java图片文字水印、图片水印、缩放、补白处理

import java.awt.AlphaComposite;import java.awt.Color;import java.awt.Font;import java.awt.Graphics2D;import java.awt.Image;import java.awt.geom.AffineTransform;import java.awt.image.AffineTransformOp;import java.awt.image.BufferedImage;import java.io.File;import java.io.IOException;import javax.imageio.ImageIO;/** * @author Eric Xu * */public final class ImageUtils {/** * 图片水印 * @param pressImg 水印图片 * @param targetImg 目标图片 * @param x 修正值 默认在中间 * @param y 修正值 默认在中间 * @param alpha 透明度 */public final static void pressImage(String pressImg, String targetImg, int x, int y, float alpha) {try {File img = new File(targetImg);Image src = ImageIO.read(img);int wideth = src.getWidth(null);int height = src.getHeight(null);BufferedImage image = new BufferedImage(wideth, height, BufferedImage.TYPE_INT_RGB);Graphics2D g = image.createGraphics();g.drawImage(src, 0, 0, wideth, height, null);//水印文件Image src_biao = ImageIO.read(new File(pressImg));int wideth_biao = src_biao.getWidth(null);int height_biao = src_biao.getHeight(null);g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, alpha));g.drawImage(src_biao, (wideth - wideth_biao) / 2, (height - height_biao) / 2, wideth_biao, height_biao, null);//水印文件结束g.dispose();ImageIO.write((BufferedImage) image, "jpg", img);} catch (Exception e) {e.printStackTrace();}}/** * 文字水印 * @param pressText 水印文字 * @param targetImg 目标图片 * @param fontName 字体名称 * @param fontStyle 字体样式 * @param color 字体颜色 * @param fontSize 字体大小 * @param x 修正值 * @param y 修正值 * @param alpha 透明度 */public static void pressText(String pressText, String targetImg, String fontName, int fontStyle, Color color, int fontSize, int x, int y, float alpha) {try {File img = new File(targetImg);Image src = ImageIO.read(img);int width = src.getWidth(null);int height = src.getHeight(null);BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);Graphics2D g = image.createGraphics();g.drawImage(src, 0, 0, width, height, null);g.setColor(color);g.setFont(new Font(fontName, fontStyle, fontSize));g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, alpha));g.drawString(pressText, (width - (getLength(pressText) * fontSize)) / 2 + x, (height - fontSize) / 2 + y);g.dispose();ImageIO.write((BufferedImage) image, "jpg", img);} catch (Exception e) {e.printStackTrace();}}/** * 缩放 * @param filePath 图片路径 * @param height 高度 * @param width 宽度 * @param bb 比例不对时是否需要补白 */public static void resize(String filePath, int height, int width, boolean bb) {try {double ratio = 0.0; //缩放比例 File f = new File(filePath);BufferedImage bi = ImageIO.read(f);Image itemp = bi.getScaledInstance(width, height, bi.SCALE_SMOOTH);//计算比例if ((bi.getHeight() > height) || (bi.getWidth() > width)) {if (bi.getHeight() > bi.getWidth()) {ratio = (new Integer(height)).doubleValue() / bi.getHeight();} else {ratio = (new Integer(width)).doubleValue() / bi.getWidth();}AffineTransformOp op = new AffineTransformOp(AffineTransform.getScaleInstance(ratio, ratio), null);itemp = op.filter(bi, null);}if (bb) {BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);Graphics2D g = image.createGraphics();g.setColor(Color.white);g.fillRect(0, 0, width, height);if (width == itemp.getWidth(null))g.drawImage(itemp, 0, (height - itemp.getHeight(null)) / 2, itemp.getWidth(null), itemp.getHeight(null), Color.white, null);elseg.drawImage(itemp, (width - itemp.getWidth(null)) / 2, 0, itemp.getWidth(null), itemp.getHeight(null), Color.white, null);g.dispose();itemp = image;}ImageIO.write((BufferedImage) itemp, "jpg", f);} catch (IOException e) {e.printStackTrace();}}public static void main(String[] args) throws IOException {pressImage("G:\\imgtest\\sy.jpg", "G:\\imgtest\\test1.jpg", 0, 0, 0.5f);pressText("我是文字水印", "G:\\imgtest\\test1.jpg", "黑体", 36, Color.white, 80, 0, 0, 0.3f);resize("G:\\imgtest\\test1.jpg", 500, 500, true);}public static int getLength(String text) {int length = 0;for (int i = 0; i < text.length(); i++) {if (new String(text.charAt(i) + "").getBytes().length > 1) {length += 2;} else {length += 1;}}return length / 2;}}

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