tools.py 文件源码

def add_cifar_10(x, x_cifar_10, sh=True):
    """Add cifar 10 as background."""
    sz = x.shape
    mask = (x == 0) * 1.
    # binarize cifar
    back = x_cifar_10.reshape(x_cifar_10.shape[0], 3, 32, 32).mean(1)
    back = back[:, 2:30, 2:30]  # take 28x28 from the center.
    back /= 255.
    back = back.astype(np.float32)

    # shuffle the index
    if sh:
        ind = np.random.randint(0, x_cifar_10.shape[0], sz[0])  # the index
        for i in range(10):
            np.random.shuffle(ind)
    else:
        # used only to plot images for paper.
        assert x_cifar_10.shape[0] == sz[0]
        ind = np.arange(0,  sz[0])  # the index
    back_sh = back[ind]
    back_sh = back_sh.reshape(back_sh.shape[0], -1)
    back_ready = np.multiply(back_sh, mask)
    out = np.clip(x + back_ready, 0., 1.)
    return out