Serializing OpenCV Mat_

Question

I\'m working on a robotics research project where I need to serialize 2D matrices of 3D points: basically each pixel is a 3-vector of floats. These pixels are saved in an Op

Answer 1

I wrote this code:

/*
Will save in the file:
cols\n
rows\n
elemSize\n
type\n
DATA
*/
void serializeMatbin(Mat& mat, std::string filename){
    if (!mat.isContinuous()) {
        cout << "Not implemented yet" << endl;
        exit(1);
    }
    int elemSizeInBytes = (int)mat.elemSize();
    int elemType        = (int)mat.type();
    int dataSize        = (int)(mat.cols * mat.rows * mat.elemSize());

    FILE* FP = fopen(filename.c_str(), "wb");
    int sizeImg[4] = {mat.cols, mat.rows, elemSizeInBytes, elemType };
    fwrite(/*buffer*/ sizeImg, /*howmanyelements*/ 4, /* size of each element */ sizeof(int), /*file*/ FP);
    fwrite(mat.data, mat.cols * mat.rows, elemSizeInBytes, FP);
    fclose(FP);
}

Mat deserializeMatbin(std::string filename){
    FILE* fp = fopen(filename.c_str(), "r");
    int header[4];
    fread(header, sizeof(int), 4, fp);
    int cols = header[0]; 
    int rows = header[1];
    int elemSizeInBytes = header[2];
    int elemType = header[3];

    Mat outputMat = Mat(rows, cols, elemType);

    fread(outputMat.data, elemSizeInBytes, cols * rows, fp);
    fclose(fp);
    return outputMat;
}

void testSerializeMatbin(){
    Mat a = Mat::ones(/*cols*/ 10, /* rows */ 5, CV_8U) * 2;
    std::string filename = "test.matbin";
    serializeMatbin(a, filename);
    Mat b = deserializeMatbin(filename);
    cout << "Rows: " << b.rows << " Cols: " << b.cols << " type: " << b.type()<< endl;
}