001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.gui.layer.imagery;
003
004import java.awt.Rectangle;
005import java.awt.RenderingHints;
006import java.awt.geom.Point2D;
007import java.awt.geom.Rectangle2D;
008import java.awt.image.BufferedImage;
009import java.awt.image.BufferedImageOp;
010import java.awt.image.ColorModel;
011import java.awt.image.DataBuffer;
012import java.awt.image.DataBufferByte;
013import java.awt.image.IndexColorModel;
014import java.util.Objects;
015import java.util.Optional;
016import java.util.function.Consumer;
017
018import org.openstreetmap.josm.tools.Logging;
019
020/**
021 * Colorful filter.
022 * @since 11914 (extracted from ColorfulImageProcessor)
023 */
024public class ColorfulFilter implements BufferedImageOp {
025    private static final double LUMINOSITY_RED = .21d;
026    private static final double LUMINOSITY_GREEN = .72d;
027    private static final double LUMINOSITY_BLUE = .07d;
028    private final double colorfulness;
029
030    /**
031     * Create a new colorful filter.
032     * @param colorfulness The colorfulness as defined in the {@link ColorfulImageProcessor} class.
033     */
034    ColorfulFilter(double colorfulness) {
035        this.colorfulness = colorfulness;
036    }
037
038    @Override
039    public BufferedImage filter(BufferedImage src, BufferedImage dst) {
040        if (src.getWidth() == 0 || src.getHeight() == 0) {
041            return src;
042        }
043
044        int type = src.getType();
045
046        switch (type) {
047        case BufferedImage.TYPE_BYTE_INDEXED:
048        case BufferedImage.TYPE_3BYTE_BGR:
049        case BufferedImage.TYPE_4BYTE_ABGR:
050        case BufferedImage.TYPE_4BYTE_ABGR_PRE:
051        case BufferedImage.TYPE_INT_ARGB:
052        case BufferedImage.TYPE_INT_ARGB_PRE:
053
054            BufferedImage dest = Optional.ofNullable(dst).orElseGet(() -> createCompatibleDestImage(src, null));
055
056            if (type == BufferedImage.TYPE_BYTE_INDEXED) {
057                try {
058                    return filterIndexed(src, dest);
059                } catch (IllegalArgumentException ex) {
060                    Logging.warn(ex);
061                    break;
062                }
063            }
064
065            DataBuffer srcBuffer = src.getRaster().getDataBuffer();
066            DataBuffer destBuffer = dest.getRaster().getDataBuffer();
067            if (!(srcBuffer instanceof DataBufferByte) || !(destBuffer instanceof DataBufferByte)) {
068                Logging.trace("Images do not use DataBufferByte. Filtering RGB values instead.");
069                break;
070            }
071
072            if (type != dest.getType()) {
073                Logging.trace("Src / Dest differ in type (" + type + '/' + dest.getType() + "). Filtering RGB values instead.");
074                break;
075            }
076
077            int redOffset;
078            int greenOffset;
079            int blueOffset;
080            int alphaOffset = 0;
081            switch (type) {
082            case BufferedImage.TYPE_3BYTE_BGR:
083                blueOffset = 0;
084                greenOffset = 1;
085                redOffset = 2;
086                break;
087            case BufferedImage.TYPE_4BYTE_ABGR:
088            case BufferedImage.TYPE_4BYTE_ABGR_PRE:
089                blueOffset = 1;
090                greenOffset = 2;
091                redOffset = 3;
092                break;
093            case BufferedImage.TYPE_INT_ARGB:
094            case BufferedImage.TYPE_INT_ARGB_PRE:
095                redOffset = 0;
096                greenOffset = 1;
097                blueOffset = 2;
098                alphaOffset = 3;
099                break;
100            default:
101                return doFilterRGB(src);
102            }
103
104            doFilter((DataBufferByte) srcBuffer, (DataBufferByte) destBuffer, redOffset, greenOffset, blueOffset,
105                    alphaOffset, src.getAlphaRaster() != null);
106            return dest;
107        }
108
109        return doFilterRGB(src);
110    }
111
112    /**
113     * Fast alternative for indexed images: We can change the palette here.
114     * @param src The source image
115     * @param dest The image to copy the source to
116     * @return The image.
