Question

我想使用FileStorage类在OpenCV中输出YAML文件。目前，YAML输出没有正确的缩进。以下是.cpp代码。

FileStorage fs("detectionOutput.yml", FileStorage::WRITE)
Mat face_detect(Mat img, int count, cv::VideoWriter face_writer)
{
    Rect r;
    Mat detected_face;
    CascadeClassifier face_cascade;
    face_cascade.load("cascades_orig.xml");

    std::vector<Rect> faces;
    face_cascade.detectMultiScale( img, faces, 1.1, 2, 0|CV_HAAR_SCALE_IMAGE, Size(30, 30) );

    numOfValidRegion=0;
    for( int i = 0; i < faces.size(); i++ )
    {
        r.x = faces[i].x;
        r.y = faces[i].y;
        r.width = faces[i].width;
        r.height = faces[i].height;
        rectangle(img, r, Scalar( 0, 255, 255 ), +2, 4, 0 );    
    Rect large_face;



    large_face.x = faces[i].x ;
    large_face.y = faces[i].y ;
    large_face.width = faces[i].width;
        large_face.height = faces[i].height;


    detected_face = img(large_face);
        string path1 = prepare_path("output_ppm/face", count, i);

        string tmpStr2;
        stringstream ssFrameID;
        ssFrameID << curFrameNo;
        stringstream ssRegionID;
        ssRegionID << i;
        tmpStr2 = "frame"+ ssFrameID.str()+"region"+ssRegionID.str();
        fs << tmpStr2 << "";
        fs << "numPts" << 2;
        Mat tmpMat(2,2,DataType<int>::type);
    tmpMat.at<int>(0,0) = large_face.x ;  // TLx
        tmpMat.at<int>(0,1) = large_face.y ;  // TLy
        tmpMat.at<int>(1,0) = large_face.x + large_face.width  ;  // BRx
        tmpMat.at<int>(1,1) = large_face.y + large_face.height ;  // BRy
        fs << "matPts" << tmpMat;
        fs << "attribute" << "head";
        numOfValidRegion++;
    }
    string tmpStr;
    stringstream ss;
    ss << curFrameNo;
    tmpStr = "frame"+ss.str()+"numValidRegions";
    fs << tmpStr << numOfValidRegion;
    return img;
}

以下是当前的YAML输出

frame0Region0: ""
numPts: 2
matPts: !!opencv-matrix
   rows: 2
   cols: 2
   dt: i
   data: [ 1156, 336, 1206, 386 ]
attribute: head
frame0Region1: ""
numPts: 2
matPts: !!opencv-matrix
   rows: 2
   cols: 2
   dt: i
   data: [ 1112, 376, 1181, 445 ]
attribute: head
frame0Region2: ""
numPts: 2
matPts: !!opencv-matrix
   rows: 2
   cols: 2
   dt: i
   data: [ 1177, 385, 1252, 460 ]
attribute: head
frame0Region3: ""
numPts: 2
matPts: !!opencv-matrix
   rows: 2
   cols: 2
   dt: i
   data: [ 140, 310, 245, 415 ]
attribute: head
frame0numValidRegions: 4

我希望以下输出具有正确的缩进，我不希望在（frame0Region0: ""）前面加双引号，但是当我删除双引号时，它会显示错误。

frame0region0:
   numPts: 2
   matPts: !!opencv-matrix
      rows: 2
      cols: 2
      dt: i
      data: [ 1156, 336, 1206, 386 ]
   attribute: head
frame0region1:
   numPts: 2
   matPts: !!opencv-matrix
      rows: 2
      cols: 2
      dt: i
      data: [ 1112, 376, 1181, 445 ]
   attribute: head
frame0region2:
   numPts: 2
   matPts: !!opencv-matrix
      rows: 2
      cols: 2
      dt: i
      data: [ 1177, 385, 1252, 460 ]
   attribute: head
frame0region3:
   numPts: 2
   matPts: !!opencv-matrix
      rows: 2
      cols: 2
      dt: i
      data: [ 140, 310, 245, 415 ]
   attribute: head
frame0numValidRegions: 4

Answer 1

YAML从左向右阅读，因此""实际上位于frame0Region0键后面。

如果删除""，然后缩进以下值，则实际上完全改变了含义：

abc: ""
xyz: 1

定义了两个键：abc，其值为空字符串标量，xyz，其值为整数。鉴于：

abc: 
  xyz: 1

由于缩进，将键abc的值定义为映射，其第一个键是xyz。这有一个完全不同的结构，不会加载。

即使你不会缩进，但只是删除""，你会将空标量字符串更改为空标量（在C ++中作为NULL指针加载），这不太可能被处理所接受没有明确测试的软件。

YAML缩进OpenCV

1 个答案: