AFP Output Changes:

- Fixed positioning of Java2D-based images (when GOCA is enabled). GraphicsDataDescriptor had a bit order bug. The Graphics2D image handler didn't save state and reposition the image origin.
- Switched bitmap image handling in AFPGraphics2D to (re-)use AFPImageHandlerRenderedImage so it can profit from it's advanced image conversion functionality. This also avoids some bugs with certain image formats.
- Added enhanced dithering functionality for images that need to be converted to bi-level images.


git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/trunk@953952 13f79535-47bb-0310-9956-ffa450edef68

src/documentation/content/xdocs/trunk/output.xml

         latest features. We're trying to make AFP output work in as many environments as possible.
         However, to make AFP output work on older environments it is recommended to set to
         configuration to 1 bit per pixel (see below on how to do this). In this case, all images
-        are converted to bi-level images using IOCA function set 10 (FS10). If a higher number of
-        bits per pixel is configured, FOP has to switch to at least FS11 which may not work
-        everywhere.
+        are converted to bi-level images using IOCA function set 10 (FS10) and are enclosed in
+        page-segments since some implementation cannot deal with IOCA objects directly.
+        If a higher number of bits per pixel is configured, FOP has to switch to at least FS11
+        which may not work everywhere.
       </p>
     </section>
     <section id="afp-configuration">
         colors. This will only have an effect if the color mode is set to "color". Example:
       </p>
       <source><![CDATA[
-      <images mode="color" cmyk="true"/>
-]]></source>
+      <images mode="color" cmyk="true"/>]]></source>
+        <p>
+          When the color mode is set to 1 bit (bi-level), the "dithering-quality" attribute can
+          be used to select the level of quality to use when converting images to bi-level images.
+          Valid values for this attribute are floating point numbers from 0.0 (fastest) to
+          1.0 (best), or special values: "minimum" (=0.0), "maximum" (1.0),
+          "medium" (0.5, the default). For the higher settings to work as expected, JAI needs to
+          be present in the classpath. If JAI is present, 0.0 results in a minimal darkness-level
+          switching between white and black. 0.5 does bayer-based dithering and 1.0 will use
+          error-diffusion dithering. The higher the value, the higher the quality and the slower
+          the processing of the images.
+        </p>
+        <source><![CDATA[
+      <images mode="b+w" bits-per-pixel="1" dithering-quality="maximum"/>]]></source>
       </section>
       <section id="afp-shading-config">
         <title>Shading</title>

src/java/org/apache/fop/afp/AFPGraphics2D.java

 import java.awt.image.renderable.RenderableImage;
 import java.io.IOException;
 
-import org.apache.commons.io.output.ByteArrayOutputStream;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
 import org.apache.xmlgraphics.java2d.GraphicContext;
 import org.apache.xmlgraphics.java2d.StrokingTextHandler;
 import org.apache.xmlgraphics.java2d.TextHandler;
-import org.apache.xmlgraphics.ps.ImageEncodingHelper;
-import org.apache.xmlgraphics.util.MimeConstants;
 import org.apache.xmlgraphics.util.UnitConv;
 
 import org.apache.fop.afp.goca.GraphicsSetLineType;
 import org.apache.fop.afp.svg.AFPGraphicsConfiguration;
 import org.apache.fop.afp.util.CubicBezierApproximator;
 import org.apache.fop.fonts.FontInfo;
+import org.apache.fop.render.afp.AFPImageHandlerRenderedImage;
+import org.apache.fop.render.afp.AFPRenderingContext;
 import org.apache.fop.svg.NativeImageHandler;
 
