Image area size calculator using resolutions and screen size

areasizecalc.cpp

/**
* Image area size calculator.
*
* This code can be used to calculate the area size of an image in squared centimeters.
*
* @author Steven Liebregt <stevenliebregt@outlook.com>
* @version 1.0.0
* @date 2018/04/06
*/

#include <iostream>
#include <cmath>

using namespace std;

/**
 * Calculate the diagonal pixel size using the width and the height in pixels.
 *
 * @since 1.0.0
 * @param width Width in pixels.
 * @param height Height in pixels.
 * @return The diagonal pixel size.
 */
double calculateDiagonalPixels(int width, int height)
{
    double widthPixelPower = pow(width, 2);
    double heightPixelPower = pow(height, 2);

    return sqrt(widthPixelPower + heightPixelPower);
}

/**
 * Calculate pixels per inch.
 *
 * @since 1.0.0
 * @param diagonalPixel Diagonal size in pixels.
 * @param diagonalInch Diagonal size in inches.
 * @return The amount of pixels per inch.
 */
double calculatePixelPerInch(double diagonalPixel, double diagonalInch)
{
    return diagonalPixel / diagonalInch;
}

/**
 * Calculate the amount of inches per pixel.
 *
 * @since 1.0.0
 * @param pixelsPerInch The amount of pixels per inch.
 * @return The amount of inches per pixel.
 */
double calculateInchPerPixel(double pixelsPerInch)
{
    return 1 / pixelsPerInch;
}

/**
 * Convert the pixels to inches.
 *
 * @since 1.0.0
 * @param inchPerPixel The amount of inches per pixel.
 * @param pixels The amount of pixels.
 * @return Inches instead of pixels.
 */
double convertPixelsToInches(double inchPerPixel, double pixels)
{
    cout << inchPerPixel << endl;
    cout << pixels << endl;
    return inchPerPixel * pixels;
}

/**
 * Convert inches to centimeters.
 *
 * @since 1.0.0
 * @param inches The amount of inches.
 * @return The amount of pixels instead of inches.
 */
double convertInchesToCm(double inches)
{
    return inches * 2.54;
}

/**
 * Calculate the area size by multiplying the width with the height.
 *
 * @since 1.0.0
 * @param width The width.
 * @param height The height.
 * @return The area size.
 */
double calculateAreaSize(double width, double height)
{
    return width * height;
}

/**
* Main function to calculate the area size in cm2
*
* @since 1.0.0
* @return
*/
int main()
{
    int screenWidthPixels; // Screen width in pixels
    int screenHeightPixels; // Screen height in pixels
    int imageWidthPixels; // Image width in pixels
    int imageHeightPixels; // Image height in pixels
    double screenDiagonalInch; // Diagonal size in inches

    // Get the screen width and height
    printf("Give the screen resolution in pixels (width, height) in the following form [1920x1080]: \n");
    scanf("%dx%d", &screenWidthPixels, &screenHeightPixels);

    // Get the diagonal inch in sizes of the screen
    printf("Give the screen diagonal size in inches: \n");
    scanf("%lf", &screenDiagonalInch);

    // Get the image width and height
    printf("Give the image resolution in pixels (width, height) in the following form [640x480]: \n");
    scanf("%dx%d", &imageWidthPixels, &imageHeightPixels);

    // Calculate the pixels per inch
    double pixelsPerInch = calculatePixelPerInch(calculateDiagonalPixels(screenWidthPixels, screenHeightPixels), screenDiagonalInch);

    // Calculate the inches per pixel
    double inchPerPixel = calculateInchPerPixel(pixelsPerInch);

    // Calculate the width in inches and then to centimeters
    double imageWidthInches = convertPixelsToInches(inchPerPixel, imageWidthPixels);
    double imageWidthCentimeters = convertInchesToCm(imageWidthInches);

    // Calculate the height in inches and then to centimeters
    double imageHeightInches = convertPixelsToInches(inchPerPixel, imageHeightPixels);
    double imageHeightCentimeters = convertInchesToCm(imageHeightInches);

    // Calculate area size
    double area = calculateAreaSize(imageWidthCentimeters, imageHeightCentimeters);

    // Output the results
    printf("Screen resolution: %dx%d \n", screenWidthPixels, screenHeightPixels);
    printf("Screen diagonal (inches): %lf \n", screenDiagonalInch);
    printf("\n");

    printf("Image resolution: %dx%d \n", imageWidthPixels, imageHeightPixels);
    printf("Image width (inches): %lf \n", imageWidthInches);
    printf("Image height (inches): %lf \n", imageHeightInches);
    printf("Image width (centimeters): %lf \n", imageWidthCentimeters);
    printf("Image height (centimeters): %lf \n", imageHeightCentimeters);
    printf("\n");

    printf("Pixels per inch: %lf \n", pixelsPerInch);
    printf("Inches per pixel: %lf \n", inchPerPixel);
    printf("\n");

    printf("Surface area (cm2): %.2lf \n", area);

    return 0;
}