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.imaging.png;
  
  import com.drew.lang.SequentialByteArrayReader;
  import com.drew.lang.SequentialReader;
  import com.drew.lang.annotations.NotNull;
  
  import java.io.IOException;
  
  /**
   * @author Drew Noakes https://drewnoakes.com
   */
  public class PngHeader
  {
      private final int _imageWidth;
      private final int _imageHeight;
      private final byte _bitsPerSample;
      @NotNull
      private final PngColorType _colorType;
      private final byte _compressionType;
      private final byte _filterMethod;
      private final byte _interlaceMethod;
  
      public PngHeader(@NotNull byte[] bytes) throws PngProcessingException
      {
          if (bytes.length != 13) {
              throw new PngProcessingException("PNG header chunk must have 13 data bytes");
          }
          SequentialReader reader = new SequentialByteArrayReader(bytes);
          try {
              _imageWidth = reader.getInt32();
              _imageHeight = reader.getInt32();
              _bitsPerSample = reader.getInt8();
              byte colorTypeNumber = reader.getInt8();
              _colorType = PngColorType.fromNumericValue(colorTypeNumber);
              _compressionType = reader.getInt8();
              _filterMethod = reader.getInt8();
              _interlaceMethod = reader.getInt8();
          } catch (IOException e) {
              // Should never happen
              throw new PngProcessingException(e);
          }
      }
  
      public int getImageWidth()
      {
          return _imageWidth;
      }
  
      public int getImageHeight()
      {
          return _imageHeight;
      }
  
      public byte getBitsPerSample()
      {
          return _bitsPerSample;
      }
  
      @NotNull
      public PngColorType getColorType()
      {
          return _colorType;
      }
  
      public byte getCompressionType()
      {
          return _compressionType;
      }
  
      public byte getFilterMethod()
      {
          return _filterMethod;
      }
  
      public byte getInterlaceMethod()
      {
          return _interlaceMethod;
      }
  }
  