 /**
                                  BufferedImage.TYPE_INT_ARGB);
     }
 
-    private AFPImageObjectInfo createImageObjectInfo(
-            RenderedImage img, int x, int y, int width, int height) throws IOException {
-        ImageInfo imageInfo = new ImageInfo(null, "image/unknown");
-        ImageSize size = new ImageSize(img.getWidth(), img.getHeight(), 72);
-        imageInfo.setSize(size);
-
-        ImageRendered imageRendered = new ImageRendered(imageInfo, img, null);
-        RenderedImage renderedImage = imageRendered.getRenderedImage();
-
-        // create image object info
-        AFPImageObjectInfo imageObjectInfo = new AFPImageObjectInfo();
-
-        imageObjectInfo.setMimeType(MimeConstants.MIME_AFP_IOCA_FS45);
-
-        int bitsPerPixel = paintingState.getBitsPerPixel();
-        imageObjectInfo.setBitsPerPixel(bitsPerPixel);
-
-        imageObjectInfo.setResourceInfo(resourceInfo);
-
-        int dataHeight = renderedImage.getHeight();
-        imageObjectInfo.setDataHeight(dataHeight);
-
-        int dataWidth = renderedImage.getWidth();
-        imageObjectInfo.setDataWidth(dataWidth);
-
-        int resolution = paintingState.getResolution();
-        imageObjectInfo.setDataWidthRes(resolution);
-        imageObjectInfo.setDataHeightRes(resolution);
-
-        boolean colorImages = paintingState.isColorImages();
-        imageObjectInfo.setColor(colorImages);
-
-        ByteArrayOutputStream boas = new ByteArrayOutputStream();
-        ImageEncodingHelper.encodeRenderedImageAsRGB(renderedImage, boas);
-        byte[] imageData = boas.toByteArray();
-
-        // convert to grayscale
-        if (!colorImages) {
-            boas.reset();
-            imageObjectInfo.setBitsPerPixel(bitsPerPixel);
-            ImageEncodingHelper.encodeRGBAsGrayScale(
-                  imageData, dataWidth, dataHeight, bitsPerPixel, boas);
-            imageData = boas.toByteArray();
-            if (bitsPerPixel == 1) {
-                //FS10 should generate a page seqment to avoid problems
-                imageObjectInfo.setCreatePageSegment(true);
-            }
-        }
-        imageObjectInfo.setData(imageData);
-
-        if (imageInfo != null) {
-            imageObjectInfo.setUri(imageInfo.getOriginalURI());
-        }
-
-        // create object area info
-        AFPObjectAreaInfo objectAreaInfo = new AFPObjectAreaInfo();
-        objectAreaInfo.setX(x);
-        objectAreaInfo.setY(y);
-        objectAreaInfo.setWidth(width);
-        objectAreaInfo.setHeight(height);
-
-        objectAreaInfo.setWidthRes(resolution);
-        objectAreaInfo.setHeightRes(resolution);
-
-        imageObjectInfo.setObjectAreaInfo(objectAreaInfo);
-
-        return imageObjectInfo;
-    }
-
     /**
      * Draws an AWT image into a BufferedImage using an AWT Graphics2D implementation
      *
     /** {@inheritDoc} */
     public boolean drawImage(Image img, int x, int y, int width, int height,
             ImageObserver observer) {
-
         // draw with AWT Graphics2D
         Dimension imageSize = new Dimension(width, height);
         BufferedImage bufferedImage = buildBufferedImage(imageSize);
         int imgWidth = img.getWidth();
         int imgHeight = img.getHeight();
 
-        AffineTransform at = paintingState.getData().getTransform();
         AffineTransform gat = gc.getTransform();
         int graphicsObjectHeight
             = graphicsObj.getObjectEnvironmentGroup().getObjectAreaDescriptor().getHeight();
-        int x = (int)Math.round(at.getTranslateX() + gat.getTranslateX());
-        int y = (int)Math.round(at.getTranslateY() - (gat.getTranslateY() - graphicsObjectHeight));
-        int width = (int)Math.round(imgWidth * gat.getScaleX());
-        int height = (int)Math.round(imgHeight * -gat.getScaleY());
+
+        double toMillipointFactor = UnitConv.IN2PT * 1000 / (double)paintingState.getResolution();
+        double x = gat.getTranslateX();
+        double y = -(gat.getTranslateY() - graphicsObjectHeight);
+        x = toMillipointFactor * x;
+        y = toMillipointFactor * y;
+        double w = toMillipointFactor * imgWidth * gat.getScaleX();
+        double h = toMillipointFactor * imgHeight * -gat.getScaleY();
+
+        AFPImageHandlerRenderedImage handler = new AFPImageHandlerRenderedImage();
+        ImageInfo imageInfo = new ImageInfo(null, null);
+        imageInfo.setSize(new ImageSize(
+                img.getWidth(), img.getHeight(), paintingState.getResolution()));
+        imageInfo.getSize().calcSizeFromPixels();
+        ImageRendered red = new ImageRendered(imageInfo, img, null);
+        Rectangle targetPos = new Rectangle(
+                (int)Math.round(x),
+                (int)Math.round(y),
+                (int)Math.round(w),
+                (int)Math.round(h));
+        AFPRenderingContext context = new AFPRenderingContext(null,
+                resourceManager, paintingState, fontInfo, null);
         try {
-            // get image object info
-            AFPImageObjectInfo imageObjectInfo
-                = createImageObjectInfo(img, x, y, width, height);
-            // create image resource
-            resourceManager.createObject(imageObjectInfo);
+            handler.handleImage(context, red, targetPos);
         } catch (IOException ioe) {
             handleIOException(ioe);
         }

src/java/org/apache/fop/afp/AFPPaintingState.java

     /** color image support */
     private boolean colorImages = false;
 
