TMI-70: BMP image metadata + bonus listener delegation.

common/common-io/src/main/java/com/twelvemonkeys/xml/XMLSerializer.java

@@ -459,6 +459,16 @@ public class XMLSerializer {
             pOut.print(pNode.getTagName());
             pOut.println(">");
         }
+        else if (pNode.getNodeValue() != null) {
+            // NOTE: This is NOT AS SPECIFIED, but we do this to support
+            // the weirdness that is the javax.imageio.metadata.IIOMetadataNode.
+            // According to the spec, the nodeValue of an Element is null.
+            pOut.print(">");
+            pOut.print(pNode.getNodeValue());
+            pOut.print("</");
+            pOut.print(pNode.getTagName());
+            pOut.println(">");
+        }
         else {
             pOut.println("/>");
         }

imageio/imageio-bmp/src/main/java/com/twelvemonkeys/imageio/plugins/bmp/BMPImageReader.java

@@ -32,11 +32,15 @@ import com.twelvemonkeys.imageio.ImageReaderBase;
 import com.twelvemonkeys.imageio.stream.SubImageInputStream;
 import com.twelvemonkeys.imageio.util.IIOUtil;
 import com.twelvemonkeys.imageio.util.IndexedImageTypeSpecifier;
+import com.twelvemonkeys.imageio.util.ProgressListenerBase;
 import com.twelvemonkeys.io.LittleEndianDataInputStream;
 import com.twelvemonkeys.io.enc.DecoderStream;
+import com.twelvemonkeys.lang.Validate;
 import com.twelvemonkeys.xml.XMLSerializer;
 
 import javax.imageio.*;
+import javax.imageio.event.IIOReadUpdateListener;
+import javax.imageio.event.IIOReadWarningListener;
 import javax.imageio.metadata.IIOMetadata;
 import javax.imageio.metadata.IIOMetadataFormatImpl;
 import javax.imageio.spi.ImageReaderSpi;
@@ -45,7 +49,6 @@ import java.awt.*;
 import java.awt.color.ColorSpace;
 import java.awt.image.*;
 import java.io.DataInput;
-import java.io.EOFException;
 import java.io.File;
 import java.io.IOException;
 import java.nio.ByteOrder;
@@ -58,15 +61,16 @@ import java.util.Iterator;
  * @author <a href="mailto:harald.kuhr@gmail.com">Harald Kuhr</a>
  * @author last modified by $Author: haraldk$
  * @version $Id: CURImageReader.java,v 1.0 Apr 20, 2009 11:54:28 AM haraldk Exp$
- *
  * @see com.twelvemonkeys.imageio.plugins.bmp.ICOImageReader
  */
 public final class BMPImageReader extends ImageReaderBase {
     private long pixelOffset;
     private DIBHeader header;
+    private int[] colors;
+    private IndexColorModel colorMap;
 
-    private transient ImageReader jpegReaderDelegate;
+    private ImageReader jpegReaderDelegate;
-    private transient ImageReader pngReaderDelegate;
+    private ImageReader pngReaderDelegate;
 
     public BMPImageReader() {
         super(new BMPImageReaderSpi());
@@ -80,6 +84,8 @@ public final class BMPImageReader extends ImageReaderBase {
     protected void resetMembers() {
         pixelOffset = 0;
         header = null;
+        colors = null;
+        colorMap = null;
 
         if (pngReaderDelegate != null) {
             pngReaderDelegate.dispose();
@@ -121,6 +127,53 @@ public final class BMPImageReader extends ImageReaderBase {
         }
     }
 
+    private IndexColorModel readColorMap() throws IOException {
+        readHeader();
+
+        if (colors == null) {
+            if (header.getBitCount() > 8 && header.colorsUsed == 0) {
+                // RGB without color map
+                colors = new int[0];
+            }
+            else {
+                int offset = DIB.BMP_FILE_HEADER_SIZE + header.getSize();
+                if (offset != imageInput.getStreamPosition()) {
+                    imageInput.seek(offset);
+                }
+
+                if (header.getSize() == DIB.BITMAP_CORE_HEADER_SIZE) {
+                    colors = new int[Math.min(header.getColorsUsed(), (int) (pixelOffset - DIB.BMP_FILE_HEADER_SIZE - header.getSize()) / 3)];
+
+                    // Byte triplets in BGR form
+                    for (int i = 0; i < colors.length; i++) {
+                        int b = imageInput.readUnsignedByte();
+                        int g = imageInput.readUnsignedByte();
+                        int r = imageInput.readUnsignedByte();
+                        colors[i] = r << 16 | g << 8 | b | 0xff000000;
+                    }
+                }
+                else {
+                    colors = new int[Math.min(header.getColorsUsed(), (int) (pixelOffset - DIB.BMP_FILE_HEADER_SIZE - header.getSize()) / 4)];
+
+                    // Byte quadruples in BGRa (or little-endian ints in aRGB) form, where a is "Reserved"
+                    for (int i = 0; i < colors.length; i++) {
+                        colors[i] = imageInput.readInt() & 0x00ffffff | 0xff000000;
+                    }
+                }
+
+                // There might be more entries in the color map, but we ignore these for reading
+                int mapSize = Math.min(colors.length, 1 << header.getBitCount());
+
+                // Compute bits for > 8 bits (used only for meta data)
+                int bits = header.getBitCount() <= 8 ? header.getBitCount() : mapSize <= 256 ? 8 : 16;
+
+                colorMap = new IndexColorModel(bits, mapSize, colors, 0, false, Transparency.OPAQUE, DataBuffer.TYPE_BYTE);
+            }
+        }
+
+        return colorMap;
+    }
+
     @Override
     public int getWidth(int pImageIndex) throws IOException {
         checkBounds(pImageIndex);
@@ -143,40 +196,6 @@ public final class BMPImageReader extends ImageReaderBase {
         return Arrays.asList(getRawImageType(pImageIndex)).iterator();
     }
 
