    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.transparencyfilters;
    018
    019import static org.apache.commons.imaging.common.BinaryFunctions.read2Bytes;
    020
    021import java.io.ByteArrayInputStream;
    022import java.io.IOException;
    023
    024import org.apache.commons.imaging.ImagingException;
    025
    026public final class TransparencyFilterTrueColor extends AbstractTransparencyFilter {
    027    private final int transparentColor;
    028
    029    public TransparencyFilterTrueColor(final byte[] bytes) throws IOException {
    030        super(bytes);
    031
    032        final ByteArrayInputStream is = new ByteArrayInputStream(bytes);
    033        final int transparentRed = read2Bytes("transparentRed", is, "tRNS: Missing transparentColor", getByteOrder());
    034        final int transparentGreen = read2Bytes("transparentGreen", is, "tRNS: Missing transparentColor", getByteOrder());
    035        final int transparentBlue = read2Bytes("transparentBlue", is, "tRNS: Missing transparentColor", getByteOrder());
    036
    037        transparentColor = (0xff & transparentRed) << 16 | (0xff & transparentGreen) << 8 | (0xff & transparentBlue) << 0;
    038
    039    }
    040
    041    @Override
    042    public int filter(final int rgb, final int sample) throws ImagingException, IOException {
    043        if ((0x00ffffff & rgb) == transparentColor) {
    044            return 0x00;
    045        }
    046
    047        return rgb;
    048    }
    049}