Java图片处理 (文字水印、图片水印、缩放、补白)代码实例

package com.hmw.picMark;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;/** * 图片工具类， 图片水印，文字水印，缩放，补白等 * @author Carl He */public final class ImageUtils {	/**图片格式：JPG*/	private static final String PICTRUE_FORMATE_JPG = "jpg";		private ImageUtils(){}	/**	 * 添加图片水印	 * @param targetImg 目标图片路径，如：C://myPictrue//1.jpg	 * @param waterImg 水印图片路径，如：C://myPictrue//logo.png	 * @param x 水印图片距离目标图片左侧的偏移量，如果x<0, 则在正中间	 * @param y 水印图片距离目标图片上侧的偏移量，如果y<0, 则在正中间	 * @param alpha 透明度(0.0 -- 1.0, 0.0为完全透明，1.0为完全不透明)	 */	public final static void pressImage(String targetImg, String waterImg, int x, int y, float alpha) {			try {				File file = new File(targetImg);				Image image = ImageIO.read(file);				int width = image.getWidth(null);				int height = image.getHeight(null);				BufferedImage bufferedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);				Graphics2D g = bufferedImage.createGraphics();				g.drawImage(image, 0, 0, width, height, null);							Image waterImage = ImageIO.read(new File(waterImg));	// 水印文件				int width_1 = waterImage.getWidth(null);				int height_1 = waterImage.getHeight(null);				g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, alpha));								int widthDiff = width - width_1;				int heightDiff = height - height_1;				if(x < 0){					x = widthDiff / 2;				}else if(x > widthDiff){					x = widthDiff;				}				if(y < 0){					y = heightDiff / 2;				}else if(y > heightDiff){					y = heightDiff;				}				g.drawImage(waterImage, x, y, width_1, height_1, null); // 水印文件结束				g.dispose();				ImageIO.write(bufferedImage, PICTRUE_FORMATE_JPG, file);			} catch (IOException e) {				e.printStackTrace();			}	}	/**	 * 添加文字水印	 * @param targetImg 目标图片路径，如：C://myPictrue//1.jpg	 * @param pressText 水印文字， 如：中国证券网	 * @param fontName 字体名称，	如：宋体	 * @param fontStyle 字体样式，如：粗体和斜体(Font.BOLD|Font.ITALIC)	 * @param fontSize 字体大小，单位为像素	 * @param color 字体颜色	 * @param x 水印文字距离目标图片左侧的偏移量，如果x<0, 则在正中间	 * @param y 水印文字距离目标图片上侧的偏移量，如果y<0, 则在正中间	 * @param alpha 透明度(0.0 -- 1.0, 0.0为完全透明，1.0为完全不透明)	 */	public static void pressText(String targetImg, String pressText, String fontName, int fontStyle, int fontSize, Color color, int x, int y, float alpha) {		try {			File file = new File(targetImg);						Image image = ImageIO.read(file);			int width = image.getWidth(null);			int height = image.getHeight(null);			BufferedImage bufferedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);			Graphics2D g = bufferedImage.createGraphics();			g.drawImage(image, 0, 0, width, height, null);			g.setFont(new Font(fontName, fontStyle, fontSize));			g.setColor(color);			g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, alpha));						int width_1 = fontSize * getLength(pressText);			int height_1 = fontSize;			int widthDiff = width - width_1;			int heightDiff = height - height_1;			if(x < 0){				x = widthDiff / 2;			}else if(x > widthDiff){				x = widthDiff;			}			if(y < 0){				y = heightDiff / 2;			}else if(y > heightDiff){				y = heightDiff;			}						g.drawString(pressText, x, y + height_1);			g.dispose();			ImageIO.write(bufferedImage, PICTRUE_FORMATE_JPG, file);		} catch (Exception e) {			e.printStackTrace();		}	}		/**	 * 获取字符长度，一个汉字作为 1 个字符, 一个英文字母作为 0.5 个字符	 * @param text	 * @return 字符长度，如：text="中国",返回 2；text="test",返回 2；text="中国ABC",返回 4.	 */	public static int getLength(String text) {		int textLength = text.length();		int length = textLength;		for (int i = 0; i < textLength; i++) {			if (String.valueOf(text.charAt(i)).getBytes().length > 1) {				length++;			}		}		return (length % 2 == 0) ? length / 2 : length / 2 + 1;	}	/**	 * 图片缩放	 * @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; //缩放比例        File f = new File(filePath);        BufferedImage bi = ImageIO.read(f);        Image itemp = bi.getScaledInstance(width, height, BufferedImage.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);          else           g.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("C://pic//jpg", "C://pic//test.gif", 5000, 5000, 0f);		pressText("C://pic//jpg", "旺仔之印", "宋体", Font.BOLD|Font.ITALIC, 20, Color.BLACK, 0, 0, 8f);		resize("C://pic//4.jpg", 1000, 500, true);	}}