-    private void readColorMap(final BitmapIndexed pBitmap) throws IOException {
-        int offset = DIB.BMP_FILE_HEADER_SIZE + header.getSize();
-        if (offset != imageInput.getStreamPosition()) {
-            imageInput.seek(offset);
-        }
-
-        switch (header.getCompression()) {
-            case DIB.COMPRESSION_RGB:
-            case DIB.COMPRESSION_RLE4:
-            case DIB.COMPRESSION_RLE8:
-                break;
-            default:
-                throw new IIOException("Unsupported compression for palette: " + header.getCompression());
-        }
-
-        int colorCount = pBitmap.getColorCount();
-
-        if (header.getSize() == DIB.BITMAP_CORE_HEADER_SIZE) {
-            // Byte triplets in BGR form
-            for (int i = 0; i < colorCount; i++) {
-                int b = imageInput.readUnsignedByte();
-                int g = imageInput.readUnsignedByte();
-                int r = imageInput.readUnsignedByte();
-                pBitmap.colors[i] = r << 16 | g << 8 | b | 0xff000000;
-            }
-        }
-        else {
-            // Byte quadruples in BGRa (or ints in aRGB) form (where a is "Reserved")
-            for (int i = 0; i < colorCount; i++) {
-                pBitmap.colors[i] = (imageInput.readInt() & 0xffffff) | 0xff000000;
-            }
-        }
-    }
-
     @Override
     public ImageTypeSpecifier getRawImageType(int pImageIndex) throws IOException {
         checkBounds(pImageIndex);
@@ -190,22 +209,17 @@ public final class BMPImageReader extends ImageReaderBase {
             case 2:
             case 4:
             case 8:
-                // TODO: Get rid of the fake DirectoryEntry and support color maps directly
+                return IndexedImageTypeSpecifier.createFromIndexColorModel(readColorMap());
-                BitmapIndexed indexed = new BitmapIndexed(new DirectoryEntry() {}, header);
-                readColorMap(indexed);
-                return IndexedImageTypeSpecifier.createFromIndexColorModel(indexed.createColorModel());
 
             case 16:
                 if (header.hasMasks()) {
                     int[] masks = getMasks();
 
-                    return ImageTypeSpecifier.createPacked(ColorSpace.getInstance(ColorSpace.CS_sRGB),
+                    return ImageTypeSpecifier.createPacked(
-                                masks[0],
+                            ColorSpace.getInstance(ColorSpace.CS_sRGB),
-                                masks[1],
+                            masks[0], masks[1], masks[2], masks[3],
-                                masks[2],
+                            DataBuffer.TYPE_USHORT, false
-                                masks[3],
+                    );
-                                DataBuffer.TYPE_USHORT,
-                                false);
                 }
 
                 // Default if no mask is 555
@@ -222,13 +236,11 @@ public final class BMPImageReader extends ImageReaderBase {
                 if (header.hasMasks()) {
                     int[] masks = getMasks();
 
-                    return ImageTypeSpecifier.createPacked(ColorSpace.getInstance(ColorSpace.CS_sRGB),
+                    return ImageTypeSpecifier.createPacked(
-                            masks[0],
+                            ColorSpace.getInstance(ColorSpace.CS_sRGB),
-                            masks[1],
+                            masks[0], masks[1], masks[2], masks[3],
-                            masks[2],
+                            DataBuffer.TYPE_INT, false
-                            masks[3],
+                    );
-                            DataBuffer.TYPE_INT,
-                            false);
                 }
 
                 // Default if no mask
@@ -290,10 +302,18 @@ public final class BMPImageReader extends ImageReaderBase {
         ImageTypeSpecifier rawType = getRawImageType(imageIndex);
         BufferedImage destination = getDestination(param, getImageTypes(imageIndex), width, height);
 
+        ColorModel colorModel = destination.getColorModel();
+        if (colorModel instanceof IndexColorModel && ((IndexColorModel) colorModel).getMapSize() < header.getColorsUsed()) {
+            processWarningOccurred(
+                    String.format("Color map contains more colors than raster allows (%d). Ignoring entries above %d.",
+                            header.getColorsUsed(), ((IndexColorModel) colorModel).getMapSize())
+            );
+        }
+
         // BMP rows are padded to 4 byte boundary
         int rowSizeBytes = ((header.getBitCount() * width + 31) / 32) * 4;
 
-        // Wrap
+        // Wrap input according to compression
         imageInput.seek(pixelOffset);
         DataInput input;
 
@@ -369,17 +389,7 @@ public final class BMPImageReader extends ImageReaderBase {
                 case 8:
                 case 24:
                     byte[] rowDataByte = ((DataBufferByte) rowRaster.getDataBuffer()).getData();
-                    try {
+                    readRowByte(input, height, srcRegion, xSub, ySub, rowDataByte, destRaster, clippedRow, y);
-                        readRowByte(input, height, srcRegion, xSub, ySub, rowDataByte, destRaster, clippedRow, y);
-                    }
-                    catch (IndexOutOfBoundsException ioob) {
-                        System.err.println("IOOB: " + ioob);
-                        System.err.println("y: " + y);
-                    }
-                    catch (EOFException eof) {
-                        System.err.println("EOF: " + eof);
-                        System.err.println("y: " + y);
-                    }
                     break;
 
                 case 16:
@@ -414,9 +424,7 @@ public final class BMPImageReader extends ImageReaderBase {
     }
 
     private BufferedImage readUsingDelegate(final int compression, final ImageReadParam param) throws IOException {
-        ImageReader reader = initReaderDelegate(compression);
+        return initReaderDelegate(compression).read(0, param);
-
-        return reader.read(0, param);
     }
 
     private ImageReader initReaderDelegate(int compression) throws IOException {
@@ -454,12 +462,19 @@ public final class BMPImageReader extends ImageReaderBase {
 
         // Consider looking for specific PNG and JPEG implementations.
         Iterator<ImageReader> readers = ImageIO.getImageReadersByFormatName(format);
+
         if (!readers.hasNext()) {
             throw new IIOException(String.format("Delegate ImageReader for %s format not found", format));
         }
 
         ImageReader reader = readers.next();
 
+        // Install listener
+        ListenerDelegator listenerDelegator = new ListenerDelegator();
+        reader.addIIOReadWarningListener(listenerDelegator);
+        reader.addIIOReadProgressListener(listenerDelegator);
+        reader.addIIOReadUpdateListener(listenerDelegator);
+
         // Cache for later use
         switch (compression) {
             case DIB.COMPRESSION_JPEG:
@@ -503,8 +518,7 @@ public final class BMPImageReader extends ImageReaderBase {
 
         if (header.topDown) {
             destChannel.setDataElements(0, y, srcChannel);
-        }
+        } else {
-        else {
             // Flip into position
             int dstY = (height - 1 - y - srcRegion.y) / ySub;
             destChannel.setDataElements(0, dstY, srcChannel);
@@ -536,8 +550,7 @@ public final class BMPImageReader extends ImageReaderBase {
 
         if (header.topDown) {
             destChannel.setDataElements(0, y, srcChannel);
-        }
+        } else {
-        else {
             // Flip into position
             int dstY = (height - 1 - y - srcRegion.y) / ySub;
             destChannel.setDataElements(0, dstY, srcChannel);
@@ -545,7 +558,7 @@ public final class BMPImageReader extends ImageReaderBase {
     }
 
