Is there a way to keep imwrite from overwriting files..?

edit

Just check if the file exists - problem solved...

I don't know if there is a function of check duplicates and save as another name in OpenCV, so I made it below.

Got checking file existance code from sturkmen above.

It is not very well coded, so modify it with your own taste.

/*
     If filename test.jpg exists, it saves same name input as 
    test(1).jpg, test(2).jpg, ...
*/
const String& imwriteSafe(const String& filename, InputArray img,
    const std::vector<int>& params = std::vector<int>()) {

    static FILE *f;
    static String newname;

    f = fopen(filename.c_str(), "rb");
    newname = filename; 

    if (f) {
        int counter = 0;
        const int extension_dot = filename.find_first_of('.');
        String name = filename.substr(0, extension_dot);
        String extension = filename.substr(extension_dot);
        do{
            ++counter;
            newname = (name + "(" + to_string(counter) + ")" + extension);
            fclose(f);
            f = fopen(newname.c_str(), "rb");
        }while(f);
    }

    if (cv::imwrite(newname, img, params))
        return newname;
    else
        throw 0;
}

// using example.
int main(){
    cv::String filename = "...."
    cv::Mat image = ....

    // some code here

    try {
        cv::String writedfilename = imwriteSafe(filename, image);
        cout<<"Writed "<<writedfilename<<endl;
    }
    catch(int e){
        cout<<"Writing "<<filename<<"failed."<<endl;
    }
}

look a sample code below. for more information you can look here

#include "opencv2/imgcodecs.hpp"
#include <iostream>

using namespace cv;

static bool isFileExist( const String& filename )
{
    /// Open the file
    FILE* f= fopen( filename.c_str(), "rb" );

    /// in the event of a failure, return false
    if( !f )
        return false;

    fclose(f);

    return true;
}


int main(int /*argc*/, char** /*argv*/)
{
    Mat test = Mat::zeros(100, 100, CV_8UC1);

    String filename = "test.jpg";

    if( !isFileExist(filename))
        imwrite(filename, test);
    else std::cout << filename  << " exist. not saved" << std::endl;

    return 0;
}