ImageIO write support

README.md

@@ -9,10 +9,15 @@ Download and run "ant". The jar "target/jj2000.jar" contains the API code, the "
 
 ImageIO support
 ---------------
-The Jar supplies an ImageIO reader implementation, so reading is as simple as `javax.imageio.ImageIO.read(new File("input.jp2"))`
-(thanks to @keinhaar for the PR). The reader doesn't support metadata.
+The Jar supplies an ImageIO support, so reading is as simple as 
 
-There is currently no ImageIO writer support.
+`javax.imageio.ImageIO.read(new File("input.jp2"))`
+
+and for writing 
+
+`ImageIO.write(image, "JPEG2000", new File("image.jp2"));`
+
+(thanks to @keinhaar for the PR). Both, reader and writer, do not support metadata.
 
 How to read a JP2 or JPX image
 ------------------------------

src/main/java/com/github/jpeg2000/imageio/ImageReaderImpl.java

@@ -60,7 +60,7 @@ public String[] getFileSuffixes()
     @Override
     public String getDescription(Locale locale)
     {
-        return "JPEG2000 ImageIO Support";
+        return "JPEG2000 ImageIO Reader Support";
     }
 
 }

src/main/java/com/github/jpeg2000/imageio/ImageWriterImpl.java

@@ -0,0 +1,52 @@
+package com.github.jpeg2000.imageio;
+
+import java.io.IOException;
+import java.util.Locale;
+
+import javax.imageio.ImageTypeSpecifier;
+import javax.imageio.ImageWriter;
+import javax.imageio.spi.ImageWriterSpi;
+import javax.imageio.stream.ImageOutputStream;
+
+/**
+ * JPEG2000 ImageIO Writer SPI. 
+ */
+public class ImageWriterImpl extends ImageWriterSpi
+{
+    @Override
+    public Class[] getOutputTypes()
+    {
+        return new Class[] {ImageOutputStream.class};
+    }
+
+    @Override
+    public ImageWriter createWriterInstance(Object extension) throws IOException
+    {
+        return new JPEG2000Writer(this);
+    }
+
+    @Override
+    public String[] getFormatNames()
+    {
+        return new String[] {"jpeg2000", "JPEG2000"};
+    }
+
+    @Override
+    public String[] getFileSuffixes()
+    {
+        return new String[] {"jp2", "j2k"};
+    }
+
+    @Override
+    public String getDescription(Locale locale)
+    {
+        return "JPEG2000 ImageIO Writer Support";
+    }
+
+    @Override
+    public boolean canEncodeImage(ImageTypeSpecifier type)
+    {
+        return true;
+    }
+
+}

src/main/java/com/github/jpeg2000/imageio/JPEG2000Writer.java

@@ -0,0 +1,128 @@
+package com.github.jpeg2000.imageio;
+
+import java.awt.image.BufferedImage;
+import java.awt.image.ColorModel;
+import java.awt.image.RenderedImage;
+import java.awt.image.WritableRaster;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.util.Hashtable;
+
+import javax.imageio.IIOImage;
+import javax.imageio.ImageTypeSpecifier;
+import javax.imageio.ImageWriteParam;
+import javax.imageio.ImageWriter;
+import javax.imageio.metadata.IIOMetadata;
+import javax.imageio.stream.ImageOutputStream;
+
+import com.github.jpeg2000.J2KWriter;
+
+public class JPEG2000Writer extends ImageWriter
+{
+    public JPEG2000Writer(ImageWriterImpl imageWriterImpl)
+    {
+        super(imageWriterImpl);
+    }
+
+    @Override
+    public IIOMetadata getDefaultStreamMetadata(ImageWriteParam param)
+    {
+        return null;
+    }
+
+    @Override
+    public IIOMetadata getDefaultImageMetadata(ImageTypeSpecifier imageType, ImageWriteParam param)
+    {
+        return null;
+    }
+
+    @Override
+    public IIOMetadata convertStreamMetadata(IIOMetadata inData, ImageWriteParam param)
+    {
+        return null;
+    }
+
+    @Override
+    public IIOMetadata convertImageMetadata(IIOMetadata inData, ImageTypeSpecifier imageType, ImageWriteParam param)
+    {
+        return null;
+    }
+
+    @Override
+    public void write(IIOMetadata streamMetadata, IIOImage iioimage, ImageWriteParam param) throws IOException
+    {
+        //We can savely cast here, because the setOutput does not accept anything else.
+        ImageOutputStream stream = (ImageOutputStream) getOutput();
+        RenderedImage image = iioimage.getRenderedImage();
+        BufferedImage bimage = null;
+        if(image instanceof BufferedImage)
+        {
+            bimage = (BufferedImage) image;
+        }
+        else
+        {
+            bimage = convertToBufferedImage(image);
+        }
+        J2KWriter writer = new J2KWriter();
+        writer.setCompressionRatio(15, false);
+        writer.setSource(bimage, 128);
+        writer.write(new Output(stream));       
+    }
+
+    /**
+     * Translate between OutputStream and ImageOutputStream
+     */
+    class Output extends OutputStream
+    {
+        private ImageOutputStream stream;
+
+        public Output(ImageOutputStream stream)
+        {
+            this.stream = stream;
+        }
+
+        @Override
+        public void write(int b) throws IOException
+        {
+            stream.write(b);
+        }
+
+        @Override
+        public void write(byte[] b, int off, int len) throws IOException
+        {
+            stream.write(b, off, len);
+        }
+
+        @Override
+        public void close() throws IOException
+        {
+            stream.close();
+        }
+    }
+
+    /**
+     * Convert any other RenderedImage to BufferedImage
+     * @param img
+     * @return
+     */
+    private BufferedImage convertToBufferedImage(RenderedImage img)
+    {
+        ColorModel cm = img.getColorModel();
+        int width = img.getWidth();
+        int height = img.getHeight();
+        WritableRaster raster = cm.createCompatibleWritableRaster(width, height);
+        boolean isAlphaPremultiplied = cm.isAlphaPremultiplied();
+        Hashtable properties = new Hashtable();
+        String[] keys = img.getPropertyNames();
+        if(keys != null)
+        {
+            for(String key : keys)
+            {
+                properties.put(key, img.getProperty(key));
+            }
+        }
+        BufferedImage bimage = new BufferedImage(cm, raster, isAlphaPremultiplied, properties);
+        img.copyData(raster);
+        return bimage;
+    }
+}

src/main/resources/META-INF/services/javax.imageio.spi.ImageWriterSpi

@@ -0,0 +1 @@
+com.github.jpeg2000.imageio.ImageWriterImpl