     private void readRowInt(final DataInput input, final int height, final Rectangle srcRegion, final int xSub, final int ySub,
-                            final int [] rowDataInt, final WritableRaster destChannel, final Raster srcChannel, final int y) throws IOException {
+                            final int[] rowDataInt, final WritableRaster destChannel, final Raster srcChannel, final int y) throws IOException {
         // If subsampled or outside source region, skip entire row
         if (y % ySub != 0 || height - 1 - y < srcRegion.y || height - 1 - y >= srcRegion.y + srcRegion.height) {
             input.skipBytes(rowDataInt.length * 4);
@@ -564,8 +577,7 @@ public final class BMPImageReader extends ImageReaderBase {
 
         if (header.topDown) {
             destChannel.setDataElements(0, y, srcChannel);
-        }
+        } else {
-        else {
             // Flip into position
             int dstY = (height - 1 - y - srcRegion.y) / ySub;
             destChannel.setDataElements(0, dstY, srcChannel);
@@ -577,8 +589,7 @@ public final class BMPImageReader extends ImageReaderBase {
         if (input instanceof ImageInputStream) {
             // Optimization for ImageInputStreams, read all in one go
             ((ImageInputStream) input).readFully(shorts, 0, shorts.length);
-        }
+        } else {
-        else {
             for (int i = 0; i < shorts.length; i++) {
                 shorts[i] = input.readShort();
             }
@@ -590,8 +601,7 @@ public final class BMPImageReader extends ImageReaderBase {
         if (input instanceof ImageInputStream) {
             // Optimization for ImageInputStreams, read all in one go
             ((ImageInputStream) input).readFully(ints, 0, ints.length);
-        }
+        } else {
-        else {
             for (int i = 0; i < ints.length; i++) {
                 ints[i] = input.readInt();
             }
@@ -617,6 +627,31 @@ public final class BMPImageReader extends ImageReaderBase {
         return raster.createWritableChild(rect.x, rect.y, rect.width, rect.height, 0, 0, bands);
     }
 
+    @Override
+    public IIOMetadata getImageMetadata(int imageIndex) throws IOException {
+        readHeader();
+
+        switch (header.getBitCount()) {
+            case 1:
+            case 2:
+            case 4:
+            case 8:
+                readColorMap();
+                break;
+
+            default:
+                if (header.colorsUsed > 0) {
+                    readColorMap();
+                }
+                break;
+        }
+
+        // Why, oh why..? Instead of accepting it's own native format as it should,
+        // The BMPImageWriter only accepts instances of com.sun.imageio.plugins.bmp.BMPMetadata...
+        // TODO: Consider reflectively construct a BMPMetadata and inject fields
+        return new BMPMetadata(header, colors);
+    }
+
     public static void main(String[] args) throws IOException {
         BMPImageReaderSpi provider = new BMPImageReaderSpi();
         BMPImageReader reader = new BMPImageReader(provider);
@@ -656,14 +691,12 @@ public final class BMPImageReader extends ImageReaderBase {
                 if (imageMetadata != null) {
                     new XMLSerializer(System.out, System.getProperty("file.encoding")).serialize(imageMetadata.getAsTree(IIOMetadataFormatImpl.standardMetadataFormatName), false);
                 }
-            }
+            } catch (Throwable t) {
-            catch (Throwable t) {
                 if (args.length > 1) {
                     System.err.println("---");
                     System.err.println("---> " + t.getClass().getSimpleName() + ": " + t.getMessage() + " for " + arg);
                     System.err.println("---");
-                }
+                } else {
-                else {
                     throwAs(RuntimeException.class, t);
                 }
             }
@@ -674,4 +707,79 @@ public final class BMPImageReader extends ImageReaderBase {
     static <T extends Throwable> void throwAs(final Class<T> pType, final Throwable pThrowable) throws T {
         throw (T) pThrowable;
     }
+
+    private class ListenerDelegator extends ProgressListenerBase implements IIOReadUpdateListener, IIOReadWarningListener {
+        @Override
+        public void imageComplete(ImageReader source) {
+            processImageComplete();
+        }
+
+        @Override
+        public void imageProgress(ImageReader source, float percentageDone) {
+            processImageProgress(percentageDone);
+        }
+
+        @Override
+        public void imageStarted(ImageReader source, int imageIndex) {
+            processImageStarted(imageIndex);
+        }
+
+        @Override
+        public void readAborted(ImageReader source) {
+            processReadAborted();
+        }
+
+        @Override
+        public void sequenceComplete(ImageReader source) {
+            processSequenceComplete();
+        }
+
+        @Override
+        public void sequenceStarted(ImageReader source, int minIndex) {
+            processSequenceStarted(minIndex);
+        }
+
+        @Override
+        public void thumbnailComplete(ImageReader source) {
+            processThumbnailComplete();
+        }
+
+        @Override
+        public void thumbnailProgress(ImageReader source, float percentageDone) {
+            processThumbnailProgress(percentageDone);
+        }
+
+        @Override
+        public void thumbnailStarted(ImageReader source, int imageIndex, int thumbnailIndex) {
+            processThumbnailStarted(imageIndex, thumbnailIndex);
+        }
+
+        public void passStarted(ImageReader source, BufferedImage theImage, int pass, int minPass, int maxPass, int minX, int minY, int periodX, int periodY, int[] bands) {
+            processPassStarted(theImage, pass, minPass, maxPass, minX, minY, periodX, periodY, bands);
+        }
+
+        public void imageUpdate(ImageReader source, BufferedImage theImage, int minX, int minY, int width, int height, int periodX, int periodY, int[] bands) {
+            processImageUpdate(theImage, minX, minY, width, height, periodX, periodY, bands);
+        }
+
+        public void passComplete(ImageReader source, BufferedImage theImage) {
+            processPassComplete(theImage);
+        }
+
+        public void thumbnailPassStarted(ImageReader source, BufferedImage theThumbnail, int pass, int minPass, int maxPass, int minX, int minY, int periodX, int periodY, int[] bands) {
+            processThumbnailPassStarted(theThumbnail, pass, minPass, maxPass, minX, minY, periodX, periodY, bands);
+        }
+
+        public void thumbnailUpdate(ImageReader source, BufferedImage theThumbnail, int minX, int minY, int width, int height, int periodX, int periodY, int[] bands) {
+            processThumbnailUpdate(theThumbnail, minX, minY, width, height, periodX, periodY, bands);
+        }
+
+        public void thumbnailPassComplete(ImageReader source, BufferedImage theThumbnail) {
+            processThumbnailPassComplete(theThumbnail);
+        }
+
+        public void warningOccurred(ImageReader source, String warning) {
+            processWarningOccurred(warning);
+        }
+    }
 }

imageio/imageio-bmp/src/main/java/com/twelvemonkeys/imageio/plugins/bmp/BMPImageReaderSpi.java

