java圖片滑動(dòng)驗(yàn)證（登錄驗(yàn)證）原理與實(shí)現(xiàn)方法詳解

static int targetLength=55;//小圖長
static int targetWidth=45;//小圖寬
static int circleR=6;//半徑
static int r1=3;//距離點(diǎn)
/**
 * 
* @Createdate: 2019年1月24日上午10:52:42
* @Title: getBlockData
* @Description: 生成小圖輪廓
* @author mzl
* @return int[][]
* @throws
 */
private static int[][] getBlockData() {
    int[][] data = new int[targetLength][targetWidth];
    double x2 = targetLength-circleR;
    //隨機(jī)生成圓的位置
    double h2 = circleR + Math.random() * (targetWidth-3*circleR-r1);
    double po = circleR*circleR;
    double xbegin = targetLength-circleR-r1;
    double ybegin = targetWidth-circleR-r1;
    for (int i = 0; i < targetLength; i++) {
        for (int j = 0; j < targetWidth; j++) {
            double d3 = Math.pow(i - x2,2) + Math.pow(j - h2,2);
            double d2 = Math.pow(j-2,2) + Math.pow(i - h2,2);
            if ((j <= ybegin && d2 <= po)||(i >= xbegin && d3 >= po)) {
                data[i][j] = 0;
            } else {
                data[i][j] = 1;
            }
        }
    }
    return data;
}

/**
 * 
* @Createdate: 2019年1月24日上午10:51:30
* @Title: cutByTemplate
* @Description: 生成小圖片、給大圖片添加陰影
* @author mzl
* @param oriImage
* @param targetImage
* @param templateImage
* @param x
* @param y void
* @throws
 */
private static void cutByTemplate(BufferedImage oriImage,BufferedImage targetImage, int[][] templateImage, int x,int y){
    for (int i = 0; i < targetLength; i++) {
        for (int j = 0; j < targetWidth; j++) {
            int rgb = templateImage[i][j];
            // 原圖中對(duì)應(yīng)位置變色處理
            int rgb_ori = oriImage.getRGB(x + i, y + j);
            if (rgb == 1) {
      //摳圖上復(fù)制對(duì)應(yīng)顏色值
                targetImage.setRGB(i, j, rgb_ori);
      //原圖對(duì)應(yīng)位置顏色變化
                oriImage.setRGB(x + i, y + j, rgb_ori & 0x363636 );
            }else{
                //這里把背景設(shè)為透明
                targetImage.setRGB(i, j, rgb_ori & 0x00ffffff);
            }
        }
    }
}

/**
 * 
* @Createdate: 2019年1月24日上午11:49:42
* @Title: createImage
* @Description: 獲取大圖，小圖Base64碼
* @author mzl
* @param url
* @return Map<String,String>
* @throws
 */
public static Map<String,String> createImage(String url,int L,int W,Map<String,String> resultMap){
     try {
         BufferedImage bufferedImage = ImageIO.read(new FileInputStream(url));
         BufferedImage target= new BufferedImage(targetLength, targetWidth, BufferedImage.TYPE_4BYTE_ABGR);
         cutByTemplate(bufferedImage,target,getBlockData(),L,W);
         resultMap.put("b", getImageBASE64(bufferedImage));//大圖
         resultMap.put("s", getImageBASE64(target));//小圖
    } catch (IOException e) {
        e.printStackTrace();
    }finally{
        return resultMap;
    }
}
/**
* 
* @Createdate: 2019年1月24日上午11:14:19
* @Title: getImageStr
* @Description: 圖片轉(zhuǎn)BASE64
* @author mzl
* @param image
* @return
* @throws IOException String
* @throws
*/
public static String getImageBASE64(BufferedImage image) throws IOException {
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        ImageIO.write(image,"png",out);
        byte[] b = out.toByteArray();//轉(zhuǎn)成byte數(shù)組
    BASE64Encoder encoder = new BASE64Encoder();
    return encoder.encode(b);//生成base64編碼 
}