opencv imread() on Windows for non-ASCII file names

Question

We have an OpenCV problem of opening (and writing) file paths that contain non-Ascii characters on Windows. I saw questions OpenCV imread with foreign characters and imread

Answer 1

Try this:

cv::Mat ReadImage(const wchar_t* filename)
{
    FILE* fp = _wfopen(filename, L"rb");
    if (!fp)
    {
        return Mat::zeros(1, 1, CV_8U);
    }
    fseek(fp, 0, SEEK_END);
    long sz = ftell(fp);
    char* buf = new char[sz];
    fseek(fp, 0, SEEK_SET);
    long n = fread(buf, 1, sz, fp);
    _InputArray arr(buf, sz);
    Mat img = imdecode(arr, CV_LOAD_IMAGE_COLOR);
    delete[] buf;
    fclose(fp);
    return img;
}