@@ -65,10 +65,10 @@ public final class BMPImageReaderSpi extends ImageReaderSpi {
                 },
                 "com.twelvemonkeys.imageio.plugins.bmp.BMPImageReader",
                 new Class[]{ImageInputStream.class},
-                null,
+                new String[]{"com.sun.imageio.plugins.bmp.BMPImageWriterSpi"}, // We support the same native metadata format
-                true, null, null, null, null,
+                false, null, null, null, null,
                 true,
-                null, null,
+                BMPMetadata.nativeMetadataFormatName, "com.sun.imageio.plugins.bmp.BMPMetadataFormat",
                 null, null
         );
     }

imageio/imageio-bmp/src/main/java/com/twelvemonkeys/imageio/plugins/bmp/BMPMetadata.java

@@ -0,0 +1,342 @@
+/*
+ * Copyright (c) 2014, Harald Kuhr
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name "TwelveMonkeys" nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package com.twelvemonkeys.imageio.plugins.bmp;
+
+import com.twelvemonkeys.lang.Validate;
+import org.w3c.dom.Node;
+
+import javax.imageio.metadata.IIOMetadata;
+import javax.imageio.metadata.IIOMetadataFormatImpl;
+import javax.imageio.metadata.IIOMetadataNode;
+import java.awt.image.IndexColorModel;
+
+/**
+ * BMPMetadata.
+ */
+final class BMPMetadata extends IIOMetadata {
+    /** We return metadata in the exact same form as the JRE built-in, to be compatible with the BMPImageWriter. */
+    public static final String nativeMetadataFormatName = "javax_imageio_bmp_1.0";
+
+    private final DIBHeader header;
+    private final int[] colorMap;
+
+    BMPMetadata(final DIBHeader header, final int[] colorMap) {
+        this.header = Validate.notNull(header, "header");
+        this.colorMap = colorMap == null || colorMap.length == 0 ? null : colorMap;
+
+        standardFormatSupported = true;
+    }
+
+    @Override public boolean isReadOnly() {
+        return true;
+    }
+
+    @Override public Node getAsTree(final String formatName) {
+        if (formatName.equals(IIOMetadataFormatImpl.standardMetadataFormatName)) {
+            return getStandardTree();
+        }
+        else if (formatName.equals(nativeMetadataFormatName)) {
+            return getNativeTree();
+        }
+        else {
+            throw new IllegalArgumentException("Unsupported metadata format: " + formatName);
+        }
+    }
+
+    @Override public void mergeTree(final String formatName, final Node root) {
+        if (isReadOnly()) {
+            throw new IllegalStateException("Metadata is read-only");
+        }
+    }
+
+    @Override public void reset() {
+        if (isReadOnly()) {
+            throw new IllegalStateException("Metadata is read-only");
+        }
+    }
+
+    @Override
+    public String getNativeMetadataFormatName() {
+        return nativeMetadataFormatName;
+    }
+
+    private Node getNativeTree() {
+        IIOMetadataNode root = new IIOMetadataNode(nativeMetadataFormatName);
+
+        addChildNode(root, "BMPVersion", header.getBMPVersion());
+        addChildNode(root, "Width", header.getWidth());
+        addChildNode(root, "Height", header.getHeight());
+        addChildNode(root, "BitsPerPixel", (short) header.getBitCount());
+        addChildNode(root, "Compression", header.getCompression());
+        addChildNode(root, "ImageSize", header.getImageSize());
+
+        IIOMetadataNode pixelsPerMeter = addChildNode(root, "PixelsPerMeter", null);
+        addChildNode(pixelsPerMeter, "X", header.xPixelsPerMeter);
+        addChildNode(pixelsPerMeter, "Y", header.yPixelsPerMeter);
+
+        addChildNode(root, "ColorsUsed", header.colorsUsed);
+        addChildNode(root, "ColorsImportant", header.colorsImportant);
+
+        if (header.getSize() == DIB.BITMAP_V4_INFO_HEADER_SIZE || header.getSize() == DIB.BITMAP_V5_INFO_HEADER_SIZE) {
+            IIOMetadataNode mask = addChildNode(root, "Mask", null);
+            addChildNode(mask, "Red", header.masks[0]);
+            addChildNode(mask, "Green", header.masks[1]);
+            addChildNode(mask, "Blue", header.masks[2]);
+            addChildNode(mask, "Alpha", header.masks[3]);
+
+            addChildNode(root, "ColorSpaceType", header.colorSpaceType);
+
+            // It makes no sense to include these if colorSpaceType != 0, but native format does it...
+            IIOMetadataNode cieXYZEndPoints = addChildNode(root, "CIEXYZEndPoints", null);
+            addXYZPoints(cieXYZEndPoints, "Red", header.cieXYZEndpoints[0], header.cieXYZEndpoints[1], header.cieXYZEndpoints[2]);
+            addXYZPoints(cieXYZEndPoints, "Green", header.cieXYZEndpoints[3], header.cieXYZEndpoints[4], header.cieXYZEndpoints[5]);
+            addXYZPoints(cieXYZEndPoints, "Blue", header.cieXYZEndpoints[6], header.cieXYZEndpoints[7], header.cieXYZEndpoints[8]);
+
+            // TODO: Gamma?! Will need a new native format version...
+
+            addChildNode(root, "Intent", header.intent);
+
+            // TODO: Profile data & profile size
+        }
+
+        // Palette
+        if (colorMap != null) {
+            IIOMetadataNode paletteNode = addChildNode(root, "Palette", null);
+
+            // The original BitmapCoreHeader has only RGB values in the palette, all others have RGBA
+            boolean hasAlpha = header.getSize() != DIB.BITMAP_CORE_HEADER_SIZE;
+
+            for (int color : colorMap) {
+                // NOTE: The native format has the red and blue values mixed up, we'll report the correct values
+                IIOMetadataNode paletteEntry = addChildNode(paletteNode, "PaletteEntry", null);
+                addChildNode(paletteEntry, "Red", (byte) ((color >> 16) & 0xff));
+                addChildNode(paletteEntry, "Green", (byte) ((color >> 8) & 0xff));
+                addChildNode(paletteEntry, "Blue", (byte) (color & 0xff));
+
+                // Not sure why the native format specifies this, as no palette-based BMP has alpha
+                if (hasAlpha) {
+                    addChildNode(paletteEntry, "Alpha", (byte) ((color >>> 24) & 0xff));
+                }
+            }
+        }
+
+        return root;
+    }
+
+    private void addXYZPoints(IIOMetadataNode cieXYZNode, String color, double colorX, double colorY, double colorZ) {
+        IIOMetadataNode colorNode = addChildNode(cieXYZNode, color, null);
+        addChildNode(colorNode, "X", colorX);
+        addChildNode(colorNode, "Y", colorY);
+        addChildNode(colorNode, "Z", colorZ);
+    }
+
+    private IIOMetadataNode addChildNode(final IIOMetadataNode parent,
+                                         final String name,
+                                         final Object object) {
+        IIOMetadataNode child = new IIOMetadataNode(name);
+
+        if (object != null) {
+            child.setUserObject(object); // TODO: Should we always store user object?!?!
