Python numpy.uint8() Examples

def parse_data(path, dataset, flatten):
    if dataset != 'train' and dataset != 't10k':
        raise NameError('dataset must be train or t10k')

    label_file = os.path.join(path, dataset + '-labels-idx1-ubyte')
    with open(label_file, 'rb') as file:
        _, num = struct.unpack(">II", file.read(8))
        labels = np.fromfile(file, dtype=np.int8)  # int8
        new_labels = np.zeros((num, 10))
        new_labels[np.arange(num), labels] = 1

    img_file = os.path.join(path, dataset + '-images-idx3-ubyte')
    with open(img_file, 'rb') as file:
        _, num, rows, cols = struct.unpack(">IIII", file.read(16))
        imgs = np.fromfile(file, dtype=np.uint8).reshape(num, rows, cols)  # uint8
        imgs = imgs.astype(np.float32) / 255.0
        if flatten:
            imgs = imgs.reshape([num, -1])

    return imgs, new_labels 

def test_bitmap_mask_resize():
    # resize with empty bitmap masks
    raw_masks = dummy_raw_bitmap_masks((0, 28, 28))
    bitmap_masks = BitmapMasks(raw_masks, 28, 28)
    resized_masks = bitmap_masks.resize((56, 72))
    assert len(resized_masks) == 0
    assert resized_masks.height == 56
    assert resized_masks.width == 72

    # resize with bitmap masks contain 1 instances
    raw_masks = np.diag(np.ones(4, dtype=np.uint8))[np.newaxis, ...]
    bitmap_masks = BitmapMasks(raw_masks, 4, 4)
    resized_masks = bitmap_masks.resize((8, 8))
    assert len(resized_masks) == 1
    assert resized_masks.height == 8
    assert resized_masks.width == 8
    truth = np.array([[[1, 1, 0, 0, 0, 0, 0, 0], [1, 1, 0, 0, 0, 0, 0, 0],
                       [0, 0, 1, 1, 0, 0, 0, 0], [0, 0, 1, 1, 0, 0, 0, 0],
                       [0, 0, 0, 0, 1, 1, 0, 0], [0, 0, 0, 0, 1, 1, 0, 0],
                       [0, 0, 0, 0, 0, 0, 1, 1], [0, 0, 0, 0, 0, 0, 1, 1]]])
    assert (resized_masks.masks == truth).all() 

def test_ndarray_elementwise():
    np.random.seed(0)
    nrepeat = 10
    maxdim = 4
    all_type = [np.float32, np.float64, np.float16, np.uint8, np.int32]
    real_type = [np.float32, np.float64, np.float16]
    for repeat in range(nrepeat):
        for dim in range(1, maxdim):
            check_with_uniform(lambda x, y: x + y, 2, dim, type_list=all_type)
            check_with_uniform(lambda x, y: x - y, 2, dim, type_list=all_type)
            check_with_uniform(lambda x, y: x * y, 2, dim, type_list=all_type)
            check_with_uniform(lambda x, y: x / y, 2, dim, type_list=real_type)
            check_with_uniform(lambda x, y: x / y, 2, dim, rmin=1, type_list=all_type)
            check_with_uniform(mx.nd.sqrt, 1, dim, np.sqrt, rmin=0)
            check_with_uniform(mx.nd.square, 1, dim, np.square, rmin=0)
            check_with_uniform(lambda x: mx.nd.norm(x).asscalar(), 1, dim, np.linalg.norm) 

def create_mnistrgb(tfrecord_dir, mnist_dir, num_images=1000000, random_seed=123):
    print('Loading MNIST from "%s"' % mnist_dir)
    import gzip
    with gzip.open(os.path.join(mnist_dir, 'train-images-idx3-ubyte.gz'), 'rb') as file:
        images = np.frombuffer(file.read(), np.uint8, offset=16)
    images = images.reshape(-1, 28, 28)
    images = np.pad(images, [(0,0), (2,2), (2,2)], 'constant', constant_values=0)
    assert images.shape == (60000, 32, 32) and images.dtype == np.uint8
    assert np.min(images) == 0 and np.max(images) == 255
    
    with TFRecordExporter(tfrecord_dir, num_images) as tfr:
        rnd = np.random.RandomState(random_seed)
        for idx in range(num_images):
            tfr.add_image(images[rnd.randint(images.shape[0], size=3)])

