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/*
* Copyright (C) 2012 The Android Open Source Project
*
* 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.
*/
// Modified example based on mp4parser google code open source project.
// http://code.google.com/p/mp4parser/source/browse/trunk/examples/src/main/java/com/googlecode/mp4parser/ShortenExample.java
package com.android.gallery3d.app;
import com.coremedia.iso.IsoFile;
import com.coremedia.iso.boxes.TimeToSampleBox;
import com.googlecode.mp4parser.authoring.Movie;
import com.googlecode.mp4parser.authoring.Track;
import com.googlecode.mp4parser.authoring.builder.DefaultMp4Builder;
import com.googlecode.mp4parser.authoring.container.mp4.MovieCreator;
import com.googlecode.mp4parser.authoring.tracks.CroppedTrack;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.channels.FileChannel;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;
/**
* Shortens/Crops a track
*/
public class TrimVideoUtils {
public static void startTrim(File src, File dst, int startMs, int endMs) throws IOException {
RandomAccessFile randomAccessFile = new RandomAccessFile(src, "r");
Movie movie = MovieCreator.build(randomAccessFile.getChannel());
// remove all tracks we will create new tracks from the old
List<Track> tracks = movie.getTracks();
movie.setTracks(new LinkedList<Track>());
double startTime = startMs/1000;
double endTime = endMs/1000;
boolean timeCorrected = false;
// Here we try to find a track that has sync samples. Since we can only start decoding
// at such a sample we SHOULD make sure that the start of the new fragment is exactly
// such a frame
for (Track track : tracks) {
if (track.getSyncSamples() != null && track.getSyncSamples().length > 0) {
if (timeCorrected) {
// This exception here could be a false positive in case we have multiple tracks
// with sync samples at exactly the same positions. E.g. a single movie containing
// multiple qualities of the same video (Microsoft Smooth Streaming file)
throw new RuntimeException("The startTime has already been corrected by another track with SyncSample. Not Supported.");
}
startTime = correctTimeToSyncSample(track, startTime, false);
endTime = correctTimeToSyncSample(track, endTime, true);
timeCorrected = true;
}
}
for (Track track : tracks) {
long currentSample = 0;
double currentTime = 0;
long startSample = -1;
long endSample = -1;
for (int i = 0; i < track.getDecodingTimeEntries().size(); i++) {
TimeToSampleBox.Entry entry = track.getDecodingTimeEntries().get(i);
for (int j = 0; j < entry.getCount(); j++) {
// entry.getDelta() is the amount of time the current sample covers.
if (currentTime <= startTime) {
// current sample is still before the new starttime
startSample = currentSample;
}
if (currentTime <= endTime) {
// current sample is after the new start time and still before the new endtime
endSample = currentSample;
} else {
// current sample is after the end of the cropped video
break;
}
currentTime += (double) entry.getDelta() / (double) track.getTrackMetaData().getTimescale();
currentSample++;
}
}
movie.addTrack(new CroppedTrack(track, startSample, endSample));
}
IsoFile out = new DefaultMp4Builder().build(movie);
if (!dst.exists()) {
dst.createNewFile();
}
FileOutputStream fos = new FileOutputStream(dst);
FileChannel fc = fos.getChannel();
out.getBox(fc); // This one build up the memory.
fc.close();
fos.close();
randomAccessFile.close();
}
protected static long getDuration(Track track) {
long duration = 0;
for (TimeToSampleBox.Entry entry : track.getDecodingTimeEntries()) {
duration += entry.getCount() * entry.getDelta();
}
return duration;
}
private static double correctTimeToSyncSample(Track track, double cutHere, boolean next) {
double[] timeOfSyncSamples = new double[track.getSyncSamples().length];
long currentSample = 0;
double currentTime = 0;
for (int i = 0; i < track.getDecodingTimeEntries().size(); i++) {
TimeToSampleBox.Entry entry = track.getDecodingTimeEntries().get(i);
for (int j = 0; j < entry.getCount(); j++) {
if (Arrays.binarySearch(track.getSyncSamples(), currentSample + 1) >= 0) {
// samples always start with 1 but we start with zero therefore +1
timeOfSyncSamples[Arrays.binarySearch(track.getSyncSamples(), currentSample + 1)] = currentTime;
}
currentTime += (double) entry.getDelta() / (double) track.getTrackMetaData().getTimescale();
currentSample++;
}
}
double previous = 0;
for (double timeOfSyncSample : timeOfSyncSamples) {
if (timeOfSyncSample > cutHere) {
if (next) {
return timeOfSyncSample;
} else {
return previous;
}
}
previous = timeOfSyncSample;
}
return timeOfSyncSamples[timeOfSyncSamples.length - 1];
}
}
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