| /* |
| * 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.ArrayList; |
| import java.util.Collections; |
| import java.util.List; |
| |
| import static com.googlecode.mp4parser.util.CastUtils.l2i; |
| |
| /** |
| * This box contains a compact version of a table that allows indexing from decoding time to sample number. |
| * Other tables give sample sizes and pointers, from the sample number. Each entry in the table gives the |
| * number of consecutive samples with the same time delta, and the delta of those samples. By adding the |
| * deltas a complete time-to-sample map may be built.<br> |
| * The Decoding Time to Sample Box contains decode time delta's: <code>DT(n+1) = DT(n) + STTS(n)</code> where STTS(n) |
| * is the (uncompressed) table entry for sample n.<br> |
| * The sample entries are ordered by decoding time stamps; therefore the deltas are all non-negative. <br> |
| * The DT axis has a zero origin; <code>DT(i) = SUM(for j=0 to i-1 of delta(j))</code>, and the sum of all |
| * deltas gives the length of the media in the track (not mapped to the overall timescale, and not considering |
| * any edit list). <br> |
| * The Edit List Box provides the initial CT value if it is non-empty (non-zero). |
| */ |
| public class TimeToSampleBox extends AbstractFullBox { |
| public static final String TYPE = "stts"; |
| |
| List<Entry> entries = Collections.emptyList(); |
| |
| |
| public TimeToSampleBox() { |
| super(TYPE); |
| } |
| |
| protected long getContentSize() { |
| return 8 + entries.size() * 8; |
| } |
| |
| @Override |
| public void _parseDetails(ByteBuffer content) { |
| parseVersionAndFlags(content); |
| int entryCount = l2i(IsoTypeReader.readUInt32(content)); |
| entries = new ArrayList<Entry>(entryCount); |
| |
| for (int i = 0; i < entryCount; i++) { |
| entries.add(new Entry(IsoTypeReader.readUInt32(content), IsoTypeReader.readUInt32(content))); |
| } |
| |
| } |
| |
| @Override |
| protected void getContent(ByteBuffer byteBuffer) { |
| writeVersionAndFlags(byteBuffer); |
| IsoTypeWriter.writeUInt32(byteBuffer, entries.size()); |
| for (Entry entry : entries) { |
| IsoTypeWriter.writeUInt32(byteBuffer, entry.getCount()); |
| IsoTypeWriter.writeUInt32(byteBuffer, entry.getDelta()); |
| } |
| } |
| |
| public List<Entry> getEntries() { |
| return entries; |
| } |
| |
| public void setEntries(List<Entry> entries) { |
| this.entries = entries; |
| } |
| |
| public String toString() { |
| return "TimeToSampleBox[entryCount=" + entries.size() + "]"; |
| } |
| |
| public static class Entry { |
| long count; |
| long delta; |
| |
| public Entry(long count, long delta) { |
| this.count = count; |
| this.delta = delta; |
| } |
| |
| public long getCount() { |
| return count; |
| } |
| |
| public long getDelta() { |
| return delta; |
| } |
| |
| public void setCount(long count) { |
| this.count = count; |
| } |
| |
| public void setDelta(long delta) { |
| this.delta = delta; |
| } |
| |
| @Override |
| public String toString() { |
| return "Entry{" + |
| "count=" + count + |
| ", delta=" + delta + |
| '}'; |
| } |
| } |
| |
| /** |
| * Decompresses the list of entries and returns the list of decoding times. |
| * |
| * @return decoding time per sample |
| */ |
| public static long[] blowupTimeToSamples(List<TimeToSampleBox.Entry> entries) { |
| long numOfSamples = 0; |
| for (TimeToSampleBox.Entry entry : entries) { |
| numOfSamples += entry.getCount(); |
| } |
| assert numOfSamples <= Integer.MAX_VALUE; |
| long[] decodingTime = new long[(int) numOfSamples]; |
| |
| int current = 0; |
| |
| |
| for (TimeToSampleBox.Entry entry : entries) { |
| for (int i = 0; i < entry.getCount(); i++) { |
| decodingTime[current++] = entry.getDelta(); |
| } |
| } |
| |
| return decodingTime; |
| } |
| |
| |
| } |