' time, or by defining a 'dwell', where a single time-point in the 39 * media is held for a period.<br> 40 * Note that edits are not restricted to fall on sample times. This means that when entering an edit, it can be 41 * necessary to (a) back up to a sync point, and pre-roll from there and then (b) be careful about the duration of 42 * the first sample - it might have been truncated if the edit enters it during its normal duration. If this is audio, 43 * that frame might need to be decoded, and then the final slicing done. Likewise, the duration of the last sample 44 * in an edit might need slicing. <br> 45 * Starting offsets for tracks (streams) are represented by an initial empty edit. For example, to play a track from 46 * its start for 30 seconds, but at 10 seconds into the presentation, we have the following edit list:<br> 47 * <p/> 48 * <li>Entry-count = 2</li> 49 * <li>Segment-duration = 10 seconds</li> 50 * <li>Media-Time = -1</li> 51 * <li>Media-Rate = 1</li> 52 * <li>Segment-duration = 30 seconds (could be the length of the whole track)</li> 53 * <li>Media-Time = 0 seconds</li> 54 * <li>Media-Rate = 1</li> 55 */ 56 public class EditListBox extends AbstractFullBox { 57 private List<Entry> entries = new LinkedList<Entry>(); 58 public static final String TYPE = "elst"; 59 EditListBox()60 public EditListBox() { 61 super(TYPE); 62 } 63 64 getEntries()65 public List<Entry> getEntries() { 66 return entries; 67 } 68 setEntries(List<Entry> entries)69 public void setEntries(List<Entry> entries) { 70 this.entries = entries; 71 } 72 getContentSize()73 protected long getContentSize() { 74 long contentSize = 8; 75 if (getVersion() == 1) { 76 contentSize += entries.size() * 20; 77 } else { 78 contentSize += entries.size() * 12; 79 } 80 81 return contentSize; 82 } 83 84 @Override _parseDetails(ByteBuffer content)85 public void _parseDetails(ByteBuffer content) { 86 parseVersionAndFlags(content); 87 int entryCount = l2i(IsoTypeReader.readUInt32(content)); 88 entries = new LinkedList<Entry>(); 89 for (int i = 0; i < entryCount; i++) { 90 entries.add(new Entry(this, content)); 91 92 } 93 } 94 95 @Override getContent(ByteBuffer byteBuffer)96 protected void getContent(ByteBuffer byteBuffer) { 97 writeVersionAndFlags(byteBuffer); 98 IsoTypeWriter.writeUInt32(byteBuffer, entries.size()); 99 for (Entry entry : entries) { 100 entry.getContent(byteBuffer); 101 } 102 } 103 104 @Override toString()105 public String toString() { 106 return "EditListBox{" + 107 "entries=" + entries + 108 '}'; 109 } 110 111 public static class Entry { 112 private long segmentDuration; 113 private long mediaTime; 114 private double mediaRate; 115 EditListBox editListBox; 116 117 /** 118 * Creates a new <code>Entry</code> with all values set. 119 * 120 * @param segmentDuration duration in movie timescale 121 * @param mediaTime starting time 122 * @param mediaRate relative play rate 123 */ Entry(EditListBox editListBox, long segmentDuration, long mediaTime, double mediaRate)124 public Entry(EditListBox editListBox, long segmentDuration, long mediaTime, double mediaRate) { 125 this.segmentDuration = segmentDuration; 126 this.mediaTime = mediaTime; 127 this.mediaRate = mediaRate; 128 this.editListBox = editListBox; 129 } 130 Entry(EditListBox editListBox, ByteBuffer bb)131 public Entry(EditListBox editListBox, ByteBuffer bb) { 132 if (editListBox.getVersion() == 1) { 133 segmentDuration = IsoTypeReader.readUInt64(bb); 134 mediaTime = IsoTypeReader.readUInt64(bb); 135 mediaRate = IsoTypeReader.readFixedPoint1616(bb); 136 } else { 137 segmentDuration = IsoTypeReader.readUInt32(bb); 138 mediaTime = IsoTypeReader.readUInt32(bb); 139 mediaRate = IsoTypeReader.readFixedPoint1616(bb); 140 } 141 this.editListBox = editListBox; 142 } 143 144 /** 145 * The segment duration is an integer that specifies the duration 146 * of this edit segment in units of the timescale in the Movie 147 * Header Box 148 * 149 * @return segment duration in movie timescale 150 */ getSegmentDuration()151 public long getSegmentDuration() { 152 return segmentDuration; 153 } 154 155 /** 156 * The segment duration is an integer that specifies the duration 157 * of this edit segment in units of the timescale in the Movie 158 * Header Box 159 * 160 * @param segmentDuration new segment duration in movie timescale 161 */ setSegmentDuration(long segmentDuration)162 public void setSegmentDuration(long segmentDuration) { 163 this.segmentDuration = segmentDuration; 164 } 165 166 /** 167 * The media time is an integer containing the starting time 168 * within the media of a specific edit segment(in media time 169 * scale units, in composition time) 170 * 171 * @return starting time 172 */ getMediaTime()173 public long getMediaTime() { 174 return mediaTime; 175 } 176 177 /** 178 * The media time is an integer containing the starting time 179 * within the media of a specific edit segment(in media time 180 * scale units, in composition time) 181 * 182 * @param mediaTime starting time 183 */ setMediaTime(long mediaTime)184 public void setMediaTime(long mediaTime) { 185 this.mediaTime = mediaTime; 186 } 187 188 /** 189 * The media rate specifies the relative rate at which to play the 190 * media corresponding to a specific edit segment. 191 * 192 * @return relative play rate 193 */ getMediaRate()194 public double getMediaRate() { 195 return mediaRate; 196 } 197 198 /** 199 * The media rate specifies the relative rate at which to play the 200 * media corresponding to a specific edit segment. 201 * 202 * @param mediaRate new relative play rate 203 */ setMediaRate(double mediaRate)204 public void setMediaRate(double mediaRate) { 205 this.mediaRate = mediaRate; 206 } 207 208 @Override equals(Object o)209 public boolean equals(Object o) { 210 if (this == o) return true; 211 if (o == null || getClass() != o.getClass()) return false; 212 213 Entry entry = (Entry) o; 214 215 if (mediaTime != entry.mediaTime) return false; 216 if (segmentDuration != entry.segmentDuration) return false; 217 218 return true; 219 } 220 221 @Override hashCode()222 public int hashCode() { 223 int result = (int) (segmentDuration ^ (segmentDuration >>> 32)); 224 result = 31 * result + (int) (mediaTime ^ (mediaTime >>> 32)); 225 return result; 226 } 227 getContent(ByteBuffer bb)228 public void getContent(ByteBuffer bb) { 229 if (editListBox.getVersion() == 1) { 230 IsoTypeWriter.writeUInt64(bb, segmentDuration); 231 IsoTypeWriter.writeUInt64(bb, mediaTime); 232 } else { 233 IsoTypeWriter.writeUInt32(bb, l2i(segmentDuration)); 234 bb.putInt(l2i(mediaTime)); 235 } 236 IsoTypeWriter.writeFixedPont1616(bb, mediaRate); 237 } 238 239 @Override toString()240 public String toString() { 241 return "Entry{" + 242 "segmentDuration=" + segmentDuration + 243 ", mediaTime=" + mediaTime + 244 ", mediaRate=" + mediaRate + 245 '}'; 246 } 247 } 248 } 249