应用CLAHE和THRESHOLD时OpenCV iOS奇怪的行为

Question

我有两种方法：一种用于对CLAHE进行对比度校正，另一种用于对图像进行二值化。

我称之为的顺序是：1。CLAHE，2。Binarize

当我只使用一个时，它们都很好用。但是当我按照上面提到的顺序打电话时，我得到了这张照片：

我的CLAHE代码：

- (UIImage*)correctContrast:(UIImage*)image {

    cv::Mat cvImage = [self cvMatFromUIImage:image];

    cv::Mat grayImage;
    cv::cvtColor(cvImage, grayImage, CV_BGR2GRAY);

    cv::Mat contrastCorrectedImage;
    cv::Ptr<cv::CLAHE> clahe = cv::createCLAHE();
    clahe->setClipLimit(1.5);
    clahe->apply(grayImage, contrastCorrectedImage);

    UIImage* contrastCorrectedUIImage = [self UIImageFromCVMat:contrastCorrectedImage];

    return contrastCorrectedUIImage;
}

对图像进行二值化：

- (UIImage*)binarize:(UIImage*)image {
    cv::Mat cvImage = [self cvMatFromUIImage:image];

    cv::Mat grayImage;
    cv::cvtColor(cvImage, grayImage, CV_BGR2GRAY);

    double MAX_THRESHOLD = 255;
    double THRESHOLD_VALUE = 165;
    cv::Mat binarizedImage;
    cv::threshold(grayImage, binarizedImage, THRESHOLD_VALUE, MAX_THRESHOLD, CV_THRESH_BINARY);

    UIImage* binarizedUIImage = [self UIImageFromCVMat:binarizedImage];

    return binarizedUIImage;
}

以及我如何使用它们：

let contrastImage = self.openCV.correctContrast(uiImageCropped!)
let binarizedImage = self.openCV.binarize(contrastImage!)
self.image = binarizedImage

修改 输入图像只是一张普通的名片。