helpers.c

#include "helpers.h"
#include <math.h>
#include <stdlib.h>
#include <stdio.h>

void sum(int *b_avg, int *g_avg, int *r_avg, RGBTRIPLE pixel);

// Convert image to grayscale
void grayscale(int height, int width, RGBTRIPLE image[height][width])
{
    for (int i = 0; i < height; i++)
    {
        for (int j = 0; j < width; j++)
        {
            int avg = round((image[i][j].rgbtBlue + image[i][j].rgbtGreen + image[i][j].rgbtRed) / 3.0);
            image[i][j].rgbtBlue = avg;
            image[i][j].rgbtGreen = avg;
            image[i][j].rgbtRed = avg;
        }
    }
    return;
}

// Reflect image horizontally
void reflect(int height, int width, RGBTRIPLE image[height][width])
{
    for (int i = 0; i < height; i++)
    {
        for (int j = 0; j < round(width / 2); j++)
        {
            // swap j with width - j
            RGBTRIPLE temp = image[i][j];
            image[i][j] = image[i][width - (j + 1)];
            image[i][width - (j + 1)] = temp;
        }
    }
    return;
}

// Blur image
void blur(int height, int width, RGBTRIPLE image[height][width])
{
    RGBTRIPLE(*image_cp)[width] = calloc(height, width * sizeof(RGBTRIPLE));

    for (int i = 0; i < height; i++)
    {
        for (int j = 0; j < width; j++)
        {
            image_cp[i][j] = image[i][j];
        }
    }

    for (int i = 0; i < height; i++)
    {
        for (int j = 0; j < width; j++)
        {
            int b_avg, g_avg, r_avg = 0;
            int pixel_count = 0;
            for (int c = -1; c < 2; c++)
            {
                if (i + c < 0 || i + c >= height)
                {
                    continue;
                }
                for (int r = -1; r < 2; r++)
                {
                    if (j + r < 0 || j + r >= width)
                    {
                        continue;
                    }
                    sum(&b_avg, &g_avg, &r_avg, image_cp[i + c][j + r]);
                    pixel_count++;
                }
            }

            RGBTRIPLE avg;
            avg.rgbtBlue = b_avg / pixel_count;
            avg.rgbtGreen = g_avg / pixel_count;
            avg.rgbtRed = r_avg / pixel_count;

            image[i][j] = avg;
        }
    }
    free(image_cp);
    return;
}

// Detect edges
void edges(int height, int width, RGBTRIPLE image[height][width])
{
    return;
}

// adds rgb triple to averages
void sum(int *b_avg, int *g_avg, int *r_avg, RGBTRIPLE pixel)
{
    *b_avg += pixel.rgbtBlue;
    *g_avg += pixel.rgbtGreen;
    *r_avg += pixel.rgbtRed;
}