Bugfix: alternative text not working in tagged PDF for TIFF images

git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/trunk@1124394 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/fop/render/pdf/AbstractPDFImageHandler.java

@@ -0,0 +1,69 @@
+/*
+ * 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.
+ */
+
+/* $Id$ */
+
+package org.apache.fop.render.pdf;
+
+import java.awt.Rectangle;
+import java.io.IOException;
+
+import org.apache.xmlgraphics.image.loader.Image;
+
+import org.apache.fop.pdf.PDFImage;
+import org.apache.fop.pdf.PDFXObject;
+import org.apache.fop.render.ImageHandler;
+import org.apache.fop.render.RenderingContext;
+import org.apache.fop.render.pdf.PDFLogicalStructureHandler.MarkedContentInfo;
+
+/**
+ * A partial implementation of a PDF-specific image handler, containing the code that is
+ * common between image flavors.
+ */
+abstract class AbstractPDFImageHandler implements ImageHandler {
+
+    /** {@inheritDoc} */
+    public void handleImage(RenderingContext context, Image image, Rectangle pos)
+            throws IOException {
+        PDFRenderingContext pdfContext = (PDFRenderingContext)context;
+        PDFContentGenerator generator = pdfContext.getGenerator();
+        PDFImage pdfimage = createPDFImage(image, image.getInfo().getOriginalURI());
+        PDFXObject xobj = generator.getDocument().addImage(
+                generator.getResourceContext(), pdfimage);
+
+        float x = (float)pos.getX() / 1000f;
+        float y = (float)pos.getY() / 1000f;
+        float w = (float)pos.getWidth() / 1000f;
+        float h = (float)pos.getHeight() / 1000f;
+        if (context.getUserAgent().isAccessibilityEnabled()) {
+            MarkedContentInfo mci = pdfContext.getMarkedContentInfo();
+            generator.placeImage(x, y, w, h, xobj, mci.tag, mci.mcid);
+        } else {
+            generator.placeImage(x, y, w, h, xobj);
+        }
+    }
+
+    /**
+     * Creates a PDF image object out of the given image.
+     *
+     * @param image an image
+     * @param xobjectKey a key for retrieval of the image from the document's XObject collection
+     * @return a suitable {@link PDFImage} implementation that can handle the flavour of
+     * the given image
+     */
+    abstract PDFImage createPDFImage(Image image, String xobjectKey);
+}

src/java/org/apache/fop/render/pdf/PDFImageHandlerRawCCITTFax.java

@@ -19,44 +19,26 @@
 
 package org.apache.fop.render.pdf;
 
-import java.awt.Rectangle;
-import java.io.IOException;
-
 import org.apache.xmlgraphics.image.loader.Image;
 import org.apache.xmlgraphics.image.loader.ImageFlavor;
 import org.apache.xmlgraphics.image.loader.impl.ImageRawCCITTFax;
 
 import org.apache.fop.pdf.PDFImage;
-import org.apache.fop.pdf.PDFXObject;
-import org.apache.fop.render.ImageHandler;
 import org.apache.fop.render.RenderingContext;
 
 /**
  * Image handler implementation which handles CCITT encoded images (CCITT fax group 3/4)
  * for PDF output.
  */
-public class PDFImageHandlerRawCCITTFax implements ImageHandler {
+public class PDFImageHandlerRawCCITTFax extends AbstractPDFImageHandler {
 
     private static final ImageFlavor[] FLAVORS = new ImageFlavor[] {
         ImageFlavor.RAW_CCITTFAX,
     };
 
-    /** {@inheritDoc} */
-    public void handleImage(RenderingContext context, Image image, Rectangle pos)
-                throws IOException {
-        PDFRenderingContext pdfContext = (PDFRenderingContext)context;
-        PDFContentGenerator generator = pdfContext.getGenerator();
-        ImageRawCCITTFax ccitt = (ImageRawCCITTFax)image;
-
-        PDFImage pdfimage = new ImageRawCCITTFaxAdapter(ccitt, image.getInfo().getOriginalURI());
-        PDFXObject xobj = generator.getDocument().addImage(
-                generator.getResourceContext(), pdfimage);
-
-        float x = (float)pos.getX() / 1000f;
-        float y = (float)pos.getY() / 1000f;
-        float w = (float)pos.getWidth() / 1000f;
-        float h = (float)pos.getHeight() / 1000f;
-        generator.placeImage(x, y, w, h, xobj);
+    @Override
+    PDFImage createPDFImage(Image image, String xobjectKey) {
+        return new ImageRawCCITTFaxAdapter((ImageRawCCITTFax) image, xobjectKey);
     }
 
     /** {@inheritDoc} */

src/java/org/apache/fop/render/pdf/PDFImageHandlerRawJPEG.java

@@ -19,56 +19,32 @@
 
 package org.apache.fop.render.pdf;
 
-import java.awt.Rectangle;
-import java.io.IOException;
-
 import org.apache.xmlgraphics.image.loader.Image;
 import org.apache.xmlgraphics.image.loader.ImageFlavor;
 import org.apache.xmlgraphics.image.loader.impl.ImageRawJPEG;
 
 import org.apache.fop.pdf.PDFImage;
-import org.apache.fop.pdf.PDFXObject;
-import org.apache.fop.render.ImageHandler;
 import org.apache.fop.render.RenderingContext;
-import org.apache.fop.render.pdf.PDFLogicalStructureHandler.MarkedContentInfo;
 
