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-600 * @param waterImg 水印图片路径，如：C://myPictrue//logo.png-600 * @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  widthDiff){ x = widthDiff; } 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-600 * @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<strong style="color:transparent">来源gao@daima#com搞(%代@#码@网</strong> = 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  widthDiff){ x = widthDiff; } 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  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-600", 1000, 500, true); } }