NIHVIVO-161 Compensate for an image that was reduced for display.

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

@@ -536,13 +536,28 @@ public class ImageUploadController extends FreeMarkerHttpServlet {
 		final int height;
 		final int width;
 
-		private CropRectangle(int x, int y, int height, int width) {
+		CropRectangle(int x, int y, int height, int width) {
 			this.x = x;
 			this.y = y;
 			this.height = height;
 			this.width = width;
 		}
 
+		/** Produce a new crop rectangle that compensates for scaling. */
+		public CropRectangle unscale(float scale) {
+			int newX = (int) (x / scale);
+			int newY = (int) (y / scale);
+			int newHeight = (int) (height / scale);
+			int newWidth = (int) (width / scale);
+			return new CropRectangle(newX, newY, newHeight, newWidth);
+		}
+
+		@Override
+		public String toString() {
+			return "CropRectangle[x=" + x + ", y=" + y + ", w=" + width
+					+ ", h=" + height + "]";
+		}
+
 	}
 
 	/**

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

@@ -28,6 +28,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
 import edu.cornell.mannlib.vitro.webapp.beans.Individual;
+import edu.cornell.mannlib.vitro.webapp.controller.freemarker.ImageUploadController.CropRectangle;
 import edu.cornell.mannlib.vitro.webapp.controller.freemarker.ImageUploadController.Dimensions;
 import edu.cornell.mannlib.vitro.webapp.controller.freemarker.ImageUploadController.UserMistakeException;
 import edu.cornell.mannlib.vitro.webapp.dao.WebappDaoFactory;
@@ -42,6 +43,12 @@ import edu.cornell.mannlib.vitro.webapp.filestorage.uploadrequest.FileUploadServ
 public class ImageUploadHelper {
 	private static final Log log = LogFactory.getLog(ImageUploadHelper.class);
 
+	/**
+	 * If the main image is larger than this, it will be displayed at reduced
+	 * scale.
+	 */
+	public static final int MAXIMUM_IMAGE_DISPLAY_WIDTH = 500;
+
 	/** Recognized file extensions mapped to MIME-types. */
 	private static final Map<String, String> RECOGNIZED_FILE_TYPES = createFileTypesMap();
 
@@ -325,9 +332,12 @@ public class ImageUploadHelper {
 	 * width, height).
 	 */
 	private InputStream scaleImageForThumbnail(InputStream source,
-			ImageUploadController.CropRectangle crop) throws IOException {
+			CropRectangle crop) throws IOException {
 		BufferedImage bsrc = ImageIO.read(source);
 
+		// If the image was displayed in reduced form, adjust the crop info.
+		crop = adjustForScaledImageDisplay(bsrc.getWidth(), crop);
+
 		// Insure that x and y fall within the image dimensions.
 		int x = Math.max(0, Math.min(bsrc.getWidth(), Math.abs(crop.x)));
 		int y = Math.max(0, Math.min(bsrc.getHeight(), Math.abs(crop.y)));
@@ -340,10 +350,8 @@ public class ImageUploadHelper {
 		double scaleWidth = ((double) THUMBNAIL_WIDTH) / ((double) w);
 		double scaleHeight = ((double) THUMBNAIL_HEIGHT) / ((double) h);
 
-		log.debug("Generating a thumbnail, initial crop info: " + crop.x + ", "
+		log.debug("Generating a thumbnail, initial crop info: " + crop);
-				+ crop.y + ", " + crop.width + ", " + crop.height);
+		log.debug("Generating a thumbnail, bounded crop info: " + crop);
-		log.debug("Generating a thumbnail, bounded crop info: " + x + ", " + y
-				+ ", " + w + ", " + h);
 		log.debug("Generating a thumbnail, scales: " + scaleWidth + ", "
 				+ scaleHeight);
 
@@ -364,6 +372,24 @@ public class ImageUploadHelper {
 		return new ByteArrayInputStream(buffer.toByteArray());
 	}
 
+	/**
+	 * If the source image was too big to fit in the page, then it was displayed
+	 * at a reduced scale. The crop values must expand to apply to the
+	 * full-sized image.
+	 */
+	private CropRectangle adjustForScaledImageDisplay(int imageWidth,
+			CropRectangle crop) {
+		if (imageWidth <= MAXIMUM_IMAGE_DISPLAY_WIDTH) {
+			return crop;
+		}
+
+		float displayScale = ((float) MAXIMUM_IMAGE_DISPLAY_WIDTH)
+				/ ((float) imageWidth);
+		log.debug("Generating a thumbnail, unscaled crop info: " + crop
+				+ ", displayScale=" + displayScale);
+		return crop.unscale(displayScale);
+	}
+
 	/**
 	 * Find out how big the main image is.
 	 */