+            child.setNodeValue(object.toString()); // TODO: Fix this line
+        }
+
+        parent.appendChild(child);
+
+        return child;
+    }
+
+    @Override protected IIOMetadataNode getStandardChromaNode() {
+        // NOTE: BMP files may contain a color map, even if true color...
+        // Not sure if this is a good idea to expose to the meta data,
+        // as it might be unexpected... Then again...
+        if (colorMap != null) {
+            IIOMetadataNode chroma = new IIOMetadataNode("Chroma");
+
+            IIOMetadataNode palette = new IIOMetadataNode("Palette");
+            chroma.appendChild(palette);
+
+            for (int i = 0; i < colorMap.length; i++) {
+                IIOMetadataNode paletteEntry = new IIOMetadataNode("PaletteEntry");
+                paletteEntry.setAttribute("index", Integer.toString(i));
+
+                paletteEntry.setAttribute("red", Integer.toString((colorMap[i] >> 16) & 0xff));
+                paletteEntry.setAttribute("green", Integer.toString((colorMap[i] >> 8) & 0xff));
+                paletteEntry.setAttribute("blue", Integer.toString(colorMap[i] & 0xff));
+
+                palette.appendChild(paletteEntry);
+            }
+
+            return chroma;
+        }
+
+        return null;
+    }
+
+    @Override protected IIOMetadataNode getStandardCompressionNode() {
+        IIOMetadataNode compression = new IIOMetadataNode("Compression");
+        IIOMetadataNode compressionTypeName = addChildNode(compression, "CompressionTypeName", null);
+        compressionTypeName.setAttribute("value", "NONE");
+
+        return compression;
+//        switch (header.getImageType()) {
+//            case TGA.IMAGETYPE_COLORMAPPED_RLE:
+//            case TGA.IMAGETYPE_TRUECOLOR_RLE:
+//            case TGA.IMAGETYPE_MONOCHROME_RLE:
+//            case TGA.IMAGETYPE_COLORMAPPED_HUFFMAN:
+//            case TGA.IMAGETYPE_COLORMAPPED_HUFFMAN_QUADTREE:
+//                IIOMetadataNode node = new IIOMetadataNode("Compression");
+//                IIOMetadataNode compressionTypeName = new IIOMetadataNode("CompressionTypeName");
+//
+//                // Compression can be RLE4, RLE8, PNG, JPEG or NONE
+//                String value = header.getImageType() == TGA.IMAGETYPE_COLORMAPPED_HUFFMAN || header.getImageType() == TGA.IMAGETYPE_COLORMAPPED_HUFFMAN_QUADTREE
+//                                ? "Uknown" : "RLE";
+//                compressionTypeName.setAttribute("value", value);
+//                node.appendChild(compressionTypeName);
+//
+//                IIOMetadataNode lossless = new IIOMetadataNode("Lossless");
+//                lossless.setAttribute("value", "TRUE"); // TODO: Unless JPEG!
+//                node.appendChild(lossless);
+//
+//                return node;
+//            default:
+//                // No compression
+//                return null;
+//        }
+    }
+
+    @Override protected IIOMetadataNode getStandardDataNode() {
+        IIOMetadataNode node = new IIOMetadataNode("Data");
+
+//        IIOMetadataNode planarConfiguration = new IIOMetadataNode("PlanarConfiguration");
+//        planarConfiguration.setAttribute("value", "PixelInterleaved");
+//        node.appendChild(planarConfiguration);
+
+//        IIOMetadataNode sampleFormat = new IIOMetadataNode("SampleFormat");
+//        switch (header.getImageType()) {
+//            case TGA.IMAGETYPE_COLORMAPPED:
+//            case TGA.IMAGETYPE_COLORMAPPED_RLE:
+//            case TGA.IMAGETYPE_COLORMAPPED_HUFFMAN:
+//            case TGA.IMAGETYPE_COLORMAPPED_HUFFMAN_QUADTREE:
+//                sampleFormat.setAttribute("value", "Index");
+//                break;
+//            default:
+//                sampleFormat.setAttribute("value", "UnsignedIntegral");
+//                break;
+//        }
+
+//        node.appendChild(sampleFormat);
+
+        IIOMetadataNode bitsPerSample = new IIOMetadataNode("BitsPerSample");
+        switch (header.getBitCount()) {
+            case 1:
+            case 2:
+            case 4:
+            case 8:
+                bitsPerSample.setAttribute("value", createListValue(1, Integer.toString(header.getBitCount())));
+                break;
+            case 16:
+                // TODO: Consult masks here!
+                bitsPerSample.setAttribute("value", createListValue(4, Integer.toString(4)));
+                break;
+            case 24:
+                bitsPerSample.setAttribute("value", createListValue(3, Integer.toString(8)));
+                break;
+            case 32:
+                bitsPerSample.setAttribute("value", createListValue(4, Integer.toString(8)));
+                break;
+        }
+
+        node.appendChild(bitsPerSample);
+
+        // TODO: Do we need MSB?
+//        IIOMetadataNode sampleMSB = new IIOMetadataNode("SampleMSB");
+//        sampleMSB.setAttribute("value", createListValue(header.getChannels(), "0"));
+
+        return node;
+    }
+
+    private String createListValue(final int itemCount, final String... values) {
+        StringBuilder buffer = new StringBuilder();
+
+        for (int i = 0; i < itemCount; i++) {
+            if (buffer.length() > 0) {
+                buffer.append(' ');
+            }
+
+            buffer.append(values[i % values.length]);
+        }
+
+        return buffer.toString();
+    }
+
+    @Override protected IIOMetadataNode getStandardDimensionNode() {
+        if (header.xPixelsPerMeter > 0 || header.yPixelsPerMeter > 0) {
+            IIOMetadataNode dimension = new IIOMetadataNode("Dimension");
+
+            addChildNode(dimension, "PixelAspectRatio", null);
+            addChildNode(dimension, "HorizontalPhysicalPixelSpacing", null);
+            addChildNode(dimension, "VerticalPhysicalPixelSpacing", null);
+
+            //        IIOMetadataNode imageOrientation = new IIOMetadataNode("ImageOrientation");
+            //
+            //        if (header.topDown) {
+            //            imageOrientation.setAttribute("value", "FlipH");
+            //        }
+            //        else {
+            //            imageOrientation.setAttribute("value", "Normal");
+            //        }
+            //
+            //        dimension.appendChild(imageOrientation);
+
+            return dimension;
+        }
+
+        return null;
+    }
+
+    // No document node
+
+    // No text node
+
+    // No tiling
+
+    @Override protected IIOMetadataNode getStandardTransparencyNode() {
+        return null;
+
+//        IIOMetadataNode transparency = new IIOMetadataNode("Transparency");
+//
+//        IIOMetadataNode alpha = new IIOMetadataNode("Alpha");
+//
+//        // TODO: Consult masks
+//        alpha.setAttribute("value", header.getBitCount() == 32 ? "nonpremultiplied" : "none");
+//        transparency.appendChild(alpha);
+//
+//        return transparency;
+    }
+}

