Questions about some codes

[cxy2333-hue]

In your code:
` def add_noise(self, img: mge.Tensor) -> Tuple[mge.Tensor, float]:
"""
Args:
- img: [-black, camera_value_scale]

    Returns:
        - noisy_img
        - iso
    """

    N = img.shape[0]
    isos = np.random.uniform(*self.opts.iso_range, size=(N, ))
    k, b = self.noise_func(isos, value_scale=self.opts.camera_value_scale)
    k = k.reshape(-1, 1, 1, 1)
    b = b.reshape(-1, 1, 1, 1)

    shot_noisy = megengine.random.poisson((img / k).clip(0, 1)) * k
    read_noisy = megengine.random.normal(size=img.shape) * math.sqrt(b)
    noisy = shot_noisy + read_noisy
    noisy = F.round(noisy)

    return noisy

It seems that clip(0,1) should not be used in the codeshot_noisy = megengine.random.poisson((img / k).clip(0, 1)) * k`, since most of (img / k)'s range is not between 0 and 1