transformations.py 文件源码

def minor_rotation(x, z):
    """
    Assuming a batch size of 1.
    More specifically: x is (1, depth, channels, height, width) and z is (1, height*width*depth, classes)
    """
    from scipy.ndimage.interpolation import rotate as rotate_scipy
    from breze.learn.data import one_hot
    z_original_shape = z.shape
    n_classes = z.shape[-1]
    ang = float(np.random.uniform(-90, 90))
    axes = np.random.permutation(3)[:2]

    nx = np.transpose(x, (0, 2, 3, 4, 1))
    nz = np.reshape(z, (1, x.shape[3], x.shape[4], x.shape[1], n_classes))
    nz = np.transpose(nz, (0, 4, 1, 2, 3))

    nx[0] = [rotate_scipy(modality, ang, axes=axes, order=3, reshape=False) for modality in nx[0]]
    nx = np.transpose(nx, (0, 4, 1, 2, 3))
    nz[0] = [rotate_scipy(class_map, ang, axes=axes, order=3, reshape=False) for class_map in nz[0]]
    nz = nz[0].argmax(axis=0)
    nz = np.reshape(nz, (-1,))
    nz = np.reshape(one_hot(nz, n_classes), z_original_shape)

    nx = np.asarray(nx, dtype=x.dtype)
    nz = np.asarray(nz, dtype=z.dtype)

    return (nx, nz)