// Copyright (c) Radzivon Bartoshyk. All rights reserved.
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pub fn get_gaussian_kernel_1d(width: u32, sigma: f32) -> Vec<f32> {
    let mut sum_norm: f32 = 0f32;
    let mut kernel: Vec<f32> = Vec::with_capacity(width as usize);
    let scale = 1f32 / (f32::sqrt(2f32 * std::f32::consts::PI) * sigma);
    let mean = (width / 2) as f32;

    for x in 0..width {
        let new_weight = f32::exp(-0.5f32 * f32::powf((x as f32 - mean) / sigma, 2.0f32)) * scale;
        kernel.push(new_weight);
        sum_norm += new_weight;
    }

    if sum_norm != 0f32 {
        let sum_scale = 1f32 / sum_norm;
        for x in 0..width as usize {
            unsafe {
                *kernel.get_unchecked_mut(x) = (*kernel.get_unchecked(x)) * sum_scale;
            }
        }
    }

    kernel
}
