Implementing I/O operations on XML and YAML files

1. Open and close the file

The data structure of the Xml\yaml file in OpenCV is Filestorage, which opens operations such as:

string " I.xml " ; Filestorage FS (filename, filestorage::write); \\...fs.open (filename, filestorage::read);

The file close operation will be done automatically when the filestorage structure is destroyed, but it can also be called the following function implementation

Fs.release ();

2. Input and output of text and numbers

Write files using the << operator, for example:

" Iterationnr " ;

Read the file, using the >> operator, for example

int itnr;fs["Iterationnr"] >>= (int) fs["  Iterationnr"];

3. The input and output of the OPENCV data structure is the same as the basic C + + form

Mat R = Mat_<uchar >::eye (3,3), T= mat_<Double>::zeros (3,1); FS<<"R"<< R;//Write Cv::matFS <<"T"<<t;fs["R"] >> R;//Read Cv::matfs["T"] >> T;

4. Input and output of vector (arrays) and maps

The vector should be careful to add "[" to the first element before the last element with "]". For example:

FS <<"Strings"<<"[";//text-string SequenceFS <<"image1.jpg"<<"awesomeness"<<"baboon.jpg"; FS<<"]";//Close Sequence

The symbols used for the operation of the map structure are "{" and "}", for example

" Mapping " // text-mapping " {""one"1"  2"}";

When reading these structures, the filenode and filenodeiterator data structures are used. The [] operator of the Filestorage class returns the Filenode data type, and for a series of node, you can use the filenodeiterator structure, for example:

5. File read

 filenode n = Fs[ " strings  " ]; //  Read string Sequence–get node  if  (N.type ()!= Filenode::seq) {cerr  <<  "  strings is not a sequence! FAIL   << Endl;  return  1  ;} Filenodeiterator It  = N.begin (), it_end = N.end (); //  Go through the node  for  (; it! = It_end; ++it) cout  << (string ) *it << Endl; 

6. Example Introduction

if(Filename.empty ()) {return 0;    } cv::filestorage FS (Filename,cv::filestorage::write); if(!fs.isopened ()) {        return 0; } FS<<"Prefiltercap"<<stBM.state->Prefiltercap; FS<<"sadwindowsize"<<stBM.state->sadwindowsize; FS<<"mindisparity"<<stBM.state->mindisparity; FS<<"numberofdisparities"<<stBM.state->numberofdisparities; FS<<"Texturethreshold"<<stBM.state->Texturethreshold; FS<<"Uniquenessratio"<<stBM.state->Uniquenessratio; FS<<"specklewindowsize"<<stBM.state->specklewindowsize; FS<<"Specklerange"<<stBM.state->Specklerange; FS<<"Leftvalidarea" ; FS<<"{"<<"roi1x"<<stBM.state->roi1.x; FS<<"roi1y"<<stBM.state->roi1.y; FS<<"Roi1width"<<stBM.state->Roi1.width; FS<<"Roi1height"<<stBM.state->Roi1.height; FS<<"}" ; FS<<"Rightvalidarea" ; FS<<"{"<<"roi2x"<<stBM.state->roi2.x; FS<<"roi2y"<<stBM.state->roi2.y; FS<<"Roi2width"<<stBM.state->Roi2.width; FS<<"Roi2height"<<stBM.state->Roi2.height; FS<<"}" ; Fs.release ();

7. Experimental results

Implementing I/O operations on XML and YAML files