imageio/imageio-bmp/src/main/java/com/twelvemonkeys/imageio/plugins/bmp/DIB.java

@@ -39,8 +39,6 @@ package com.twelvemonkeys.imageio.plugins.bmp;
  * @see <a href="http://en.wikipedia.org/wiki/ICO_(icon_image_file_format)">ICO file format (Wikipedia)</a>
  */
 interface DIB {
-    int TYPE_UNKNOWN = 0;
-
     int TYPE_ICO = 1;
     int TYPE_CUR = 2;
 
@@ -89,6 +87,13 @@ interface DIB {
     // int COMPRESSION_CMYK_RLE8 = 12;
     // int COMPRESSION_CMYK_RLE5 = 13;
 
+    /* Color space types. */
+    int LCS_CALIBRATED_RGB = 0;
+    int LCS_sRGB = 's' << 24 | 'R' << 16 | 'G' << 8 | 'B'; // 0x73524742
+    int LCS_WINDOWS_COLOR_SPACE = 'W' << 24 | 'i' << 16 | 'n' << 8 | ' '; // 0x57696e20
+    int PROFILE_LINKED = 'L' << 24 | 'I' << 16 | 'N' << 8 | 'K'; // 0x4c494e4b
+    int PROFILE_EMBEDDED = 'M' << 24 | 'B' << 16 | 'E' << 8 | 'D'; // 0x4d424544
+
     /** PNG "magic" identifier */
     long PNG_MAGIC = 0x89l << 56 | (long) 'P' << 48 | (long) 'N' << 40 | (long) 'G' << 32 | 0x0dl << 24 | 0x0al << 16 | 0x1al << 8 | 0x0al;
 }

imageio/imageio-bmp/src/main/java/com/twelvemonkeys/imageio/plugins/bmp/DIBHeader.java

@@ -41,6 +41,9 @@ import java.io.IOException;
  * @see <a href="http://en.wikipedia.org/wiki/BMP_file_format">BMP file format (Wikipedia)</a>
  */
 abstract class DIBHeader {
+    // Roughly 72 DPI
+    private final int DEFAULT_PIXELS_PER_METER = 2835;
+
     protected int size;
     protected int width;
     // NOTE: If a bitmask is present, this value includes the height of the mask
@@ -70,7 +73,16 @@ abstract class DIBHeader {
     // 0 means all colors are important
     protected int colorsImportant;
 
+    // V4+ members below
     protected int[] masks;
+    protected int colorSpaceType;
+    protected double[] cieXYZEndpoints;
+    protected int[] gamma;
+
+    // V5+ members below
+    protected int intent;
+    protected long profileData;
+    protected long profileSize;
 
     protected DIBHeader() {
     }
@@ -139,19 +151,19 @@ abstract class DIBHeader {
     }
 
     public int getXPixelsPerMeter() {
-        return xPixelsPerMeter;
+        return xPixelsPerMeter != 0 ? xPixelsPerMeter : DEFAULT_PIXELS_PER_METER;
     }
 
     public int getYPixelsPerMeter() {
-        return yPixelsPerMeter;
+        return yPixelsPerMeter != 0 ? yPixelsPerMeter : DEFAULT_PIXELS_PER_METER;
     }
 
     public int getColorsUsed() {
-        return colorsUsed;
+        return colorsUsed != 0 ? colorsUsed : 1 << bitCount;
     }
 
     public int getColorsImportant() {
-        return colorsImportant;
+        return colorsImportant != 0 ? colorsImportant : getColorsUsed();
     }
 
     public boolean hasMasks() {
@@ -167,10 +179,11 @@ abstract class DIBHeader {
                         "colors used: %d%s, colors important: %d%s",
                 getClass().getSimpleName(),
                 getSize(), getWidth(), getHeight(), getPlanes(), getBitCount(), getCompression(),
-                getImageSize(), (getImageSize() == 0 ? " (unknown)" : ""),
+                getImageSize(), (imageSize == 0 ? " (calculated)" : ""),
-                getXPixelsPerMeter(), getYPixelsPerMeter(),
+                getXPixelsPerMeter(),
-                getColorsUsed(), (getColorsUsed() == 0 ? " (unknown)" : ""),
+                getYPixelsPerMeter(),
-                getColorsImportant(), (getColorsImportant() == 0 ? " (all)" : "")
+                getColorsUsed(), (colorsUsed == 0 ? " (unknown)" : ""),
+                getColorsImportant(), (colorsImportant == 0 ? " (all)" : "")
         );
     }
 
@@ -183,6 +196,8 @@ abstract class DIBHeader {
         return masks;
     }
 
+    protected abstract String getBMPVersion();
+
     // TODO: Get rid of code duplication below...
 
     static final class BitmapCoreHeader extends DIBHeader {
@@ -204,10 +219,10 @@ abstract class DIBHeader {
 
             planes = pStream.readUnsignedShort();
             bitCount = pStream.readUnsignedShort();
+        }
 
-            // Roughly 72 DPI
+        public String getBMPVersion() {
-            xPixelsPerMeter = 2835;
+            return "BMP v. 2.x";
-            yPixelsPerMeter = 2835;
         }
     }
 
