做了一个简单的去水印功能，基于文字检测去图片水印。效果如下：

插件功能代码参考如下：

using namespace cv::dnn;
TextDetectionModel_DB *textDetector=0;
void getTextDetector()
{
     if(textDetector)return;
     String modelPath = "text_detection_DB_TD500_resnet18_2021sep.onnx";  //模型权重文件

    textDetector=new TextDetectionModel_DB(modelPath);

    float binThresh = 0.3;                                      //二值图的置信度阈值
    float polyThresh  = 0.5 ;                                   //文本多边形阈值
    double unclipRatio = 2.0;      //检测到的文本区域的未压缩比率，gai比率确定输出大小
    uint maxCandidates = 200;

    textDetector->setBinaryThreshold(binThresh)
        .setPolygonThreshold(polyThresh)
        .setUnclipRatio(unclipRatio)
        .setMaxCandidates(maxCandidates);

    double scale = 1.0 / 255.0;
    int height = 736;                                                   //输出图片长宽
    int width = 736;
    Size inputSize = Size(width, height);
    Scalar mean = Scalar(122.67891434, 116.66876762, 104.00698793);
    textDetector->setInputParams(scale, inputSize, mean);

}


void deWaterMarkTextDetection(Mat &input,Mat &output,Mat &src,string)
{
    getTextDetector();
    // 推理
    std::vector<std::vector<Point>> results;
    textDetector->detect(input, results);

    Mat mask = Mat::zeros(input.size(), CV_8U);
    fillPoly(mask, results,Scalar::all(255));


    //将掩模进行膨胀，使其能够覆盖图像更大区域
    Mat kernel = getStructuringElement(MORPH_RECT, Size(5, 5));
    dilate(mask, mask, kernel);

    //使用inpaint进行图像修复
    Mat result;
    inpaint(src, mask, output, 1, INPAINT_NS);
}