def noise_map_from_inverse_noise_map(inverse_noise_map):
    """Setup the noise map from an inverse noise map.

    The variance in each pixel is computed as:

    Variance = 1.0 / inverse_noise_map.

    Parameters
    -----------
    inverse_noise_map : ndarray
        The inverse noise_map value of each pixel which is converted to a variance.
    """
    return 1.0 / inverse_noise_map
