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/**     * 对图片进行旋转     *     * @param src   被旋转图片     * @param angel 旋转角度     * @return 旋转后的图片     */    public static BufferedImage Rotate(Image src, int angel) {           int src_width = src.getWidth(null);        int src_height = src.getHeight(null);        // 旋转后图片        Rectangle rect_des = CalcRotatedSize(new Rectangle(new Dimension(                src_width, src_height)), angel);        BufferedImage res = null;        res = new BufferedImage(rect_des.width, rect_des.height,                BufferedImage.TYPE_INT_RGB);        Graphics2D g2 = res.createGraphics();        // 转换        g2.translate((rect_des.width - src_width) / 2,                (rect_des.height - src_height) / 2);        g2.rotate(Math.toRadians(angel), src_width / 2, src_height / 2);        g2.drawImage(src, null, null);        return res;    }    /**     * 旋转后的图片     *     * @param src   被旋转的图片     * @param angel 旋转角度     * @return 旋转后的图片     */    public static Rectangle CalcRotatedSize(Rectangle src, int angel) {           // 如果旋转的角度大于90度做相应的转换        if (angel >= 90) {               if (angel / 90 % 2 == 1) {                   int temp = src.height;                src.height = src.width;                src.width = temp;            }            angel = angel % 90;        }        double r = Math.sqrt(src.height * src.height + src.width * src.width) / 2;        double len = 2 * Math.sin(Math.toRadians(angel) / 2) * r;        double angel_alpha = (Math.PI - Math.toRadians(angel)) / 2;        double angel_dalta_width = Math.atan((double) src.height / src.width);        double angel_dalta_height = Math.atan((double) src.width / src.height);        int len_dalta_width = (int) (len * Math.cos(Math.PI - angel_alpha                - angel_dalta_width));        int len_dalta_height = (int) (len * Math.cos(Math.PI - angel_alpha                - angel_dalta_height));        int des_width = src.width + len_dalta_width * 2;        int des_height = src.height + len_dalta_height * 2;        return new Rectangle(new Dimension(des_width, des_height));    }

使用

@Override    public byte[] testImgRotate(MultipartFile face) throws Exception {           byte[] IdCartFace;        if (face.getSize() > 300000) {   //压缩            IdCartFace = ImageUtils.imageSet(face.getBytes());        } else {               IdCartFace = face.getBytes();        }        String imgFace = Base64.encode(IdCartFace).trim();//图片加密        /**         * 图片人脸角度识别+旋转处理         */        int angel = faceDetect(imgFace);//返回旋转角度值 270 180 90        BufferedImage src = ImageIO.read(face.getInputStream());        //TODO 区间旋转        //顺时针旋转xx度        BufferedImage des1 = RotateImage.Rotate(src, angel);		//int mn = (int) (Math.random() * (100 - 2) + 2);        //ImageIO.write(des1, "jpg", new File("E:\\proj\\imagexz\\" + mn + ".jpg"));        //转byte        ByteArrayOutputStream out = new ByteArrayOutputStream();        //转换编码格式JPEG        ImageIO.write(des1, "jpeg", out);        byte[] re = out.toByteArray();        return re;    }