void negativeFilter(unsigned char* image, unsigned int width, unsigned int height, unsigned int channels)
{
    for (unsigned int y = 0; y < height; y++)
    {
        for (unsigned int x = 0; x < width; x++)
        {
            for (unsigned int c = 0; c < channels; c++)
            {
                // Invert the pixel value
                image[(y * width + x) * channels + c] = 255 - image[(y * width + x) * channels + c];
            }
        }
    }
}

// Load the input image
std::vector<unsigned char> image;
unsigned int width, height;
unsigned error = lodepng::decode(image, width, height, "input.png");
if (error)
{
    std::cerr << "Error decoding PNG: " << lodepng_error_text(error) << std::endl;
    return;
}

// Apply the negative filter
negativeFilter(image.data(), width, height, 4);

// Save the output image
error = lodepng::encode("output.png", image, width, height);
if (error)
{
    std::cerr << "Error encoding PNG: " << lodepng_error_text(error) << std::endl;
    return;
}

std::cout << "Image processed successfully!" << std::endl;