/*
* Copyright (C) 2011 in-somnia
*
* This file is part of JAAD.
*
* JAAD is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 3 of the
* License, or (at your option) any later version.
*
* JAAD 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 Lesser General
* Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library.
* If not, see <http://www.gnu.org/licenses/>.
*/
package net.sourceforge.jaad.mp4.boxes.impl;
import net.sourceforge.jaad.mp4.boxes.FullBox;
import net.sourceforge.jaad.mp4.MP4InputStream;
import java.io.IOException;
/**
* 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.
* The Decoding Time to Sample Box contains decode time delta's:
* DT(n+1) = DT(n) + STTS(n)
* where STTS(n) is the (uncompressed) table entry for sample n.
* The sample entries are ordered by decoding time stamps; therefore the deltas
* are all non-negative.
* The DT axis has a zero origin; DT(i) = SUM(for j=0 to i-1 of delta(j)), 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).
* The Edit List Box provides the initial CT value if it is non-empty
* (non-zero).
*
* @author in-somnia
*/
public class DecodingTimeToSampleBox extends FullBox {
private long[] sampleCounts, sampleDeltas;
public DecodingTimeToSampleBox() {
super("Time To Sample Box");
}
@Override
public void decode(MP4InputStream in) throws IOException {
super.decode(in);
final int entryCount = (int) in.readBytes(4);
sampleCounts = new long[entryCount];
sampleDeltas = new long[entryCount];
for(int i = 0; i<entryCount; i++) {
sampleCounts[i] = in.readBytes(4);
sampleDeltas[i] = in.readBytes(4);
}
}
public long[] getSampleCounts() {
return sampleCounts;
}
public long[] getSampleDeltas() {
return sampleDeltas;
}
}