ImageUtil图片工具: 压缩/格式转换等
发布时间：2020-12-14 03:45:27 所属栏目：大数据 来源：网络整理
导读：import net.coobird.thumbnailator.Thumbnails; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import sun.misc.BASE64Encoder; import javax.imageio.ImageIO; import java.awt.*; import java.awt.image.BufferedImage; import java.io.File;
import net.coobird.thumbnailator.Thumbnails; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import sun.misc.BASE64Encoder; import javax.imageio.ImageIO; import java.awt.*; import java.awt.image.BufferedImage; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; /** * Created by niewj on 2018/9/10. */ public class ImgUtil {// @TODO private static Logger logger = LoggerFactory.getLogger(ImgUtil.class); public static final String JPG = "jpg"; public static final String GIF = "gif"; public static final String PNG = "png"; public static final String BMP = "bmp"; public static final int K = 1024; public static final String TYPE_UNKNOWN = "unknown"; /** * png格式图片转为jpg格式 * * @param pngFile * @return */ public static File convert2Jpg(File pngFile) { // #0. 判空 if (pngFile == null || !pngFile.exists() || !pngFile.isFile() || !pngFile.canRead()) { return null; } File jpgFile = null; BufferedImage image; try { //#1. read image file image = ImageIO.read(pngFile); String parentPath = pngFile.getParent(); logger.info(ImgUtil.getPicType(new FileInputStream(pngFile))); // #2. create a blank,RGB,same width and height,and a white background BufferedImage newBufferedImage = new BufferedImage(image.getWidth(),image.getHeight(),BufferedImage.TYPE_INT_RGB); newBufferedImage.createGraphics().drawImage(image,Color.WHITE,null); // #3. create image filename long currentMillis = System.currentTimeMillis(); jpgFile = new File(parentPath,currentMillis + ".jpg"); // write to jpeg file ImageIO.write(newBufferedImage,"jpg",jpgFile); logger.info("Done"); } catch (IOException e) { e.printStackTrace(); } return jpgFile; } /** * 旋转图片 * * @param sourceFile 原图片 * @param degrees 旋转度数 * @throws IOException */ public static void rotate(File sourceFile,double degrees) throws IOException { Thumbnails.of(sourceFile) .rotate(degrees)//旋转度数 .scale(1)//缩放比例 .toFile(sourceFile); } /** * 根据文件流判断图片类型 * * @param fis * @return jpg/png/gif/bmp */ public static String getPicType(FileInputStream fis) { //读取文件的前几个字节来判断图片格式 byte[] b = new byte[4]; try { fis.read(b,b.length); String type = bytesToHexString(b).toUpperCase(); if (type.contains("FFD8FF")) { return JPG; } else if (type.contains("89504E47")) { return PNG; } else if (type.contains("47494638")) { return GIF; } else if (type.contains("424D")) { return BMP; } else { return TYPE_UNKNOWN; } } catch (IOException e) { e.printStackTrace(); } finally { if (fis != null) { try { fis.close(); } catch (IOException e) { e.printStackTrace(); } } } return null; } /** * byte数组转换成16进制字符串 * * @param src * @return */ private static String bytesToHexString(byte[] src) { StringBuilder sBuilder = new StringBuilder(); if (src == null || src.length <= 0) { return null; } for (int i = 0; i < src.length; i++) { int v = src[i] & 0xFF; String hv = Integer.toHexString(v); if (hv.length() < 2) { sBuilder.append(0); } sBuilder.append(hv); } return sBuilder.toString(); } /** * @param srcFile 待压缩的源文件 * @param desFileSize 限制的文件大小，单位Kb * @param scale 压缩比例(0,1.0] */ public static void commpressPicForScale(File srcFile,long desFileSize,double scale) { try { // #0. 