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java图片操作工具，包含以下类：- AlphaComposite- Color- Font- Graphics- Graphics2D- Image- Rectangle
图片操作工具
package cn.reinforce.plugin.util;
import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Rectangle;
import java.awt.Toolkit;
import java.awt.color.ColorSpace;
import java.awt.image.BufferedImage;
import java.awt.image.ColorConvertOp;
import java.awt.image.CropImageFilter;
import java.awt.image.FilteredImageSource;
import java.awt.image.ImageFilter;
import java.io.File;
import java.io.IOException;
import java.util.Iterator;
import javax.imageio.ImageIO;
import javax.imageio.ImageReadParam;
import javax.imageio.ImageReader;
import javax.imageio.stream.ImageInputStream;
import org.apache.log4j.Logger;
import com.mortennobel.imagescaling.ResampleOp;
/**
* 图片处理工具类：
* 功能：缩放图像、切割图像、图像类型转换、彩色转黑白、文字水印、图片水印等
*
* 依赖：
*
*
com.mortennobel
*
java-image-scaling
*
0.8.6
*
*
* @author 幻幻Fate
* @create 2016-09-06
* @since 1.0.0
*
*/
public class ImageUtil {
private static final Logger log = Logger.getLogger(ImageUtil.class);
/**
* 几种常见的图片格式
*/
public static final String IMAGE_TYPE_GIF = "gif";// 图形交换格式
public static final String IMAGE_TYPE_JPG = "jpg";// 联合照片专家组
public static final String IMAGE_TYPE_JPEG = "jpeg";// 联合照片专家组
public static final String IMAGE_TYPE_BMP = "bmp";// 英文Bitmap（位图）的简写，它是Windows操作系统中的标准图像文件格式
public static final String IMAGE_TYPE_PNG = "png";// 可移植网络图形
public static final String IMAGE_TYPE_PSD = "psd";// Photoshop的专用格式Photoshop
private ImageUtil() {
super();
}
/**
* 按文件名判断是否是图片
* @param type
* @return
*/
public static boolean isImage(String type){
return IMAGE_TYPE_BMP.equals(type)||IMAGE_TYPE_JPG.equals(type)||IMAGE_TYPE_JPEG.equals(type)||IMAGE_TYPE_GIF.equals(type)||IMAGE_TYPE_PNG.equals(type);
}
/**
* 重新设置图片大小
* @param originalFile
* @param resizedFile
* @param newWidth
* @param newHeight
* @param quality
*/
public static void resize(File originalFile, File resizedFile,
int newWidth, int newHeight, float quality) {
try {
BufferedImage inputBufImage = ImageIO.read(originalFile);
ResampleOp resampleOp = new ResampleOp(newWidth, newHeight);// 转换
BufferedImage rescaledTomato = resampleOp.filter(inputBufImage,
null);
ImageIO.write(rescaledTomato, IMAGE_TYPE_PNG, resizedFile);
} catch (IOException e) {
log.error("图片操作失败", e);
}
}
/**
* 图像切割(按指定起点坐标和宽高切割)
*
* @param srcImageFile
* 源图像地址
* @param result
* 切片后的图像地址
* @param x
* 目标切片起点坐标X
* @param y
* 目标切片起点坐标Y
* @param width
* 目标切片宽度
* @param height
* 目标切片高度
* @throws IOException
*/
public static void cut(File srcImageFile, File result, int x, int y,
int width, int height) {
ImageInputStream iis = null;
try {
iis = ImageIO.createImageInputStream(srcImageFile);
Iterator
iterator = ImageIO.getImageReaders(iis);
ImageReader reader = (ImageReader) iterator.next();
reader.setInput(iis, true);
ImageReadParam param = reader.getDefaultReadParam();
Rectangle rectangle = new Rectangle(x, y, width, height);
param.setSourceRegion(rectangle);
BufferedImage bi = reader.read(0, param);
ImageIO.write(bi, IMAGE_TYPE_PNG, result);
} catch (Exception e) {
