2019-12-10 java 图片压缩

 public static void jpgCompress(String filePath) {

       String filePath= "需要压缩的图片路径";
       File file = new File(filePath);
       float qality = (float)0.4;
       try {
           compressPictureByQality(file,qality);
       } catch (IOException e) {
           e.printStackTrace();
       }

    }

 /**
     * 压缩图片
     *
     * @param file
     * @param qality 参数qality是取值0~1范围内  代表压缩的程度
     * @return
     * @throws IOException
     */
    public static File compressPictureByQality(File file, float qality) throws IOException {
        BufferedImage src = null;
        FileOutputStream out = null;
        ImageWriter imgWrier;
        ImageWriteParam imgWriteParams;
        System.out.println("开始设定压缩图片参数");
        // 指定写图片的方式为 jpg
        imgWrier = ImageIO.getImageWritersByFormatName("png").next();
        imgWriteParams = new javax.imageio.plugins.jpeg.JPEGImageWriteParam(null);
        // 要使用压缩，必须指定压缩方式为MODE_EXPLICIT
        imgWriteParams.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);
        // 这里指定压缩的程度，参数qality是取值0~1范围内，
        imgWriteParams.setCompressionQuality(qality);
        imgWriteParams.setProgressiveMode(ImageWriteParam.MODE_DISABLED);
        // ColorModel.getRGBdefault();
        ColorModel colorModel = ImageIO.read(file).getColorModel();
        imgWriteParams.setDestinationType(new javax.imageio.ImageTypeSpecifier(colorModel, colorModel.createCompatibleSampleModel(32, 32)));
        logger.info("结束设定压缩图片参数");
        if (!file.exists()) {
            logger.error("Not Found Img File,文件不存在");
            return null;
        } else {
            logger.info("图片转换前大小:{}", file.length() / 1024 + "kb");
            src = ImageIO.read(file);
            out = new FileOutputStream(file);
            imgWrier.reset();
            // 必须先指定 out值，才能调用write方法, ImageOutputStream可以通过任何
            // OutputStream构造
            imgWrier.setOutput(ImageIO.createImageOutputStream(out));
            // 调用write方法，就可以向输入流写图片
            imgWrier.write(null, new IIOImage(src, null, null),
                    imgWriteParams);
            out.flush();
            out.close();
            logger.info("图片转换后大小", file.length() / 1024 + "kb");
            return file;
        }
    }

以上供参！