本文实例为大家分享了Java实现图片切割功能的具体代码，供大家参考，具体内容如下
工具类
package com.xudaolong.Utils;
import javax.imageio.IIOImage;
import javax.imageio.ImageIO;
import javax.imageio.ImageReader;
import javax.imageio.ImageWriter;
import javax.imageio.stream.ImageInputStream;
import javax.imageio.stream.ImageOutputStream;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.Arrays;
import java.util.Iterator;
public class ImageCutterUtil {
public enum IMAGE_FORMAT {
BMP("bmp"),
JPG("jpg"),
WBMP("wbmp"),
JPEG("jpeg"),
PNG("png"),
GIF("gif");
private String value;
IMAGE_FORMAT(String value) {
this.value = value;
}
public String getValue() {
return value;
}
public void setValue(String value) {
this.value = value;
}
}
public static String getImageFormatName(File file) throws IOException {
String formatName = null;
ImageInputStream iis = ImageIO.createImageInputStream(file);
Iterator<ImageReader> imageReader = ImageIO.getImageReaders(iis);
if (imageReader.hasNext()) {
ImageReader reader = imageReader.next();
formatName = reader.getFormatName();
}
return formatName;
}
public static BufferedImage[] readerImage(File file) throws IOException {
BufferedImage sourceImage = ImageIO.read(file);
BufferedImage[] images = null;
ImageInputStream iis = ImageIO.createImageInputStream(file);
Iterator<ImageReader> imageReaders = ImageIO.getImageReaders(iis);
if (imageReaders.hasNext()) {
ImageReader reader = imageReaders.next();
reader.setInput(iis);
int imageNumber = reader.getNumImages(true);
images = new BufferedImage[imageNumber];
for (int i = 0; i < imageNumber; i++) {
BufferedImage image = reader.read(i);
if (sourceImage.getWidth() > image.getWidth() || sourceImage.getHeight() > image.getHeight()) {
image = zoom(image, sourceImage.getWidth(), sourceImage.getHeight());
}
images[i] = image;
}
reader.dispose();
iis.close();
}
return images;
}
public static BufferedImage[] processImage(BufferedImage[] images, int x, int y, int width, int height) throws Exception {
if (null == images) {
return images;
}
BufferedImage[] oldImages = images;
images = new BufferedImage[images.length];
for (int i = 0; i < oldImages.length; i++) {
BufferedImage image = oldImages[i];
images[i] = image.getSubimage(x, y, width, height);
}
return images;
}
public static void writerImage(BufferedImage[] images, String formatName, File file) throws Exception {
Iterator<ImageWriter> imageWriters = ImageIO.getImageWritersByFormatName(formatName);
if (imageWriters.hasNext()) {
ImageWriter writer = imageWriters.next();
String fileName = file.getName();
int index = fileName.lastIndexOf(".");
if (index > 0) {
fileName = fileName.substring(0, index + 1) + formatName;
}
String pathPrefix = getFilePrefixPath(file.getPath());
File outFile = new File(pathPrefix + fileName);
ImageOutputStream ios = ImageIO.createImageOutputStream(outFile);
writer.setOutput(ios);
if (writer.canWriteSequence()) {
writer.prepareWriteSequence(null);
for (int i = 0; i < images.length; i++) {
BufferedImage childImage = images[i];
IIOImage image = new IIOImage(childImage, null, null);
writer.writeToSequence(image, null);
}
writer.endWriteSequence();
} else {
for (int i = 0; i < images.length; i++) {
writer.write(images[i]);
}
}
writer.dispose();
ios.close();
}
}
public static void cutImage(File sourceFile, File destFile, int x, int y, int width, int height) throws Exception {
// 读取图片信息
BufferedImage[] images = readerImage(sourceFile);
// 处理图片
images = processImage(images, x, y, width, height);
// 获取文件后缀
String formatName = getImageFormatName(sourceFile);
destFile = new File(getPathWithoutSuffix(destFile.getPath()) + formatName);
// 写入处理后的图片到文件
writerImage(images, formatName, destFile);
}
public static void getOSSupportsStandardImageFormat() {
String[] readerFormatName = ImageIO.getReaderFormatNames();
String[] readerSuffixName = ImageIO.getReaderFileSuffixes();
String[] readerMIMEType = ImageIO.getReaderMIMETypes();
System.out.println("========================= OS supports reader ========================");
System.out.println("OS supports reader format name : " + Arrays.asList(readerFormatName));
System.out.println("OS supports reader suffix name : " + Arrays.asList(readerSuffixName));
System.out.println("OS supports reader MIME type : " + Arrays.asList(readerMIMEType));
String[] writerFormatName = ImageIO.getWriterFormatNames();
