cv::getTextSize 没有做参数判断段错误

[1658988725]

代码如下：会出现段错误

cv::Size textSize = cv::getTextSize(classString, cv::FONT_HERSHEY_DUPLEX, 1, 2, 0); // 2: thickness

查看接口代码,发现没有对_base_line进行参数判断

{
    const int fontpixelsize = (fontFace == 1 ? 8 : (fontFace == 5 ? 12 : 20)) * fontScale;

    int w;
    int h;
    get_text_drawing_size(text.c_str(), fontpixelsize, &w, &h);

    *_base_line = 0;

    return Size(w, h);
#if 0
    Size size;
    double view_x = 0;
    const char **faces = cv::g_HersheyGlyphs;
    const int* ascii = getFontData(fontFace);

    int base_line = (ascii[0] & 15);
    int cap_line = (ascii[0] >> 4) & 15;
    size.height = cvRound((cap_line + base_line)*fontScale + (thickness+1)/2);

    for( int i = 0; i < (int)text.size(); i++ )
    {
        int c = (uchar)text[i];
        Point p;

        readCheck(c, i, text, fontFace);

        const char* ptr = faces[ascii[(c-' ')+1]];
        p.x = (uchar)ptr[0] - 'R';
        p.y = (uchar)ptr[1] - 'R';
        view_x += (p.y - p.x)*fontScale;
    }

    size.width = cvRound(view_x + thickness);
    if( _base_line )
        *_base_line = cvRound(base_line*fontScale + thickness*0.5);
    return size;
#endif
}

应该修改为

{
    const int fontpixelsize = (fontFace == 1 ? 8 : (fontFace == 5 ? 12 : 20)) * fontScale;

    int w;
    int h;
    get_text_drawing_size(text.c_str(), fontpixelsize, &w, &h);

    if( _base_line )
        *_base_line = 0;

    return Size(w, h);
#if 0
    Size size;
    double view_x = 0;
    const char **faces = cv::g_HersheyGlyphs;
    const int* ascii = getFontData(fontFace);

    int base_line = (ascii[0] & 15);
    int cap_line = (ascii[0] >> 4) & 15;
    size.height = cvRound((cap_line + base_line)*fontScale + (thickness+1)/2);

    for( int i = 0; i < (int)text.size(); i++ )
    {
        int c = (uchar)text[i];
        Point p;

        readCheck(c, i, text, fontFace);

        const char* ptr = faces[ascii[(c-' ')+1]];
        p.x = (uchar)ptr[0] - 'R';
        p.y = (uchar)ptr[1] - 'R';
        view_x += (p.y - p.x)*fontScale;
    }

    size.width = cvRound(view_x + thickness);
    if( _base_line )
        *_base_line = cvRound(base_line*fontScale + thickness*0.5);
    return size;
#endif
}```


**正确用法应该是：**
 int baseline = 0;
cv::Size textSize = cv::getTextSize(classString, cv::FONT_HERSHEY_DUPLEX, 1, 2,&baseline); // 2: thickness

[nihui]

#146