+ private static final long serialVersionUID = -4156533490858298387L;
+ /**
+ * Picture dimensions.
+ */
+ private Dimension dimensions;
+
+ public Picture(final File parentDirectory, final String fileName)
+ throws Exception {
+ super(parentDirectory, fileName);
+ }
+
+ private static void ensureNonzeroImageArea(final java.awt.Dimension result) {
+ if (result.width < 1)
+ result.width = 1;
+ if (result.height < 1)
+ result.height = 1;
+ }
+
+ /**
+ * Actual returned target thumbnail size will be adjusted from desired one
+ * by attempting to generate as large as possible thumbnail, while not
+ * exceeding provided thumbnail width and height, and preserving aspect
+ * ratio of original image.
+ */
+ private static java.awt.Dimension getTargetThumbnailDimension(
+ final java.awt.Dimension originalImageDimension,
+ final java.awt.Dimension desiredTargetDimension) {
+
+ final double thumbWidthToHeightRatio = (double) desiredTargetDimension.width
+ / (double) desiredTargetDimension.height;
+ final double inputImageWidthToHeightRatio = (double) originalImageDimension.width
+ / (double) originalImageDimension.height;
+
+ if (thumbWidthToHeightRatio < inputImageWidthToHeightRatio) {
+
+ final java.awt.Dimension result = new java.awt.Dimension(
+ desiredTargetDimension.width,
+ (int) (desiredTargetDimension.width / inputImageWidthToHeightRatio));
+
+ ensureNonzeroImageArea(result);
+
+ return result;
+ } else {
+
+ final java.awt.Dimension result = new java.awt.Dimension(
+ (int) (desiredTargetDimension.height * inputImageWidthToHeightRatio),
+ desiredTargetDimension.height);
+
+ ensureNonzeroImageArea(result);
+
+ return result;
+ }
+ }
+
+ /**
+ * Propose list of thumbnail dimensions.
+ */
+ public static List<Dimension> getThumbnailDimensions(Dimension current) {
+ final ArrayList<Dimension> result = new ArrayList<>();
+ result.add(current);
+
+ while (current.getArea() > 1000000) {
+ current = current.getScaled(0.5d);
+ result.add(current);
+ }
+
+ return result;
+
+ }
+
+ public static void makeThumbnail(final File inputFile,
+ final File outputFile,
+ final java.awt.Dimension preferredTargetDimensions) {
+
+ try {
+
+ final BufferedImage inputImage = getBufferedImage(inputFile);
+
+ final java.awt.Dimension sourceImageDimension = new java.awt.Dimension(
+ inputImage.getWidth(), inputImage.getHeight());
+
+ final java.awt.Dimension targetDimensions = getTargetThumbnailDimension(
+ sourceImageDimension, preferredTargetDimensions);
+
+ final OutputStream out = new FileOutputStream(outputFile);
+
+ final Image scaledImage = scaleImage(inputImage,
+ targetDimensions.width, targetDimensions.height);
+
+ final BufferedImage bufferedImage = new BufferedImage(
+ scaledImage.getWidth(null), scaledImage.getHeight(null),
+ BufferedImage.TYPE_INT_RGB);
+
+ final Graphics2D g = bufferedImage.createGraphics();
+ g.drawImage(scaledImage, 0, 0, null);
+ g.dispose();
+
+ ImageIO.write(bufferedImage, "jpg", out);
+ out.close();