这篇文章将为大家详细讲解有关如何使用Java实现图片切割功能，小编觉得挺实用的，因此分享给大家做个参考，希望大家阅读完这篇文章后可以有所收获。
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(); }}关于“如何使用Java实现图片切割功能”这篇文章就分享到这里了，希望以上内容可以对大家有一定的帮助，使各位可以学到更多知识，如果觉得文章不错，请把它分享出去让更多的人看到。
