content: /*
   * 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
   *
   *        https://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.mov.atoms;
  
  import com.drew.lang.SequentialReader;
  import com.drew.metadata.mov.QuickTimeDirectory;
  import com.drew.metadata.mp4.Mp4Directory;
  
  import java.io.IOException;
  
  /**
   * Extracts rotation information only
   *
   * https://developer.apple.com/library/content/documentation/QuickTime/QTFF/QTFFChap2/qtff2.html#//apple_ref/doc/uid/TP40000939-CH204-SW34
   *
   * @author Ferenc Balogh
   */
  public class TrackHeaderAtom extends FullAtom {
      int[] matrix = new int[9];
      long width;
      long height;
  
      public TrackHeaderAtom(SequentialReader reader, Atom atom) throws IOException {
          super(reader, atom);
  
          if (version == 1) {
              reader.skip(48);
          } else {
              reader.skip(36);
          }
  
          for (int i = 0; i < 9; i++) {
              matrix[i] = reader.getInt32();
          }
          width = reader.getInt32();
          height = reader.getInt32();
      }
  
      public void addMetadata(QuickTimeDirectory directory) {
          if (width != 0 && height != 0 && directory.getDoubleObject(Mp4Directory.TAG_ROTATION) == null) {
              double x = matrix[1] + matrix[4];
              double y = matrix[0] + matrix[3];
              double theta = Math.atan2(y, x);
              double degree = Math.toDegrees(theta) - 45;
              directory.setDouble(QuickTimeDirectory.TAG_ROTATION, degree);
          }
      }
  }
  