Java图片批量压缩像素的实现方法

 public static void main(String[] args) throws ioException {

        String modpath = "C:\\Users\\Administrator\\Desktop\\鲲鹏认证\\test\\";

        getFiles("C:\\Users\\Administrator\\Desktop\\鲲鹏认证\\测试用例清单", modpath, 160);//将图片压缩至100宽

    }

    public static void resizeImage(String srcPath, String desPath, int width, int height) throws IOException {

        File srcFile = new File(srcPath);

        Image srcImg = ImageIO.read(srcFile);

        BufferedImage buffImg = null;

        buffImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);

        //使用TYPE_INT_RGB修改的图片会变色

        buffImg.getGraphics().drawImage(srcImg.getScaledInstance(width, height, Image.SCALE_SMOOTH), 0, 0, null);

        String filePath="";

        if (srcFile.getName().contains("#")) {

             filePath = srcFile.getName().replace("#", "");

        }else{

            filePath=srcFile.getName();

        }

        ImageIO.write(buffImg, "PNG", new File(desPath + filePath));

    }

    public static void getFiles(String path, String modPath, int scaleSize) throws IOException {

        ArrayList<String> files = new ArrayList<String>();

        File file = new File(path);

        File[] tempList = file.listFiles();

        //循环读取目录下图片

        for (int i = 0; i < tempList.length; i++) {

            String filePath = tempList[i].getName();

            if (tempList[i].isFile()) {

                System.out.println("文件：" + filePath + "-" + tempList[i].getAbsolutePath().replaceAll("\\\\", "/"));

                String[] imagePath = tempList[i].getAbsolutePath().replaceAll("\\\\", "/").split("/");

                String imageNumber = null;

                FileUtil.resizeImage(tempList[i].getAbsolutePath().replaceAll("\\\\", "/"), modPath, 160, 160);

                files.add(tempList[i].toString());

            }

            if (tempList[i].isDirectory()) {

                  System.out.println("文件夹：" + tempList[i]);

            }

        }

        System.out.println(path + "下文件数量：" + files.size());

    }

	

	public static byte[] compressImage(byte[] imageByte, int ppi) {

		byte[] smallImage = null;

		int width = 0, height = 0;

 

		if (imageByte == null)

			return null;

 

		ByteArrayInputStream byteInput = new ByteArrayInputStream(imageByte);

		try {

			Image image = ImageIO.read(byteInput);

			int w = image.getWidth(null);

			int h = image.getHeight(null);

			// adjust weight and height to avoid image distortion

			double scale = 0;

			scale = Math.min((float) ppi / w, (float) ppi / h);

			width = (int) (w * scale);

			width -= width % 4;

			height = (int) (h * scale);

 

			if (scale >= (double) 1)

				return imageByte;

 

			BufferedImage buffImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);

			buffImg.getGraphics().drawImage(image.getScaledInstance(width, height, Image.SCALE_SMOOTH), 0, 0, null);

			ByteArrayOutputStream out = new ByteArrayOutputStream();

			ImageIO.write(buffImg, "png", out);

			smallImage = out.toByteArray();

			return smallImage;

 

		} catch (IOException e) {

			log.error(e.getMessage());

			throw new RSServerInternalException("");

		}

	}

BufferedImage buffImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);

buffImg.getGraphics().drawImage(image.getScaledInstance(width, height, Image.SCALE_SMOOTH), 0, 0, null);