@@ -239,12 +254,7 @@ abstract class DIBHeader {
             planes = pStream.readUnsignedShort();
             bitCount = pStream.readUnsignedShort();
 
-            if (pSize == DIB.OS2_V2_HEADER_16_SIZE) {
+            if (pSize != DIB.OS2_V2_HEADER_16_SIZE) {
-                // Roughly 72 DPI
-                xPixelsPerMeter = 2835;
-                yPixelsPerMeter = 2835;
-            }
-            else {
                 compression = pStream.readInt();
 
                 imageSize = pStream.readInt();
@@ -256,6 +266,7 @@ abstract class DIBHeader {
                 colorsImportant = pStream.readInt();
             }
 
+            // TODO: Use? These fields are not reflected in metadata as per now...
             int units = pStream.readShort();
             int reserved = pStream.readShort();
             int recording = pStream.readShort(); // Recording algorithm
@@ -265,6 +276,10 @@ abstract class DIBHeader {
             int colorEncoding = pStream.readInt(); // Color model used in bitmap
             int identifier = pStream.readInt(); // Reserved for application use
         }
+
+        public String getBMPVersion() {
+            return "BMP v. 2.2";
+        }
     }
 
 
@@ -306,6 +321,11 @@ abstract class DIBHeader {
             colorsUsed = pStream.readInt();
             colorsImportant = pStream.readInt();
         }
+
+        public String getBMPVersion() {
+            // This is to be compatible with the native metadata of the original com.sun....BMPMetadata
+            return compression == DIB.COMPRESSION_BITFIELDS ? "BMP v. 3.x NT" : "BMP v. 3.x";
+        }
     }
 
     /**
@@ -342,6 +362,10 @@ abstract class DIBHeader {
 
             masks = readMasks(pStream);
         }
+
+        public String getBMPVersion() {
+            return "BMP v. 3.x Photoshop";
+        }
     }
 
     /**
@@ -377,10 +401,22 @@ abstract class DIBHeader {
 
             masks = readMasks(pStream);
 
-            byte[] data = new byte[52];
+            colorSpaceType = pStream.readInt(); // Should be 0 for V4
-            pStream.readFully(data);
+            cieXYZEndpoints = new double[9];
 
-//            System.out.println("data = " + Arrays.toString(data));
+            for (int i = 0; i < cieXYZEndpoints.length; i++) {
+                cieXYZEndpoints[i] = pStream.readInt(); // TODO: Hmmm...?
+            }
+
+            gamma = new int[3];
+
+            for (int i = 0; i < gamma.length; i++) {
+                gamma[i] = pStream.readInt();
+            }
+        }
+
+        public String getBMPVersion() {
+            return "BMP v. 4.x";
         }
     }
 
@@ -417,10 +453,28 @@ abstract class DIBHeader {
 
             masks = readMasks(pStream);
 
-            byte[] data = new byte[68];
+            colorSpaceType = pStream.readInt();
-            pStream.readFully(data);
 
-//            System.out.println("data = " + Arrays.toString(data));
+            cieXYZEndpoints = new double[9];
+
+            for (int i = 0; i < cieXYZEndpoints.length; i++) {
+                cieXYZEndpoints[i] = pStream.readInt(); // TODO: Hmmm...?
+            }
+
+            gamma = new int[3];
+
+            for (int i = 0; i < gamma.length; i++) {
+                gamma[i] = pStream.readInt();
+            }
+
+            intent = pStream.readInt(); // TODO: Verify if this is same as ICC intent
+            profileData = pStream.readInt() & 0xffffffffL;
+            profileSize = pStream.readInt() & 0xffffffffL;
+            pStream.readInt(); // Reserved
+        }
+
+        public String getBMPVersion() {
+            return "BMP v. 5.x";
         }
     }
 }

imageio/imageio-bmp/src/test/java/com/twelvemonkeys/imageio/plugins/bmp/BMPImageReaderTest.java

@@ -2,19 +2,30 @@ package com.twelvemonkeys.imageio.plugins.bmp;
 
 import com.twelvemonkeys.imageio.util.ImageReaderAbstractTestCase;
 import org.junit.Test;
+import org.mockito.InOrder;
+import org.w3c.dom.Node;
+import org.w3c.dom.NodeList;
 
 import javax.imageio.ImageReader;
 import javax.imageio.ImageTypeSpecifier;
+import javax.imageio.event.IIOReadProgressListener;
+import javax.imageio.metadata.IIOMetadata;
+import javax.imageio.metadata.IIOMetadataNode;
 import javax.imageio.spi.ImageReaderSpi;
 import java.awt.*;
 import java.io.IOException;
-import java.net.URL;
+import java.lang.reflect.Constructor;
+import java.net.URISyntaxException;
 import java.util.Arrays;
 import java.util.Iterator;
 import java.util.List;
 
-import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.*;
-import static org.junit.Assert.assertTrue;
+import static org.mockito.Matchers.anyInt;
+import static org.mockito.Matchers.eq;
+import static org.mockito.Mockito.atLeastOnce;
+import static org.mockito.Mockito.inOrder;
+import static org.mockito.Mockito.mock;
 
 /**
  * BMPImageReaderTest
@@ -160,4 +171,189 @@ public class BMPImageReaderTest extends ImageReaderAbstractTestCase<BMPImageRead
         }
     }
 