117     */
118    private BufferedImage filterIndexed(BufferedImage src, BufferedImage dest) {
119        Objects.requireNonNull(dest, "dst needs to be non null");
120        if (src.getType() != BufferedImage.TYPE_BYTE_INDEXED) {
121            throw new IllegalArgumentException("Source must be of type TYPE_BYTE_INDEXED");
122        }
123        if (dest.getType() != BufferedImage.TYPE_BYTE_INDEXED) {
124            throw new IllegalArgumentException("Destination must be of type TYPE_BYTE_INDEXED");
125        }
126        if (!(src.getColorModel() instanceof IndexColorModel)) {
127            throw new IllegalArgumentException("Expecting an IndexColorModel for a image of type TYPE_BYTE_INDEXED");
128        }
129        src.copyData(dest.getRaster());
130
131        IndexColorModel model = (IndexColorModel) src.getColorModel();
132        int size = model.getMapSize();
133        byte[] red = getIndexColorModelData(size, model::getReds);
134        byte[] green = getIndexColorModelData(size, model::getGreens);
135        byte[] blue = getIndexColorModelData(size, model::getBlues);
136        byte[] alphas = getIndexColorModelData(size, model::getAlphas);
137
138        for (int i = 0; i < size; i++) {
139            int r = red[i] & 0xff;
140            int g = green[i] & 0xff;
141            int b = blue[i] & 0xff;
142            double luminosity = r * LUMINOSITY_RED + g * LUMINOSITY_GREEN + b * LUMINOSITY_BLUE;
143            red[i] = mix(r, luminosity);
144            green[i] = mix(g, luminosity);
145            blue[i] = mix(b, luminosity);
146        }
147
148        IndexColorModel dstModel = new IndexColorModel(model.getPixelSize(), model.getMapSize(), red, green, blue, alphas);
149        return new BufferedImage(dstModel, dest.getRaster(), dest.isAlphaPremultiplied(), null);
150    }
151
152    private static byte[] getIndexColorModelData(int size, Consumer<byte[]> consumer) {
153        byte[] data = new byte[size];
154        consumer.accept(data);
155        return data;
156    }
157
158    private void doFilter(DataBufferByte src, DataBufferByte dest, int redOffset, int greenOffset, int blueOffset,
159            int alphaOffset, boolean hasAlpha) {
160        byte[] srcPixels = src.getData();
161        byte[] destPixels = dest.getData();
162        if (srcPixels.length != destPixels.length) {
163            Logging.trace("Cannot apply color filter: Source/Dest lengths differ.");
164            return;
165        }
166        int entries = hasAlpha ? 4 : 3;
167        for (int i = 0; i < srcPixels.length; i += entries) {
168            int r = srcPixels[i + redOffset] & 0xff;
169            int g = srcPixels[i + greenOffset] & 0xff;
170            int b = srcPixels[i + blueOffset] & 0xff;
171            double luminosity = r * LUMINOSITY_RED + g * LUMINOSITY_GREEN + b * LUMINOSITY_BLUE;
172            destPixels[i + redOffset] = mix(r, luminosity);
173            destPixels[i + greenOffset] = mix(g, luminosity);
174            destPixels[i + blueOffset] = mix(b, luminosity);
175            if (hasAlpha) {
176                destPixels[i + alphaOffset] = srcPixels[i + alphaOffset];
177            }
178        }
179    }
180
181    private BufferedImage doFilterRGB(BufferedImage src) {
182        int w = src.getWidth();
183        int h = src.getHeight();
184
185        int[] arr = src.getRGB(0, 0, w, h, null, 0, w);
186        int argb, a, r, g, b;
187        double luminosity;
188
189        for (int i = 0; i < arr.length; i++) {
190            argb = arr[i];
191            a = (argb >> 24) & 0xff;
192            r = (argb >> 16) & 0xff;
193            g = (argb >> 8) & 0xff;
194            b = argb & 0xff;
195            luminosity = r * LUMINOSITY_RED + g * LUMINOSITY_GREEN + b * LUMINOSITY_BLUE;
196            r = mixInt(r, luminosity);
197            g = mixInt(g, luminosity);
198            b = mixInt(b, luminosity);
199            argb = a;
200            argb = (argb << 8) + r;
201            argb = (argb << 8) + g;
202            argb = (argb << 8) + b;
203            arr[i] = argb;
204        }
205
206        BufferedImage dest = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);
207        dest.setRGB(0, 0, w, h, arr, 0, w);
208        return dest;
209    }
210
211    private int mixInt(int color, double luminosity) {
212        int val = (int) (colorfulness * color + (1 - colorfulness) * luminosity);
213        if (val < 0) {
214            return 0;
215        } else if (val > 0xff) {
216            return 0xff;
217        } else {
218            return val;
219        }
220    }
221
222    private byte mix(int color, double luminosity) {
223        return (byte) mixInt(color, luminosity);
224    }
225
226    @Override
227    public Rectangle2D getBounds2D(BufferedImage src) {
228        return new Rectangle(src.getWidth(), src.getHeight());
229    }
230
231    @Override
232    public BufferedImage createCompatibleDestImage(BufferedImage src, ColorModel destCM) {
233        return new BufferedImage(src.getWidth(), src.getHeight(), src.getType());
234    }
235
236    @Override
237    public Point2D getPoint2D(Point2D srcPt, Point2D dstPt) {
238        return (Point2D) srcPt.clone();
239    }
240
241    @Override
242    public RenderingHints getRenderingHints() {
243        return null;
244    }
245}