获取文件类型，根据内容而不是后缀名 String type = getPicType(new FileInputStream(srcFile)); // #1. 判空 if (srcFile == null || !srcFile.exists() || !srcFile.isFile()) { return; } // #2.输出大小 long len = srcFile.length(); logger.info("源图片：" + srcFile.getAbsolutePath() + "，大小：" + len / K + "kb"); // #3. 递归方法压缩 compressImage(type,srcFile,desFileSize,scale); } catch (IOException e) { e.printStackTrace(); } } /** * 根据照片类型、精确度,上限大小，压缩指定照片 * * @param type 照片类型：jpg/png (1. type是根据文件的内容定的，而不是名字后缀值； 2. 除了jpg，其他都按照png处理) * @param srcFile 源文件和目标文件：用的同一个 * @param desFileSize 目标值限制大小，单位Kb * @param scale 压缩比：(0,1.0] */ private static void compressImage(String type,File srcFile,double scale) { if (srcFile == null || !srcFile.exists() || !srcFile.isFile()) { logger.error("_n_待压缩源文件不合要求：srcFile={}",srcFile); return; } try { long fileSize = srcFile.length(); // 1、判断大小，如果小于500kb，不压缩；如果大于等于500kb，压缩:递归结束条件 if (fileSize <= desFileSize * K) { return; } // 2. jpg格式有不失真的压缩方式；png的没有； if (JPG.equalsIgnoreCase(type)) { logger.info("jpg_file_compress:{}",srcFile.getAbsoluteFile()); Thumbnails.of(srcFile).scale(1.0f).outputQuality(scale).toFile(srcFile); } else { // 其他图片类型，一律按照PNG格式缩放 logger.info("png_file_compress:{}",srcFile.getAbsoluteFile()); Thumbnails.of(srcFile).scale(scale).toFile(srcFile); } // 3. 记录下压缩后的大小 logger.info("compressing...{}kb",srcFile.length() / K); // 4. 递归调用，直到大小符合要求 compressImage(type,scale); } catch (IOException e) { e.printStackTrace(); } } /** * 获取base64字符串 * * @param file * @return */ public static String getImageBase64(File file) { FileInputStream inputFile = null; byte[] buffer = new byte[0]; try { // #1. Base64输入流 inputFile = new FileInputStream(file); buffer = new byte[(int) file.length()]; inputFile.read(buffer); inputFile.close(); } catch (IOException e) { e.printStackTrace(); } finally { // 用完后删除文件 deleteUploadedFile(file); } return new BASE64Encoder().encode(buffer); } /** * 返回之前，把生成的文件删除掉 * * @param file */ public static void deleteUploadedFile(File file) { // 上传完文件之后，照片或视频文件删除掉 if (file != null && file.exists()) { logger.info("file deleting: ",file.getAbsolutePath()); file.delete(); } } // private static String getImageBase64(String imageId) { // File orgFile = FtpHelper.getFile(imageId); // File file = renameFile(orgFile); // ImageUtil.commpressPicForScale(file,500,0.9d); // 压缩照片 // Assert.assertion(file != null,ResponseCodeEnum.INTERNAL_HANDLE_ERROR,"file is not exit"); // FileInputStream inputFile = null; // byte[] buffer = new byte[0]; // try { // inputFile = new FileInputStream(file); // buffer = new byte[(int) file.length()]; // inputFile.read(buffer); // inputFile.close(); // } catch (Exception e) { // LOGGER.error("Exception->n {}",e); // throw new ThirdPartException(ResponseCodeEnum.INTERNAL_HANDLE_ERROR,StringMsg.fmtMsg("*")); // } finally { // 用完后删除文件 // FtpHelper.deleteUploadedFile(file); // FtpHelper.deleteUploadedFile(orgFile); // } // return new BASE64Encoder().encode(buffer); // } public static void main(String[] args) throws FileNotFoundException { // File f2 = new File("E:chrome_download1.png"); // String type2 = ImageUtil.getPicType(new FileInputStream(f2)); // System.out.println("type2=" + type2); //// ImageUtil.compressImage(type2,f2,0.9d); // File pngFile = new File("C:Usersweijun.nieDesktopthinkstatstest2.png"); // File jpgFile = convert2Jpg(pngFile); // System.out.println(jpgFile.getAbsolutePath()); System.out.printf("%02X",125); } }
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