ios - OpenCV - 为轮廓创建边界框和圆圈 - Xcode [Objective-C++]

Question

和我类似的问题已经发布了，但是还有一些部分不适合我目前的问题。我使用 Xcode和 Objective C++ 与 openCV 一起工作。

我想做的是在照片中围绕人眼创建一些边界框和圆圈。我使用了以下代码，但这不起作用:

-(void)detectEye {

cv::Mat src_gray;
int thresh = 100;
RNG rng(12345);

NSString *path = @"/Users/NazarMedeiros/Desktop/image.jpg";

cv::Mat src = cv::imread("/Users/NazarMedeiros/Downloads/face.jpg");
if (src.empty())
    return;

cv::cvtColor(src, src_gray, CV_BGR2GRAY );
cv::blur(src_gray, src_gray, cv::Size(3,3) );

cv::Mat threshold_output;
std::vector<std::vector<cv::Point> > contours;
std::vector<Vec4i> hierarchy;

/// Detect edges using Threshold
cv::threshold( src_gray, threshold_output, thresh, 255, THRESH_BINARY );
/// Find contours
cv::findContours(threshold_output, contours, hierarchy, CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE, cv::Point(0, 0) );

/// Approximate contours to polygons + get bounding rects and circles
std::vector<std::vector<cv::Point> > contours_poly( contours.size() );
std::vector<cv::Rect> boundRect( contours.size() );
std::vector<Point2f>center( contours.size() );
std::vector<float>radius( contours.size() );

for(int i = 0; i < contours.size(); i++ ) {
    cv::approxPolyDP(cv::Mat(contours[i]), contours_poly[i], 3, true );
    boundRect[i] = cv::boundingRect(cv::Mat(contours_poly[i]) );
    cv::minEnclosingCircle( (cv::Mat)contours_poly[i], center[i], radius[i] );
}

/// Draw polygonal contour + bonding rects + circles
Mat drawing = Mat::zeros( threshold_output.size(), CV_8UC3 );
for(int i = 0; i < contours.size(); i++ ) {
    cv::Scalar color = Scalar(rng.uniform(0, 255), rng.uniform(0,255), rng.uniform(0,255) );
    cv::drawContours( drawing, contours_poly, i, color, 1, 8, std::vector<Vec4i>(), 0, cv::Point() );
    cv::circle( drawing, center[i], (int)radius[i], color, 2, 8, 0 );
}
imwrite([path UTF8String], src);}

}imwrite 函数不保存我的图像..

有人能帮帮我吗？此致，纳扎尔·梅代罗斯

Answer 1

尝试将“绘图”转换为 UIImage

- (UIImage *)UIImageFromCVMat:(cv::Mat)cvMat
{
    NSData *data = [NSData dataWithBytes:cvMat.data length:cvMat.elemSize()*cvMat.total()];
    CGColorSpaceRef colorSpace;

    if (cvMat.elemSize() == 1) {
        colorSpace = CGColorSpaceCreateDeviceGray();
    } else {
        colorSpace = CGColorSpaceCreateDeviceRGB();
    }

    CGDataProviderRef provider = CGDataProviderCreateWithCFData((__bridge CFDataRef)data);

    // Creating CGImage from cv::Mat
    CGImageRef imageRef = CGImageCreate(cvMat.cols,                                 //width
                                        cvMat.rows,                                 //height
                                        8,                                          //bits per component
                                        8 * cvMat.elemSize(),                       //bits per pixel
                                        cvMat.step[0],                            //bytesPerRow
                                        colorSpace,                                 //colorspace
                                        kCGImageAlphaNone|kCGBitmapByteOrderDefault,// bitmap info
                                        provider,                                   //CGDataProviderRef
                                        NULL,                                       //decode
                                        false,                                      //should interpolate
                                        kCGRenderingIntentDefault                   //intent
                                        );


    // Getting UIImage from CGImage
    UIImage *finalImage = [UIImage imageWithCGImage:imageRef];
    CGImageRelease(imageRef);
    CGDataProviderRelease(provider);
    CGColorSpaceRelease(colorSpace);

    return finalImage;
}