+    /** dithering quality setting (0.0f..1.0f) */
+    private float ditheringQuality;
+
     /** color image handler */
     private ColorConverter colorConverter = GrayScaleColorConverter.getInstance();
 
         return this.cmykImagesSupported;
     }
 
+    /**
+     * Gets the dithering quality setting to use when converting images to monochrome images.
+     * @return the dithering quality (a value between 0.0f and 1.0f)
+     */
+    public float getDitheringQuality() {
+        return this.ditheringQuality;
+    }
+
+    /**
+     * Sets the dithering quality setting to use when converting images to monochrome images.
+     * @param quality Defines the desired quality level for the conversion.
+     *                  Valid values: a value between 0.0f (fastest) and 1.0f (best)
+     */
+    public void setDitheringQuality(float quality) {
+        quality = Math.max(quality, 0.0f);
+        quality = Math.min(quality, 1.0f);
+        this.ditheringQuality = quality;
+    }
+
     /**
      * Sets the output/device resolution
      *

src/java/org/apache/fop/afp/modca/GraphicsDataDescriptor.java

         return data;
     }
 
-    private static final int ABS = 2;
-    private static final int IMGRES = 8;
+    private static final int ABS = 64;
+    private static final int IMGRES = 16;
 
     /**
      * Returns the window specification data

src/java/org/apache/fop/render/afp/AFPCustomizable.java

      */
     void setShadingMode(AFPShadingMode shadingMode);
 
+    /**
+     * Sets the dithering quality setting to use when converting images to monochrome images.
+     * @param quality Defines the desired quality level for the conversion.
+     *                  Valid values: a value between 0.0f (fastest) and 1.0f (best)
+     */
+    void setDitheringQuality(float quality);
+
     /**
      * Sets the output/device resolution
      *

src/java/org/apache/fop/render/afp/AFPDocumentHandler.java

 import org.apache.fop.render.afp.extensions.AFPElementMapping;
 import org.apache.fop.render.afp.extensions.AFPIncludeFormMap;
 import org.apache.fop.render.afp.extensions.AFPInvokeMediumMap;
-import org.apache.fop.render.afp.extensions.AFPPageSetup;
 import org.apache.fop.render.afp.extensions.AFPPageOverlay;
+import org.apache.fop.render.afp.extensions.AFPPageSetup;
 import org.apache.fop.render.intermediate.AbstractBinaryWritingIFDocumentHandler;
 import org.apache.fop.render.intermediate.IFDocumentHandler;
 import org.apache.fop.render.intermediate.IFDocumentHandlerConfigurator;
         paintingState.setCMYKImagesSupported(value);
     }
 
+    /** {@inheritDoc} */
+    public void setDitheringQuality(float quality) {
+        this.paintingState.setDitheringQuality(quality);
+    }
+
     /** {@inheritDoc} */
     public void setShadingMode(AFPShadingMode shadingMode) {
         this.shadingMode = shadingMode;

src/java/org/apache/fop/render/afp/AFPImageHandlerGraphics2D.java

 package org.apache.fop.render.afp;
 
 import java.awt.Rectangle;
+import java.awt.geom.AffineTransform;
 import java.io.IOException;
 
 import org.apache.xmlgraphics.image.loader.Image;
 
         setDefaultResourceLevel(graphicsObjectInfo, afpContext.getResourceManager());
 
+        AFPPaintingState paintingState = afpContext.getPaintingState();
+        paintingState.save(); // save
+        AffineTransform placement = new AffineTransform();
+        placement.translate(pos.x, pos.y);
+        paintingState.concatenate(placement);
+
         // Image content
         ImageGraphics2D imageG2D = (ImageGraphics2D)image;
         boolean textAsShapes = false; //TODO Make configurable
 
         // Create image
         afpContext.getResourceManager().createObject(graphicsObjectInfo);
+
+        paintingState.restore(); // resume
     }
 
     /** {@inheritDoc} */

src/java/org/apache/fop/render/afp/AFPImageHandlerRenderedImage.java

                 maxPixelSize *= 3; //RGB is maximum
             }
         }
+        float ditheringQuality = paintingState.getDitheringQuality();
         RenderedImage renderedImage = imageRendered.getRenderedImage();
 
