001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.imaging.formats.png.chunks;
018
019import static org.apache.commons.imaging.common.BinaryFunctions.read4Bytes;
020import static org.apache.commons.imaging.common.BinaryFunctions.readByte;
021
022import java.io.ByteArrayInputStream;
023import java.io.IOException;
024
025public final class PngChunkPhys extends PngChunk {
026
027    private final int pixelsPerUnitXAxis;
028    private final int pixelsPerUnitYAxis;
029    private final int unitSpecifier;
030
031    public PngChunkPhys(final int length, final int chunkType, final int crc, final byte[] bytes) throws IOException {
032        super(length, chunkType, crc, bytes);
033        final ByteArrayInputStream is = new ByteArrayInputStream(bytes);
034        pixelsPerUnitXAxis = read4Bytes("PixelsPerUnitXAxis", is, "Not a Valid PNG File: pHYs Corrupt", getByteOrder());
035        pixelsPerUnitYAxis = read4Bytes("PixelsPerUnitYAxis", is, "Not a Valid PNG File: pHYs Corrupt", getByteOrder());
036        unitSpecifier = readByte("Unit specifier", is, "Not a Valid PNG File: pHYs Corrupt");
037    }
038
039    public int getPixelsPerUnitXAxis() {
040        return pixelsPerUnitXAxis;
041    }
042
043    public int getPixelsPerUnitYAxis() {
044        return pixelsPerUnitYAxis;
045    }
046
047    public int getUnitSpecifier() {
048        return unitSpecifier;
049    }
050
051}