package com.test;import java.awt.Dimension;import java.awt.Image;import java.awt.image.BufferedImage;import java.awt.image.PixelGrabber;import java.io.File;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import java.util.Iterator;import java.util.Locale;import javax.imageio.IIOImage;import javax.imageio.ImageIO;import javax.imageio.ImageWriteParam;import javax.imageio.ImageWriter;import javax.imageio.plugins.jpeg.JPEGImageWriteParam;import javax.imageio.stream.ImageOutputStream;public class ImageUtils {public static final int IMAGE_UNKNOWN = -1;public static final int IMAGE_JPEG = 0;public static final int IMAGE_PNG = 1;public static final int IMAGE_GIF = 2;public static BufferedImage resizeImage(String imgName, int type,int maxWidth, int maxHeight) {try {return resizeImage(ImageIO.read(new File(imgName)), type, maxWidth,maxHeight);} catch (IOException e) {e.printStackTrace();return null;}}public static BufferedImage resizeImage(BufferedImage image, int type,int maxWidth, int maxHeight) {Dimension largestDimension = new Dimension(maxWidth, maxHeight);// Original sizeint imageWidth = image.getWidth(null);int imageHeight = image.getHeight(null);float aspectRatio = (float) imageWidth / imageHeight;if (imageWidth > maxWidth || imageHeight > maxHeight) {if ((float) largestDimension.width / largestDimension.height > aspectRatio) {largestDimension.width = (int) Math.ceil(largestDimension.height * aspectRatio);} else {largestDimension.height = (int) Math.ceil(largestDimension.width / aspectRatio);}imageWidth = largestDimension.width;imageHeight = largestDimension.height;}return createHeadlessSmoothBufferedImage(image, type, imageWidth,imageHeight);}public static boolean saveImage(BufferedImage image, String toFileName,int type) {try {return ImageIO.write(image, type == IMAGE_JPEG ? "jpg" : "png",new File(toFileName));} catch (IOException e) {e.printStackTrace();return false;}}public static void saveCompressedImage(BufferedImage image,String toFileName, int type) {try {if (type == IMAGE_PNG) {throw new UnsupportedOperationException("PNG compression not implemented");}Iterator iter = ImageIO.getImageWritersByFormatName("jpg");ImageWriter writer;writer = (ImageWriter) iter.next();ImageOutputStream ios = ImageIO.createImageOutputStream(new File(toFileName));writer.setOutput(ios);ImageWriteParam iwparam = new JPEGImageWriteParam(Locale.getDefault());iwparam.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);iwparam.setCompressionQuality(0.7F);writer.write(null, new IIOImage(image, null, null), iwparam);ios.flush();writer.dispose();ios.close();} catch (IOException e) {e.printStackTrace();}}public static BufferedImage createHeadlessBufferedImage(BufferedImage image, int type, int width, int height) {if (type == ImageUtils.IMAGE_PNG && hasAlpha(image)) {type = BufferedImage.TYPE_INT_ARGB;} else {type = BufferedImage.TYPE_INT_RGB;}BufferedImage bi = new BufferedImage(width, height, type);for (int y = 0; y < height; y++) {for (int x = 0; x < width; x++) {bi.setRGB(x, y, image.getRGB(x * image.getWidth() / width, y* image.getHeight() / height));}}return bi;}public static BufferedImage createHeadlessSmoothBufferedImage(BufferedImage source, int type, int width, int height) {if (type == ImageUtils.IMAGE_PNG && hasAlpha(source)) {type = BufferedImage.TYPE_INT_ARGB;} else {type = BufferedImage.TYPE_INT_RGB;}BufferedImage dest = new BufferedImage(width, height, type);int sourcex;int sourcey;double scalex = (double) width / source.getWidth();double scaley = (double) height / source.getHeight();int x1;int y1;double xdiff;double ydiff;int rgb;int rgb1;int rgb2;for (int y = 0; y < height; y++) {sourcey = y * source.getHeight() / dest.getHeight();ydiff = scale(y, scaley) - sourcey;for (int x = 0; x < width; x++) {sourcex = x * source.getWidth() / dest.getWidth();xdiff = scale(x, scalex) - sourcex;x1 = Math.min(source.getWidth() - 1, sourcex + 1);y1 = Math.min(source.getHeight() - 1, sourcey + 1);rgb1 = getRGBInterpolation(source.getRGB(sourcex, sourcey),source.getRGB(x1, sourcey), xdiff);rgb2 = getRGBInterpolation(source.getRGB(sourcex, y1), source.getRGB(x1, y1), xdiff);rgb = getRGBInterpolation(rgb1, rgb2, ydiff);dest.setRGB(x, y, rgb);}}return dest;}private static double scale(int point, double scale) {return point / scale;}private static int getRGBInterpolation(int value1, int value2,double distance) {int alpha1 = (value1 & 0xFF000000) >>> 24;int red1 = (value1 & 0x00FF0000) >> 16;int green1 = (value1 & 0x0000FF00) >> 8;int blue1 = (value1 & 0x000000FF);int alpha2 = (value2 & 0xFF000000) >>> 24;int red2 = (value2 & 0x00FF0000) >> 16;int green2 = (value2 & 0x0000FF00) >> 8;int blue2 = (value2 & 0x000000FF);int rgb = ((int) (alpha1 * (1.0 - distance) + alpha2 * distance) << 24)| ((int) (red1 * (1.0 - distance) + red2 * distance) << 16)| ((int) (green1 * (1.0 - distance) + green2 * distance) << 8)| (int) (blue1 * (1.0 - distance) + blue2 * distance);return rgb;}public static boolean hasAlpha(Image image) {try {PixelGrabber pg = new PixelGrabber(image, 0, 0, 1, 1, false);pg.grabPixels();return pg.getColorModel().hasAlpha();} catch (InterruptedException e) {return false;}}public static void main(String[] args) {try {ImageIO.write(ImageUtils.resizeImage("d:/world.jpg", ImageUtils.IMAGE_JPEG, 300, 200), "JPEG", new FileOutputStream("d:/test.jpg"));} catch (FileNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();} }}