log.error("图片操作失败", e);
} finally {
if (iis != null) {
try {
iis.close();
} catch (IOException e) {
log.error("文件关闭失败", e);
}
}
}
}
/**
* 图像切割（指定切片的宽度和高度）
*
* @param srcImageFile
* 源图像地址
* @param descDir
* 切片目标文件夹
* @param destWidth
* 目标切片宽度。默认200
* @param destHeight
* 目标切片高度。默认150
*/
public static void cut(String srcImageFile, String descDir,
int destWidth, int destHeight) {
try {
if (destWidth <= 0)
destWidth = 200; // 切片宽度
if (destHeight <= 0)
destHeight = 150; // 切片高度
// 读取源图像
BufferedImage bi = ImageIO.read(new File(srcImageFile));
int srcWidth = bi.getHeight(); // 源图宽度
int srcHeight = bi.getWidth(); // 源图高度
if (srcWidth > destWidth && srcHeight > destHeight) {
Image img;
ImageFilter cropFilter;
Image image = bi.getScaledInstance(srcWidth, srcHeight,
Image.SCALE_DEFAULT);
int cols = 0; // 切片横向数量
int rows = 0; // 切片纵向数量
// 计算切片的横向和纵向数量
if (srcWidth % destWidth == 0) {
cols = srcWidth / destWidth;
} else {
cols = srcWidth / destWidth + 1;
}
if (srcHeight % destHeight == 0) {
rows = srcHeight / destHeight;
} else {
rows = srcHeight / destHeight + 1;
}
// 循环建立切片，改进的想法:是否可用多线程加快切割速度
for (int i = 0; i < rows; i++) {
for (int j = 0; j < cols; j++) {
// 四个参数分别为图像起点坐标和宽高，即: CropImageFilter(int x,int y,int width,int height)
cropFilter = new CropImageFilter(j * destWidth, i
* destHeight, destWidth, destHeight);
img = Toolkit.getDefaultToolkit().createImage(
new FilteredImageSource(image.getSource(),
cropFilter));
BufferedImage tag = new BufferedImage(destWidth,
destHeight, BufferedImage.TYPE_INT_RGB);
Graphics g = tag.getGraphics();
g.drawImage(img, 0, 0, null); // 绘制缩小后的图
g.dispose();
// 输出为文件
ImageIO.write(tag, "JPEG", new File(descDir + "_r" + i
+ "_c" + j + ".jpg"));
}
}
}
} catch (Exception e) {
log.error("图片操作失败", e);
}
}
/**
* 图像类型转换：GIF->JPG、GIF->PNG、PNG->JPG、PNG->GIF(X)、BMP->PNG
*
* @param srcImageFile
* 源图像地址
* @param formatName
* 包含格式非正式名称的 String：如JPG、JPEG、GIF等
* @param destImageFile
* 目标图像地址
*/
public static void convert(String srcImageFile, String formatName,
String destImageFile) {
try {
File f = new File(srcImageFile);
f.canRead();
f.canWrite();
BufferedImage src = ImageIO.read(f);
ImageIO.write(src, formatName, new File(destImageFile));
} catch (Exception e) {
log.error("图片操作失败", e);
}
}
/**
* 彩色转为黑白
*
* @param srcImageFile
* 源图像地址
* @param destImageFile
* 目标图像地址
*/
public static void gray(String srcImageFile, String destImageFile) {
try {
BufferedImage src = ImageIO.read(new File(srcImageFile));
ColorSpace cs = ColorSpace.getInstance(ColorSpace.CS_GRAY);
ColorConvertOp op = new ColorConvertOp(cs, null);
src = op.filter(src, null);
ImageIO.write(src, "JPEG", new File(destImageFile));
} catch (IOException e) {
log.error("图片操作失败", e);
}
}
/**
* 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, IMAGE_TYPE_JPG, file);
} catch (Exception e) {
log.error("图片操作失败", e);
}
}
/**
* 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 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, IMAGE_TYPE_JPG, file);
} catch (IOException e) {
log.error("图片操作失败", e);
}
}
/**
* 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;
}
}
