# PDDeviceCMYK.java

    /*
     * Licensed to the Apache Software Foundation (ASF) under one or more
     * contributor license agreements.  See the NOTICE file distributed with
     * this work for additional information regarding copyright ownership.
     * The ASF licenses this file to You 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.
     */
    package org.apache.pdfbox.pdmodel.graphics.color;

    import java.util.Arrays;

    import org.apache.pdfbox.cos.COSName;

    import java.awt.color.ColorSpace;
    import java.awt.color.ICC_ColorSpace;
    import java.awt.color.ICC_Profile;
    import java.awt.image.BufferedImage;
    import java.awt.image.WritableRaster;
    import java.io.BufferedInputStream;
    import java.io.IOException;

    import java.io.InputStream;

    /**
     * Allows colors to be specified according to the subtractive CMYK (cyan, magenta, yellow, black)
     * model typical of printers and other paper-based output devices.
     *
     * @author John Hewson
     * @author Ben Litchfield
     */
    public class PDDeviceCMYK extends PDDeviceColorSpace
    {
        /**  The single instance of this class. */
        public static PDDeviceCMYK INSTANCE;
        static
        {
            INSTANCE = new PDDeviceCMYK();
        }

        private final PDColor initialColor = new PDColor(new float[] { 0, 0, 0, 1 }, this);
        private ICC_ColorSpace awtColorSpace;
        private volatile boolean initDone = false;
        private boolean usePureJavaCMYKConversion = false;

        protected PDDeviceCMYK()
        {
        }

        /**
         * Lazy load the ICC profile, because it's slow.
         */
        protected void init() throws IOException
        {
            // no need to synchronize this check as it is atomic
            if (initDone)
            {
                return;
            }
            synchronized (this)
            {
                // we might have been waiting for another thread, so check again
                if (initDone)
                {
                    return;
                }
                // loads the ICC color profile for CMYK
                ICC_Profile iccProfile = getICCProfile();
                if (iccProfile == null)
                {
                    throw new IOException("Default CMYK color profile could not be loaded");
                }
                awtColorSpace = new ICC_ColorSpace(iccProfile);

                // there is a JVM bug which results in a CMMException which appears to be a race
                // condition caused by lazy initialization of the color transform, so we perform
                // an initial color conversion while we're still in a static context, see PDFBOX-2184
                awtColorSpace.toRGB(new float[] { 0, 0, 0, 0 });
                usePureJavaCMYKConversion = System
                        .getProperty("org.apache.pdfbox.rendering.UsePureJavaCMYKConversion") != null;

                // Assignment to volatile must be the LAST statement in this block!
                initDone = true;
            }
        }

        protected ICC_Profile getICCProfile() throws IOException
        {
            // Adobe Acrobat uses "U.S. Web Coated (SWOP) v2" as the default
            // CMYK profile, however it is not available under an open license.
            // Instead, the "ISO Coated v2 300% (basICColor)" is used, which
            // is an open alternative to the "ISO Coated v2 300% (ECI)" profile.

            String resourceName = "/org/apache/pdfbox/resources/icc/ISOcoated_v2_300_bas.icc";
            InputStream resourceAsStream = PDDeviceCMYK.class.getResourceAsStream(resourceName);
            if (resourceAsStream == null)
            {
                throw new IOException("resource '" + resourceName + "' not found");
            }
            try (InputStream is = new BufferedInputStream(resourceAsStream))
            {
                return ICC_Profile.getInstance(is);
            }
        }

        @Override
        public String getName()
        {
            return COSName.DEVICECMYK.getName();
        }

        @Override
        public int getNumberOfComponents()
        {
            return 4;
        }

        @Override
        public float[] getDefaultDecode(int bitsPerComponent)
        {
            return new float[] { 0, 1, 0, 1, 0, 1, 0, 1 };
        }

        @Override
        public PDColor getInitialColor()
        {
            return initialColor;
        }

        @Override
        public float[] toRGB(float[] value) throws IOException
        {
            init();
            return awtColorSpace.toRGB(value);
        }

        @Override
        public BufferedImage toRawImage(WritableRaster raster) throws IOException
        {
            // Device CMYK is not specified, as its the colors of whatever device you use.
            // The user should fallback to the RGB image
            return null;
        }

        @Override
        public BufferedImage toRGBImage(WritableRaster raster) throws IOException
        {
            init();
            return toRGBImageAWT(raster, awtColorSpace);
        }

        @Override
        protected BufferedImage toRGBImageAWT(WritableRaster raster, ColorSpace colorSpace)
        {
            if (usePureJavaCMYKConversion)
            {
                BufferedImage dest = new BufferedImage(raster.getWidth(), raster.getHeight(),
                        BufferedImage.TYPE_INT_RGB);
                ColorSpace destCS = dest.getColorModel().getColorSpace();
                WritableRaster destRaster = dest.getRaster();
                float[] srcValues = new float[4];
                float[] lastValues = new float[] { -1.0f, -1.0f, -1.0f, -1.0f };
                float[] destValues = new float[3];
                int startX = raster.getMinX();
                int startY = raster.getMinY();
                int endX = raster.getWidth() + startX;
                int endY = raster.getHeight() + startY;
                for (int x = startX; x < endX; x++)
                {
                    for (int y = startY; y < endY; y++)
                    {
                        raster.getPixel(x, y, srcValues);
                        // check if the last value can be reused
                        if (!Arrays.equals(lastValues, srcValues))
                        {
                            lastValues[0] = srcValues[0];
                            srcValues[0] = srcValues[0] / 255f;

                            lastValues[1] = srcValues[1];
                            srcValues[1] = srcValues[1] / 255f;

                            lastValues[2] = srcValues[2];
                            srcValues[2] = srcValues[2] / 255f;

                            lastValues[3] = srcValues[3];
                            srcValues[3] = srcValues[3] / 255f;

                            // use CIEXYZ as intermediate format to optimize the color conversion
                            destValues = destCS.fromCIEXYZ(colorSpace.toCIEXYZ(srcValues));
                            for (int k = 0; k < destValues.length; k++)
                            {
                                destValues[k] = destValues[k] * 255f;
                            }
                        }
                        destRaster.setPixel(x, y, destValues);
                    }
                }
                return dest;
            }
            else
            {
                return super.toRGBImageAWT(raster, colorSpace);
            }
        }
    }