NIHVIVO-1208 Cleaned things up a bit - ready to give up, for now at least. Still works for JPEG, but not for GIF.

webapp/src/edu/cornell/mannlib/vitro/webapp/controller/freemarker/ImageUploadHelper.java

@@ -393,7 +393,7 @@ public class ImageUploadHelper {
 	 * is written as a simple log message.
 	 * </p>
 	 */
-	private static class NonNoisyImagingListener implements ImagingListener {
+	static class NonNoisyImagingListener implements ImagingListener {
 		@Override
 		public boolean errorOccurred(String message, Throwable thrown,
 				Object where, boolean isRetryable) throws RuntimeException {

webapp/src/edu/cornell/mannlib/vitro/webapp/controller/freemarker/ImageUploadThumbnailer.java

@@ -7,7 +7,6 @@ import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
-import java.util.Arrays;
 
 import javax.media.jai.InterpolationBilinear;
 import javax.media.jai.RenderedOp;
@@ -28,8 +27,15 @@ import edu.cornell.mannlib.vitro.webapp.controller.freemarker.ImageUploadControl
 /**
  * Crop the main image as specified, and scale it to the correct size for a
  * thumbnail.
+ * 
+ * The JAI library has a problem when writing a JPEG from a source image with an
+ * alpha channel (transparency). The colors come out inverted. We throw in a
+ * step that will remove transparency from a PNG, but it won't touch a GIF.
  */
 public class ImageUploadThumbnailer {
+	/** If an image has 3 color bands and 1 alpha band, we want these. */
+	private static final int[] COLOR_BAND_INDEXES = new int[] { 0, 1, 2 };
+
 	private static final Log log = LogFactory
 			.getLog(ImageUploadThumbnailer.class);
 
@@ -69,11 +75,20 @@ public class ImageUploadThumbnailer {
 
 	private RenderedOp makeImageOpaque(RenderedOp image) {
 		ColorModel colorModel = image.getColorModel();
+
 		if (!colorModel.hasAlpha()) {
+			// The image is already opaque.
 			return image;
 		}
-		return BandSelectDescriptor.create(image, figureBandIndices(image),
-				null);
+
+		if (image.getNumBands() == 4) {
+			// The image has a separate alpha channel. Drop the alpha channel.
+			return BandSelectDescriptor.create(image, COLOR_BAND_INDEXES, null);
+		}
+
+		// Don't know how to handle it. Probably a GIF with a transparent
+		// background. Give up.
+		return image;
 	}
 
 	private RenderedOp cropImage(RenderedOp image, CropRectangle crop) {
@@ -104,18 +119,6 @@ public class ImageUploadThumbnailer {
 		return bytes.toByteArray();
 	}
 
-	/** Build an array holding the indexes of the color bands in this image. */
-	private int[] figureBandIndices(RenderedOp image) {
-		int howMany = Math.min(image.getColorModel().getNumColorComponents(),
-				image.getNumBands());
-		int[] bandIndices = new int[howMany];
-		for (int i = 0; i < bandIndices.length; i++) {
-			bandIndices[i] = i;
-		}
-		log.debug("Selecting these bands: " + Arrays.toString(bandIndices));
-		return bandIndices;
-	}
-
 	private CropRectangle limitCropRectangleToImageBounds(RenderedOp image,
 			CropRectangle crop) {
 		log.debug("Generating a thumbnail, initial crop info: " + crop);

webapp/test/edu/cornell/mannlib/vitro/webapp/controller/freemarker/ImageUploaderThumbnailerTester.java