         ImageInfo imageInfo = imageRendered.getInfo();
                     log.debug("Resample from " + intrinsicSize.getDimensionPx()
                             + " to " + resampledDim);
                 }
-                renderedImage = BitmapImageUtil.convertToMonochrome(renderedImage, resampledDim);
+                renderedImage = BitmapImageUtil.convertToMonochrome(renderedImage,
+                        resampledDim, ditheringQuality);
                 effIntrinsicSize = new ImageSize(
                         resampledDim.width, resampledDim.height, resolution);
+            } else if (ditheringQuality >= 0.5f) {
+                renderedImage = BitmapImageUtil.convertToMonochrome(renderedImage,
+                        intrinsicSize.getDimensionPx(), ditheringQuality);
             }
         }
 
         if (cm.hasAlpha()) {
             pixelSize -= 8;
         }
-        //TODO Add support for CMYK images
 
         byte[] imageData = null;
         ByteArrayOutputStream baos = new ByteArrayOutputStream();

src/java/org/apache/fop/render/afp/AFPRenderer.java

         paintingState.setCMYKImagesSupported(value);
     }
 
+    /** {@inheritDoc} */
+    public void setDitheringQuality(float quality) {
+        this.paintingState.setDitheringQuality(quality);
+    }
+
     /** {@inheritDoc} */
     public void setShadingMode(AFPShadingMode shadingMode) {
         this.shadingMode = shadingMode;

src/java/org/apache/fop/render/afp/AFPRendererConfigurator.java

             customizable.setBitsPerPixel(bitsPerPixel);
         }
 
+        String dithering = imagesCfg.getAttribute("dithering-quality", "medium");
+        float dq = 0.5f;
+        if (dithering.startsWith("min")) {
+            dq = 0.0f;
+        } else if (dithering.startsWith("max")) {
+            dq = 1.0f;
+        } else {
+            try {
+                dq = Float.parseFloat(dithering);
+            } catch (NumberFormatException nfe) {
+                //ignore and leave the default above
+            }
+        }
+        customizable.setDitheringQuality(dq);
+
         // native image support
         boolean nativeImageSupport = imagesCfg.getAttributeAsBoolean("native", false);
         customizable.setNativeImagesSupported(nativeImageSupport);

src/java/org/apache/fop/util/bitmap/BitmapImageUtil.java

      */
     public static final BufferedImage convertToMonochrome(RenderedImage img,
             Dimension targetDimension) {
+        return toBufferedImage(convertToMonochrome(img, targetDimension, 0.0f));
+    }
+
+    /**
+     * Converts an image to a monochrome 1-bit image. Optionally, the image can be scaled.
+     * @param img the image to be converted
+     * @param targetDimension the new target dimensions or null if no scaling is necessary
+     * @param quality Defines the desired quality level for the conversion.
+     *                  Valid values: a value between 0.0f (fastest) and 1.0f (best)
+     * @return the monochrome image
+     */
+    public static final RenderedImage convertToMonochrome(RenderedImage img,
+            Dimension targetDimension, float quality) {
+        if (!isMonochromeImage(img)) {
+            if (quality >= 0.5f) {
+                BufferedImage bi;
+                Dimension orgDim = new Dimension(img.getWidth(), img.getHeight());
+                if (targetDimension != null && !orgDim.equals(targetDimension)) {
+                    //Scale only before dithering
+                    ColorModel cm = img.getColorModel();
+                    BufferedImage tgt = new BufferedImage(cm,
+                            cm.createCompatibleWritableRaster(
+                                    targetDimension.width, targetDimension.height),
+                            cm.isAlphaPremultiplied(), null);
+                    transferImage(img, tgt);
+                    bi = tgt;
+                } else {
+                    bi = toBufferedImage(img);
+                }
+                //Now convert to monochrome (dithering if available)
+                MonochromeBitmapConverter converter = createDefaultMonochromeBitmapConverter();
+                if (quality >= 0.8f) {
+                    //Activates error diffusion if JAI is available
+                    converter.setHint("quality", Boolean.TRUE.toString());
+                    //Need to convert to grayscale first since otherwise, there may be encoding
+                    //problems later with the images JAI can generate.
+                    bi = convertToGrayscale(bi, targetDimension);
+                }
+                try {
+                    return converter.convertToMonochrome(bi);
+                } catch (Exception e) {
+                    //Provide a fallback if exotic formats are encountered
+                    bi = convertToGrayscale(bi, targetDimension);
+                    return converter.convertToMonochrome(bi);
+                }
+            }
+        }
         return convertAndScaleImage(img, targetDimension, BufferedImage.TYPE_BYTE_BINARY);
     }
 

status.xml

       documents. Example: the fix of marks layering will be such a case when it's done.
     -->
     <release version="FOP Trunk" date="TBD">
+      <action context="Renderers" dev="JM" type="fix">
+        AFP Output: Fixed positioning of Java2D-based images (when GOCA is enabled).
+      </action>
+      <action context="Renderers" dev="JM" type="add">
+        AFP Output: Added enhanced dithering functionality for images that are converted to
+        bi-level images.
+      </action>
       <action context="Renderers" dev="JM" type="fix">
         AFP Output: Fix for bitmap images inside an SVG or G2D graphic (printer errors) and
         positioning fix for bitmaps from G2D graphics.