com.drew.metadata.mp4.boxes.TimeToSampleBox Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of metadata-extractor Show documentation

Java library for extracting EXIF, IPTC, XMP, ICC and other metadata from image and video files.

There is a newer version: 2.19.0

/*
 * Copyright 2002-2019 Drew Noakes and contributors
 *
 *    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.
 *
 * More information about this project is available at:
 *
 *    https://drewnoakes.com/code/exif/
 *    https://github.com/drewnoakes/metadata-extractor
 */
package com.drew.metadata.mp4.boxes;

import com.drew.lang.SequentialReader;
import com.drew.metadata.mp4.Mp4Context;
import com.drew.metadata.mp4.media.Mp4SoundDirectory;
import com.drew.metadata.mp4.media.Mp4VideoDirectory;

import java.io.IOException;
import java.util.ArrayList;

/**
 * ISO/IED 14496-12:2015 pg.37
 */
public class TimeToSampleBox extends FullBox
{
    private long entryCount;
    private ArrayList entries;

    public TimeToSampleBox(SequentialReader reader, Box box) throws IOException
    {
        super(reader, box);

        entryCount = reader.getUInt32();
        entries = new ArrayList();
        for (int i = 0; i < entryCount; i++) {
            entries.add(new EntryCount(reader.getUInt32(), reader.getUInt32()));
        }
    }

    public void addMetadata(Mp4VideoDirectory directory, Mp4Context context)
    {
        float sampleCount = 0;

        for (EntryCount ec : entries) {
            sampleCount += ec.sampleCount;
        }

        float frameRate = (float) context.timeScale/((float) context.duration / sampleCount);

        directory.setFloat(Mp4VideoDirectory.TAG_FRAME_RATE, frameRate);
    }

    public void addMetadata(Mp4SoundDirectory directory, Mp4Context context)
    {
        directory.setDouble(Mp4SoundDirectory.TAG_AUDIO_SAMPLE_RATE, context.timeScale);
    }

    static class EntryCount
    {
        long sampleCount;
        long sampleDelta;

        public EntryCount(long sampleCount, long sampleDelta)
        {
            this.sampleCount = sampleCount;
            this.sampleDelta = sampleDelta;
        }
    }
}