+    @Test
+    public void testAddIIOReadProgressListenerCallbacksJPEG() {
+        ImageReader reader = createReader();
+        TestData data = new TestData(getClassLoaderResource("/bmpsuite/q/rgb24jpeg.bmp"), new Dimension(127, 64));
+        reader.setInput(data.getInputStream());
+
+        IIOReadProgressListener listener = mock(IIOReadProgressListener.class);
+        reader.addIIOReadProgressListener(listener);
+
+        try {
+            reader.read(0);
+        }
+        catch (IOException e) {
+            fail("Could not read image");
+        }
+
+        // At least imageStarted and imageComplete, plus any number of imageProgress
+        InOrder ordered = inOrder(listener);
+        ordered.verify(listener).imageStarted(reader, 0);
+        ordered.verify(listener, atLeastOnce()).imageProgress(eq(reader), anyInt());
+        ordered.verify(listener).imageComplete(reader);
+    }
+
+    @Test
+    public void testAddIIOReadProgressListenerCallbacksPNG() {
+        ImageReader reader = createReader();
+        TestData data = new TestData(getClassLoaderResource("/bmpsuite/q/rgb24png.bmp"), new Dimension(127, 64));
+        reader.setInput(data.getInputStream());
+
+        IIOReadProgressListener listener = mock(IIOReadProgressListener.class);
+        reader.addIIOReadProgressListener(listener);
+
+        try {
+            reader.read(0);
+        }
+        catch (IOException e) {
+            fail("Could not read image");
+        }
+
+        // At least imageStarted and imageComplete, plus any number of imageProgress
+        InOrder ordered = inOrder(listener);
+        ordered.verify(listener).imageStarted(reader, 0);
+        ordered.verify(listener, atLeastOnce()).imageProgress(eq(reader), anyInt());
+        ordered.verify(listener).imageComplete(reader);
+    }
+
+    @Test
+    public void testMetadataEqualsJRE() throws IOException, URISyntaxException {
+        // Ignore this test if not on an Oracle JRE (com.sun...BMPImageReader not available)
+        ImageReader jreReader;
+        try {
+            @SuppressWarnings("unchecked")
+            Class<ImageReader> jreReaderClass = (Class<ImageReader>) Class.forName("com.sun.imageio.plugins.bmp.BMPImageReader");
+            Constructor<ImageReader> constructor = jreReaderClass.getConstructor(ImageReaderSpi.class);
+            jreReader = constructor.newInstance(new Object[] {null});
+        }
+        catch (Exception e) {
+            System.err.println("WARNING: Skipping metadata tests: " + e);
+            e.printStackTrace();
+            return;
+        }
+
+        ImageReader reader = createReader();
+
+        for (TestData data : getTestData()) {
+            if (data.getInput().toString().contains("pal8offs")) {
+                continue;
+            }
+
+            reader.setInput(data.getInputStream());
+            jreReader.setInput(data.getInputStream());
+
+            IIOMetadata metadata = reader.getImageMetadata(0);
+
+            // WORKAROUND: JRE reader does not reset metadata on setInput. Invoking getWidth forces re-read of header and metadata.
+            try {
+                jreReader.getWidth(0);
+            }
+            catch (Exception e) {
+                System.err.println("WARNING: Reading " + data + " caused exception: " + e.getMessage());
+                continue;
+            }
+            IIOMetadata jreMetadata = jreReader.getImageMetadata(0);
+
+            assertEquals(true, metadata.isStandardMetadataFormatSupported());
+            assertEquals(jreMetadata.getNativeMetadataFormatName(), metadata.getNativeMetadataFormatName());
+            assertArrayEquals(jreMetadata.getExtraMetadataFormatNames(), metadata.getExtraMetadataFormatNames());
+
+            // TODO: Allow our standard metadata to be richer, but contain at least the information from the JRE impl
+
+            for (String format : jreMetadata.getMetadataFormatNames()) {
+                String absolutePath = data.toString();
+                String localPath = absolutePath.substring(absolutePath.lastIndexOf("test-classes") + 12);
+
+                Node expectedTree = jreMetadata.getAsTree(format);
+                Node actualTree = metadata.getAsTree(format);
+
+//                try {
+                    assertNodeEquals(localPath + " - " + format, expectedTree, actualTree);
+//                }
+//                catch (AssertionError e) {
+//                    ByteArrayOutputStream expected = new ByteArrayOutputStream();
+//                    ByteArrayOutputStream actual = new ByteArrayOutputStream();
+//
+//                    new XMLSerializer(expected, "UTF-8").serialize(expectedTree, false);
+//                    new XMLSerializer(actual, "UTF-8").serialize(actualTree, false);
+//
+//                    assertEquals(e.getMessage(), new String(expected.toByteArray(), "UTF-8"), new String(actual.toByteArray(), "UTF-8"));
+//
+//                    throw e;
+//                }
+            }
+        }
+    }
+
+    private void assertNodeEquals(final String message, final Node expected, final Node actual) {
+        assertEquals(message + " class differs", expected.getClass(), actual.getClass());
+
+        if (!excludeEqualValueTest(expected)) {
+            assertEquals(message, expected.getNodeValue(), actual.getNodeValue());
+
+            if (expected instanceof IIOMetadataNode) {
+                IIOMetadataNode expectedIIO = (IIOMetadataNode) expected;
+                IIOMetadataNode actualIIO = (IIOMetadataNode) actual;
+
+                assertEquals(message, expectedIIO.getUserObject(), actualIIO.getUserObject());
+            }
+        }
+
+        NodeList expectedChildNodes = expected.getChildNodes();
+        NodeList actualChildNodes = actual.getChildNodes();
+
+        assertEquals(message + " child length differs: " + toString(expectedChildNodes) + " != " + toString(actualChildNodes),
+                expectedChildNodes.getLength(), actualChildNodes.getLength());
+
+        for (int i = 0; i < expectedChildNodes.getLength(); i++) {
+            Node expectedChild = expectedChildNodes.item(i);
+            Node actualChild = actualChildNodes.item(i);
+
+            assertEquals(message + " node name differs", expectedChild.getLocalName(), actualChild.getLocalName());
+            assertNodeEquals(message + "/" + expectedChild.getLocalName(), expectedChild, actualChild);
+        }
+    }
+
+    private boolean excludeEqualValueTest(final Node expected) {
+        if (expected.getLocalName().equals("ImageSize")) {
+            // JRE metadata returns 0, even if known in reader...
+            return true;
+        }
+        if (expected.getLocalName().equals("ColorsImportant")) {
+            // JRE metadata returns 0, even if known in reader...
+            return true;
+        }
+        if (expected.getParentNode() != null && expected.getParentNode().getLocalName().equals("PaletteEntry") && !expected.getNodeValue().equals("Green")) {
+            // JRE metadata returns RGB colors in BGR order
+            // JRE metadata returns 0 for alpha, when -1 (0xff) is at least just as correct (why contain alpha at all?)
+            return true;
+        }
+        if (expected.getLocalName().equals("Height") && expected.getNodeValue().startsWith("-")) {
+            // JRE metadata returns negative height for bottom/up images
+            // TODO: Decide if we should do the same, as there is no "orientation" or flag for bottom/up
+            return true;
+        }
+
+        return false;
+    }
+
+    private String toString(final NodeList list) {
+        if (list.getLength() == 0) {
+            return "[]";
+        }
+
+        StringBuilder builder = new StringBuilder("[");
+        for (int i = 0; i < list.getLength(); i++) {
+            if (i > 0) {
+                builder.append(", ");
+            }
+
+            Node node = list.item(i);
+            builder.append(node.getLocalName());
+        }
+        builder.append("]");
+
+        return builder.toString();
+    }
 }