 /**
  * Image handler implementation which handles raw JPEG images for PDF output.
  */
-public class PDFImageHandlerRawJPEG implements ImageHandler {
+public class PDFImageHandlerRawJPEG extends AbstractPDFImageHandler {
 
     private static final ImageFlavor[] FLAVORS = new ImageFlavor[] {
         ImageFlavor.RAW_JPEG,
     };
 
-    /** {@inheritDoc} */
-    public void handleImage(RenderingContext context, Image image, Rectangle pos)
-                throws IOException {
-        PDFRenderingContext pdfContext = (PDFRenderingContext)context;
-        PDFContentGenerator generator = pdfContext.getGenerator();
-        ImageRawJPEG imageJPEG = (ImageRawJPEG)image;
-
-        PDFImage pdfimage = new ImageRawJPEGAdapter(imageJPEG, image.getInfo().getOriginalURI());
-        PDFXObject xobj = generator.getDocument().addImage(
-                generator.getResourceContext(), pdfimage);
-
-        float x = (float)pos.getX() / 1000f;
-        float y = (float)pos.getY() / 1000f;
-        float w = (float)pos.getWidth() / 1000f;
-        float h = (float)pos.getHeight() / 1000f;
-        if (context.getUserAgent().isAccessibilityEnabled()) {
-            MarkedContentInfo mci = pdfContext.getMarkedContentInfo();
-            generator.placeImage(x, y, w, h, xobj, mci.tag, mci.mcid);
-        } else {
-            generator.placeImage(x, y, w, h, xobj);
-        }
-    }
-
     /** {@inheritDoc} */
     public int getPriority() {
         return 100;
     }
 
+    @Override
+    PDFImage createPDFImage(Image image, String xobjectKey) {
+        return new ImageRawJPEGAdapter((ImageRawJPEG) image, xobjectKey);
+    }
+
     /** {@inheritDoc} */
     public Class getSupportedImageClass() {
         return ImageRawJPEG.class;

src/java/org/apache/fop/render/pdf/PDFImageHandlerRenderedImage.java

@@ -19,50 +19,26 @@
 
 package org.apache.fop.render.pdf;
 
-import java.awt.Rectangle;
-import java.io.IOException;
-
 import org.apache.xmlgraphics.image.loader.Image;
 import org.apache.xmlgraphics.image.loader.ImageFlavor;
 import org.apache.xmlgraphics.image.loader.impl.ImageRendered;
 
 import org.apache.fop.pdf.PDFImage;
-import org.apache.fop.pdf.PDFXObject;
-import org.apache.fop.render.ImageHandler;
 import org.apache.fop.render.RenderingContext;
-import org.apache.fop.render.pdf.PDFLogicalStructureHandler.MarkedContentInfo;
 
 /**
  * Image handler implementation which handles RenderedImage instances for PDF output.
  */
-public class PDFImageHandlerRenderedImage implements ImageHandler {
+public class PDFImageHandlerRenderedImage extends AbstractPDFImageHandler {
 
     private static final ImageFlavor[] FLAVORS = new ImageFlavor[] {
         ImageFlavor.BUFFERED_IMAGE,
         ImageFlavor.RENDERED_IMAGE
     };
 
-    /** {@inheritDoc} */
-    public void handleImage(RenderingContext context, Image image, Rectangle pos)
-                throws IOException {
-        PDFRenderingContext pdfContext = (PDFRenderingContext)context;
-        PDFContentGenerator generator = pdfContext.getGenerator();
-        ImageRendered imageRend = (ImageRendered)image;
-
-        PDFImage pdfimage = new ImageRenderedAdapter(imageRend, image.getInfo().getOriginalURI());
-        PDFXObject xobj = generator.getDocument().addImage(
-                generator.getResourceContext(), pdfimage);
-
-        float x = (float)pos.getX() / 1000f;
-        float y = (float)pos.getY() / 1000f;
-        float w = (float)pos.getWidth() / 1000f;
-        float h = (float)pos.getHeight() / 1000f;
-        if (context.getUserAgent().isAccessibilityEnabled()) {
-            MarkedContentInfo mci = pdfContext.getMarkedContentInfo();
-            generator.placeImage(x, y, w, h, xobj, mci.tag, mci.mcid);
-        } else {
-            generator.placeImage(x, y, w, h, xobj);
-        }
+    @Override
+    PDFImage createPDFImage(Image image, String xobjectKey) {
+        return new ImageRenderedAdapter((ImageRendered) image, xobjectKey);
     }
 
     /** {@inheritDoc} */

status.xml

@@ -59,6 +59,9 @@
       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="VH" type="fix">
+        Bugfix: alternative text not working in tagged PDF for TIFF images.
+      </action>
       <action context="Renderers" dev="PH" type="fix" fixes-bug="50909">
         Fixed io exception in MODCAParser caused by the improper use of mark() and reset() on the
         MODCA data input stream.  Added unit test. </action>