Question

我正在使用 openCV 开发一个小型演示，该演示可以使用实时摄像头检测人体。

当前，我的应用成功检测到脸部。因此，我的问题是，如何像面部检测那样检测人体。

这是我的代码（每帧都会调用）：-

///1. Convert input UIImage to Mat
std::vector<cv::Rect> faces;
CGImageRef image = CGImageCreateCopy(source.CGImage);
CGFloat cols = CGImageGetWidth(image);
CGFloat rows = CGImageGetHeight(image);
cv::Mat frame(rows, cols, CV_8UC4);

CGBitmapInfo bitmapFlags = kCGImageAlphaNoneSkipLast | kCGBitmapByteOrderDefault;
size_t bitsPerComponent = 8;
size_t bytesPerRow = frame.step[0];
CGColorSpaceRef colorSpace = CGImageGetColorSpace(image);

CGContextRef context = CGBitmapContextCreate(frame.data, cols, rows, bitsPerComponent, bytesPerRow, colorSpace, bitmapFlags);
CGContextDrawImage(context, CGRectMake(0.0f, 0.0f, cols, rows), image);
CGContextRelease(context);
cv::Mat frame_gray;

cvtColor( frame, frame_gray, CV_BGR2GRAY );
equalizeHist( frame_gray, frame_gray );

///2. detection
NSString *eyes_cascade_name = [[NSBundle mainBundle] pathForResource:@"haarcascade_eye" ofType:@"xml"];
NSString *face_cascade_name = [[NSBundle mainBundle] pathForResource:@"haarcascade_frontalface_default" ofType:@"xml"];
if(!cascade_loaded){
    std::cout<<"loading ..";
    if( !eyes_cascade.load( std::string([eyes_cascade_name UTF8String]) ) ){ printf("--(!)Error loading\n"); return source;};
    if( !face_cascade.load( std::string([face_cascade_name UTF8String]) ) ){ printf("--(!)Error loading\n"); return source;};
    cascade_loaded = true;
}
face_cascade.detectMultiScale(frame_gray, faces, 1.3, 5, CV_HAAR_SCALE_IMAGE);
for( size_t i = 0; i < faces.size(); i++ )
{
    cv::Point center( faces[i].x + faces[i].width*0.5, faces[i].y + faces[i].height*0.5 );
    ellipse( frame, center, cv::Size( faces[i].width*0.5, faces[i].height*0.5), 0, 0, 360, cv::Scalar( 0, 100, 255 ), 4, 8, 0 );

    cv::Mat faceROI = frame_gray( faces[i] );
    std::vector<cv::Rect> eyes;

    //-- In each face, detect eyes
    eyes_cascade.detectMultiScale( faceROI, eyes, 1.1, 2, 0 |CV_HAAR_SCALE_IMAGE, cv::Size(30, 30) );

    for( size_t j = 0; j < eyes.size(); j++ )
    {
        cv::Point center( faces[i].x + eyes[j].x + eyes[j].width*0.5, faces[i].y + eyes[j].y + eyes[j].height*0.5 );
        int radius = cvRound( (eyes[j].width + eyes[j].height)*0.25 );
        circle( frame, center, radius, cv::Scalar( 5, 255, 0 ), 2, 8, 0 );
    }
}

如何使用OpenCV检测人体轮廓？

0 个答案: