Converting bitmap data to rgb visual c++ - c++

Question

I am trying to take a bitmap image and get the RGB values of the pixels. What I currently have will open the bitmap file and read the pixel data:
#define _CRT_SECURE_NO_DEPRECATE
#include "findColor.h"
#include <vector>
#include <iostream>
int findColor(std::string path) {
std::vector<std::string> averageColor; //Will hold the average hex color of each image in order.
std::string currentImage;
currentImage = path + std::to_string(i) + ".btm";
FILE* f = fopen(currentImage.c_str(), "rb");
unsigned char info[54]; //Bitmap header is 54 bytes
fread(info, sizeof(unsigned char), 54, f); //reading the header
// extract image height and width from header
int width, height;
memcpy(&width, info + 18, sizeof(int));
memcpy(&height, info + 22, sizeof(int));
int heightSign = 1;
if (height < 0) {
heightSign = -1;
}
int size = 3 * width * height; //size of image in bytes. 3 bytes per pixel.
unsigned char* data = new unsigned char[size]; // allocate 3 bytes per pixel
fread(data, sizeof(unsigned char), size, f); // read the rest of the data at once
fclose(f); //close image.
for (i = 0; i < size; i += 3) //Flip the image data? It is stored as BGR flipping it to RGB?
{
unsigned char tmp = data[i-33];
data[i] = data[i + 2];
data[i + 2] = tmp;
}
return 0;
}
I really don't know where to go from here. Any responses will be appreciated.