@@ -0,0 +1,135 @@
+/* $This file is distributed under the terms of the license in /doc/license.txt$ */
+
+package edu.cornell.mannlib.vitro.webapp.controller.freemarker;
+
+import static edu.cornell.mannlib.vitro.webapp.controller.freemarker.ImageUploadController.THUMBNAIL_HEIGHT;
+import static edu.cornell.mannlib.vitro.webapp.controller.freemarker.ImageUploadController.THUMBNAIL_WIDTH;
+
+import java.awt.Frame;
+import java.awt.GridLayout;
+import java.awt.event.WindowAdapter;
+import java.awt.event.WindowEvent;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+import javax.media.jai.JAI;
+import javax.media.jai.RenderedOp;
+import javax.media.jai.operator.StreamDescriptor;
+import javax.media.jai.widget.ImageCanvas;
+
+import org.apache.log4j.Level;
+import org.apache.log4j.Logger;
+
+import com.sun.media.jai.codec.MemoryCacheSeekableStream;
+
+import edu.cornell.mannlib.vitro.webapp.controller.freemarker.ImageUploadHelper.NonNoisyImagingListener;
+
+/**
+ * This is not a unit test, so it is not named BlahBlahTest.
+ * 
+ * Instead, it's a test harness that creates thumbnails and writes them to
+ * files, while also displaying them in a window on the screen. It takes human
+ * intervention to evaluate.
+ * 
+ * This is especially true because the images on the screen look color-correct,
+ * but when viewed in the browser, they might not be.
+ */
+public class ImageUploaderThumbnailerTester extends Frame {
+	static {
+		JAI.getDefaultInstance().setImagingListener(
+				new NonNoisyImagingListener());
+	}
+
+	/** Big enough to hold the JPEG file, certainly. */
+	private final static int BUFFER_SIZE = 200 * 200 * 4;
+
+	private final static ImageCropData[] THUMBNAIL_DATA = new ImageCropData[] {
+			new ImageCropData("/Users/jeb228/Pictures/JimBlake_20010915.jpg",
+					50, 50, 115),
+			new ImageCropData("/Users/jeb228/Pictures/brazil_collab.png", 600,
+					250, 400),
+			new ImageCropData("/Users/jeb228/Pictures/wheel.png", 0, 0, 195),
+			new ImageCropData("/Users/jeb228/Pictures/DSC04203w-trans.gif",
+					400, 1200, 800) };
+
+	private final ImageUploadThumbnailer thumbnailer = new ImageUploadThumbnailer(
+			THUMBNAIL_HEIGHT, THUMBNAIL_WIDTH);
+
+	private ImageUploaderThumbnailerTester() {
+		setTitle("Alpha Killer Test");
+		addWindowListener(new CloseWindowListener());
+		setLayout(createLayout());
+		for (ImageCropData icd : THUMBNAIL_DATA) {
+			try {
+				InputStream mainStream = new FileInputStream(icd.filename);
+				File thumbFile = writeToTempFile(thumbnailer.cropAndScale(
+						mainStream, icd.crop));
+				System.out.println(thumbFile.getAbsolutePath());
+
+				MemoryCacheSeekableStream thumbFileStream = new MemoryCacheSeekableStream(
+						new FileInputStream(thumbFile));
+				RenderedOp thumbImage = StreamDescriptor.create(
+						thumbFileStream, null, null);
+				add(new ImageCanvas(thumbImage));
+			} catch (Exception e) {
+				e.printStackTrace();
+			}
+		}
+		pack();
+		setVisible(true);
+	}
+
+	/**
+	 * @param thumbStream
+	 * @return
+	 * @throws IOException
+	 * @throws FileNotFoundException
+	 */
+	private File writeToTempFile(InputStream thumbStream) throws IOException,
+			FileNotFoundException {
+		File thumbFile = File.createTempFile("ImageUploaderThumbnailerTester",
+				"");
+		OutputStream imageOutputStream = new FileOutputStream(thumbFile);
+		byte[] buffer = new byte[BUFFER_SIZE];
+		int howMany = thumbStream.read(buffer);
+		imageOutputStream.write(buffer, 0, howMany);
+		imageOutputStream.close();
+		return thumbFile;
+	}
+
+	private GridLayout createLayout() {
+		GridLayout layout = new GridLayout(1, THUMBNAIL_DATA.length);
+		layout.setHgap(10);
+		return layout;
+	}
+
+	public static void main(String[] args) {
+		Logger.getLogger(ImageUploadThumbnailer.class).setLevel(Level.DEBUG);
+		new ImageUploaderThumbnailerTester();
+	}
+
+	private static class ImageCropData {
+		final String filename;
+		final ImageUploadController.CropRectangle crop;
+
+		ImageCropData(String filename, int x, int y, int size) {
+			this.filename = filename;
+			this.crop = new ImageUploadController.CropRectangle(x, y, size,
+					size);
+		}
+	}
+
+	private class CloseWindowListener extends WindowAdapter {
+		@Override
+		public void windowClosing(WindowEvent e) {
+			setVisible(false);
+			dispose();
+			System.exit(0);
+		}
+	}
+}