c++ 希望以二值化操作对图片灰度进行调整

#include<iostream>
#include<fstream>
using namespace std;
int main()
{
    float** x=NULL;
    x = new float* [1024];
    for (int i = 0; i < 1024; i++)
    {
        x[i] = new float[1024];
    }
    fstream infile;
    infile.open("d:\\shepp_loggan.dat", ios::in | ios::binary);
    for (int i = 0; i < 1024; i++)
    {
        for (int j = 0; j < 1024; j++)
            infile >> x[i][j];

    }infile.close();

    for (int i = 0; i < 1024; i++)
    {
        for (int j = 0; j < 1024; j++)
        {
            cout << x[i][j] << endl;
        }
    }
    for (int i = 0; i < 1024; i++)
    {
        for (int j = 0; j < 1024; j++)
        {
            if (x[i][j] < 0.015)
                x[i][j] = 0;
            else if (x[i][j] > 0.015)
                x[i][j] = 1;
        }
    }
        fstream onfile;
        onfile.open("d:\\qwe.dat", ios::out | ios::binary);
        for (int i = 0; i < 1024; i++)
        {
            for (int j = 0; j < 1024; j++)
                onfile << x[i][j];

        }onfile.close();

        for (int i = 0; i < 1024; i++)
        {
            delete[]x[i];
        }
            delete[]x;
    
    int i = 1;
    cout << i;
    return 0;
}
![img](https://img-mid.csdnimg.cn/release/static/image/mid/ask/14344680293617.png "#left")

######输出时会重复出现负数，设定阈值后也无法对原图片进行修改。希望大佬可以不吝赐教！！！

我想要达到的结果