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@kinoute
Created June 10, 2020 21:04
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Harvard CS50 filters
#include "helpers.h"
#include <stdio.h>
#include <math.h>
// 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 = (image[i][j].rgbtRed + image[i][j].rgbtBlue + image[i][j].rgbtGreen) / 3;
image[i][j].rgbtRed = avg;
image[i][j].rgbtBlue = avg;
image[i][j].rgbtGreen = avg;
}
}
return;
}
// Convert image to sepia
void sepia(int height, int width, RGBTRIPLE image[height][width])
{
for (int i = 0; i < height; i++)
{
for (int j = 0; j < width; j++)
{
float sepiaRed = .393 * image[i][j].rgbtRed + .769 * image[i][j].rgbtGreen + .189 * image[i][j].rgbtBlue;
float sepiaGreen = .349 * image[i][j].rgbtRed + .686 * image[i][j].rgbtGreen + .168 * image[i][j].rgbtBlue;
float sepiaBlue = .272 * image[i][j].rgbtRed + .534 * image[i][j].rgbtGreen + .131 * image[i][j].rgbtBlue;
image[i][j].rgbtRed = (int) (sepiaRed <= 255) ? sepiaRed : 255;
image[i][j].rgbtBlue = (int) (sepiaBlue <= 255) ? sepiaBlue : 255;
image[i][j].rgbtGreen = (int) (sepiaGreen <= 255) ? sepiaGreen : 255;
}
}
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 < width / 2; j++) {
int tempRed = image[i][j].rgbtRed;
int tempBlue = image[i][j].rgbtBlue;
int tempGreen = image[i][j].rgbtGreen;
image[i][j].rgbtRed = image[i][width - 1 - j].rgbtRed;
image[i][width - 1 - j].rgbtRed = tempRed;
image[i][j].rgbtGreen = image[i][width - 1 - j].rgbtGreen;
image[i][width - 1 - j].rgbtGreen = tempGreen;
image[i][j].rgbtBlue = image[i][width - 1 - j].rgbtBlue;
image[i][width - 1 - j].rgbtBlue = tempBlue;
}
}
return;
}
// Blur image
void blur(int height, int width, RGBTRIPLE image[height][width])
{
RGBTRIPLE ogImage[height][width];
for (int i = 0; i < height; i++)
{
for (int j = 0; j < width; j++)
{
ogImage[i][j] = image[i][j];
}
}
for (int i = 0, red, green, blue, counter; i < height; i++)
{
for (int j = 0; j < width; j++)
{
red = green = blue = counter = 0;
if (i >= 0 && j >= 0)
{
red += ogImage[i][j].rgbtRed;
green += ogImage[i][j].rgbtGreen;
blue += ogImage[i][j].rgbtBlue;
counter++;
}
if (i >= 0 && j - 1 >= 0)
{
red += ogImage[i][j-1].rgbtRed;
green += ogImage[i][j-1].rgbtGreen;
blue += ogImage[i][j-1].rgbtBlue;
counter++;
}
if ((i >= 0 && j + 1 >= 0) && (i >= 0 && j + 1 < width))
{
red += ogImage[i][j+1].rgbtRed;
green += ogImage[i][j+1].rgbtGreen;
blue += ogImage[i][j+1].rgbtBlue;
counter++;
}
if (i - 1 >= 0 && j >= 0)
{
red += ogImage[i-1][j].rgbtRed;
green += ogImage[i-1][j].rgbtGreen;
blue += ogImage[i-1][j].rgbtBlue;
counter++;
}
if (i - 1 >= 0 && j - 1 >= 0)
{
red += ogImage[i-1][j-1].rgbtRed;
green += ogImage[i-1][j-1].rgbtGreen;
blue += ogImage[i-1][j-1].rgbtBlue;
counter++;
}
if ((i - 1 >= 0 && j + 1 >= 0) && (i - 1 >= 0 && j + 1 < width))
{
red += ogImage[i-1][j+1].rgbtRed;
green += ogImage[i-1][j+1].rgbtGreen;
blue += ogImage[i-1][j+1].rgbtBlue;
counter++;
}
if ((i + 1 >= 0 && j >= 0) && (i + 1 < height && j >= 0))
{
red += ogImage[i+1][j].rgbtRed;
green += ogImage[i+1][j].rgbtGreen;
blue += ogImage[i+1][j].rgbtBlue;
counter++;
}
if ((i + 1 >= 0 && j - 1 >= 0) && (i + 1 < height && j - 1 >= 0))
{
red += ogImage[i+1][j-1].rgbtRed;
green += ogImage[i+1][j-1].rgbtGreen;
blue += ogImage[i+1][j-1].rgbtBlue;
counter++;
}
if ((i + 1 >= 0 && j + 1 >= 0) && (i + 1 < height && j + 1 < width))
{
red += ogImage[i+1][j+1].rgbtRed;
green += ogImage[i+1][j+1].rgbtGreen;
blue += ogImage[i+1][j+1].rgbtBlue;
counter++;
}
image[i][j].rgbtRed = round(red / (counter * 1.0));
image[i][j].rgbtGreen = round(green / (counter * 1.0));
image[i][j].rgbtBlue = round(blue / (counter * 1.0));
}
}
return;
}
@AMMADDIN470
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can u please tell me what is this this for filter less or more??

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