com.googlecode.mp4parser.authoring.builder.DefaultFragmenterImpl Maven / Gradle / Ivy
/*
* Copyright 2012 Sebastian Annies, 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.googlecode.mp4parser.authoring.builder;
import com.googlecode.mp4parser.authoring.Track;
import com.googlecode.mp4parser.util.Mp4Arrays;
import java.util.Arrays;
/**
* Finds start samples within a given track so that:
*
* - Each segment is at least
fragmentLength
seconds long
* - The last segment might be almost twice the size of the rest
*
*/
public class DefaultFragmenterImpl implements Fragmenter {
private double fragmentLength = 2.0D;
public DefaultFragmenterImpl(double fragmentLength) {
this.fragmentLength = fragmentLength;
}
public long[] sampleNumbers(Track track) {
long[] segmentStartSamples = new long[]{1L};
long[] sampleDurations = track.getSampleDurations();
long[] syncSamples = track.getSyncSamples();
long timescale = track.getTrackMetaData().getTimescale();
double time = 0.0D;
for (int i = 0; i < sampleDurations.length; ++i) {
time += (double) sampleDurations[i] / (double) timescale;
if (time >= this.fragmentLength && (syncSamples == null || Arrays.binarySearch(syncSamples, (long) (i + 1)) >= 0)) {
if (i > 0) {
segmentStartSamples = Mp4Arrays.copyOfAndAppend(segmentStartSamples, (long) (i + 1));
}
time = 0.0D;
}
}
// In case the last Fragment is shorter: make the previous one a bigger and omit the small one
if (time < fragmentLength && segmentStartSamples.length > 1) {
long[] nuSegmentStartSamples = new long[segmentStartSamples.length - 1];
System.arraycopy(segmentStartSamples, 0, nuSegmentStartSamples, 0, segmentStartSamples.length - 1);
segmentStartSamples = nuSegmentStartSamples;
}
return segmentStartSamples;
}
}