String[] writerSuffixName = ImageIO.getWriterFileSuffixes();
String[] writerMIMEType = ImageIO.getWriterMIMETypes();
System.out.println("========================= OS supports writer ========================");
System.out.println("OS supports writer format name : " + Arrays.asList(writerFormatName));
System.out.println("OS supports writer suffix name : " + Arrays.asList(writerSuffixName));
System.out.println("OS supports writer MIME type : " + Arrays.asList(writerMIMEType));
}
private static BufferedImage zoom(BufferedImage sourceImage, int width, int height) {
BufferedImage zoomImage = new BufferedImage(width, height, sourceImage.getType());
Image image = sourceImage.getScaledInstance(width, height, Image.SCALE_SMOOTH);
Graphics gc = zoomImage.getGraphics();
gc.setColor(Color.WHITE);
gc.drawImage(image, 0, 0, null);
return zoomImage;
}
public static String getFilePrefixPath(File file) throws IOException {
String path = null;
if (!file.exists()) {
throw new IOException("not found the file !");
}
String fileName = file.getName();
path = file.getPath().replace(fileName, "");
return path;
}
public static String getFilePrefixPath(String path) throws Exception {
if (null == path || path.isEmpty()) throw new Exception("文件路径为空！");
int index = path.lastIndexOf(File.separator);
if (index > 0) {
path = path.substring(0, index + 1);
}
return path;
}
public static String getPathWithoutSuffix(String src) {
String path = src;
int index = path.lastIndexOf(".");
if (index > 0) {
path = path.substring(0, index + 1);
}
return path;
}
public static String getFileName(String filePath) throws IOException {
File file = new File(filePath);
if (!file.exists()) {
throw new IOException("not found the file !");
}
return file.getName();
}
public static void main(String[] args) throws Exception {
// 获取系统支持的图片格式
// ImageCutterUtil.getOSSupportsStandardImageFormat();
try {
// 起始坐标，剪切大小
int x = 14;
int y = 24;
int width = 62;
int height = 62;
// 参考图像大小
int clientWidth = 88;
int clientHeight = 88;
File file = new File("/Users/mac/IdeaProjects/QRdemo/resources/src/com/xudaolong/QR/TestQR/QR.jpg");
BufferedImage image = ImageIO.read(file);
double destWidth = image.getWidth();
double destHeight = image.getHeight();
if (destWidth < width || destHeight < height)
throw new Exception("源图大小小于截取图片大小!");
double widthRatio = destWidth / clientWidth;
double heightRatio = destHeight / clientHeight;
x = Double.valueOf(x * widthRatio).intValue();
y = Double.valueOf(y * heightRatio).intValue();
width = Double.valueOf(width * widthRatio).intValue();
height = Double.valueOf(height * heightRatio).intValue();
System.out.println("裁剪大小 x:" + x + ",y:" + y + ",width:" + width + ",height:" + height);
String formatName = getImageFormatName(file);
String pathSuffix = "." + formatName;
String pathPrefix = getFilePrefixPath(file);
String targetPath = pathPrefix + System.currentTimeMillis() + pathSuffix;
File destFile = new File(targetPath);
ImageCutterUtil.cutImage(file, destFile, x, y, width, height);
} catch (IOException e) {
e.printStackTrace();
}
}
}单方面测试
public void cutQR(String sourcePath) {
try {
File file = new File(sourcePath);
BufferedImage image = ImageIO.read(file);
// 起始坐标，剪切大小
int x = 14;
int y = 25;
int width = 62;
int height = 62;
// 参考图像大小
int clientWidth = 88;
int clientHeight = 88;
double destWidth = image.getWidth();
double destHeight = image.getHeight();
if (destWidth < width || destHeight < height)
throw new Exception("源图大小小于截取图片大小!");
double widthRatio = destWidth / clientWidth;
double heightRatio = destHeight / clientHeight;
//修改一下单位
x = Double.valueOf(x * widthRatio).intValue();
y = Double.valueOf(y * heightRatio).intValue();
width = Double.valueOf(width * widthRatio).intValue();
height = Double.valueOf(height * heightRatio).intValue();
System.out.println("裁剪大小 x:" + x + ",y:" + y + ",width:" + width + ",height:" + height);
//获取指定的名字
// String formatName = getImageFormatName(file);
// String pathSuffix = "." + formatName;
// String pathPrefix = getFilePrefixPath(file);
// String targetPath = pathPrefix + System.currentTimeMillis() + pathSuffix;
//最后一步进行裁剪到指定的名字
File destFile = new File(sourcePath);
ImageCutterUtil.cutImage(file, destFile, x, y, width, height);
} catch (Exception e) {
e.printStackTrace();
}
}以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持编程网。