#---------------------------------------------------------------------------- 

def create_mnist(tfrecord_dir, mnist_dir):
    print('Loading MNIST from "%s"' % mnist_dir)
    import gzip
    with gzip.open(os.path.join(mnist_dir, 'train-images-idx3-ubyte.gz'), 'rb') as file:
        images = np.frombuffer(file.read(), np.uint8, offset=16)
    with gzip.open(os.path.join(mnist_dir, 'train-labels-idx1-ubyte.gz'), 'rb') as file:
        labels = np.frombuffer(file.read(), np.uint8, offset=8)
    images = images.reshape(-1, 1, 28, 28)
    images = np.pad(images, [(0,0), (0,0), (2,2), (2,2)], 'constant', constant_values=0)
    assert images.shape == (60000, 1, 32, 32) and images.dtype == np.uint8
    assert labels.shape == (60000,) and labels.dtype == np.uint8
    assert np.min(images) == 0 and np.max(images) == 255
    assert np.min(labels) == 0 and np.max(labels) == 9
    onehot = np.zeros((labels.size, np.max(labels) + 1), dtype=np.float32)
    onehot[np.arange(labels.size), labels] = 1.0
    
    with TFRecordExporter(tfrecord_dir, images.shape[0]) as tfr:
        order = tfr.choose_shuffled_order()
        for idx in range(order.size):
            tfr.add_image(images[order[idx]])
        tfr.add_labels(onehot[order])

#---------------------------------------------------------------------------- 

def add_image(self, img):
        if self.print_progress and self.cur_images % self.progress_interval == 0:
            print('%d / %d\r' % (self.cur_images, self.expected_images), end='', flush=True)
            sys.stdout.flush()
        if self.shape is None:
            self.shape = img.shape
            self.resolution_log2 = int(np.log2(self.shape[1]))
            assert self.shape[0] in [1, 3]
            assert self.shape[1] == self.shape[2]
            assert self.shape[1] == 2**self.resolution_log2
            tfr_opt = tf.python_io.TFRecordOptions(tf.python_io.TFRecordCompressionType.NONE)
            for lod in range(self.resolution_log2 - 1):
                tfr_file = self.tfr_prefix + '-r%02d.tfrecords' % (self.resolution_log2 - lod)
                self.tfr_writers.append(tf.python_io.TFRecordWriter(tfr_file, tfr_opt))
        assert img.shape == self.shape
        for lod, tfr_writer in enumerate(self.tfr_writers):
            if lod:
                img = img.astype(np.float32)
                img = (img[:, 0::2, 0::2] + img[:, 0::2, 1::2] + img[:, 1::2, 0::2] + img[:, 1::2, 1::2]) * 0.25
            quant = np.rint(img).clip(0, 255).astype(np.uint8)
            ex = tf.train.Example(features=tf.train.Features(feature={
                'shape': tf.train.Feature(int64_list=tf.train.Int64List(value=quant.shape)),
                'data': tf.train.Feature(bytes_list=tf.train.BytesList(value=[quant.tostring()]))}))
            tfr_writer.write(ex.SerializeToString())
        self.cur_images += 1 

def create_cifar100(tfrecord_dir, cifar100_dir):
    print('Loading CIFAR-100 from "%s"' % cifar100_dir)
    import pickle
    with open(os.path.join(cifar100_dir, 'train'), 'rb') as file:
        data = pickle.load(file, encoding='latin1')
    images = data['data'].reshape(-1, 3, 32, 32)
    labels = np.array(data['fine_labels'])
    assert images.shape == (50000, 3, 32, 32) and images.dtype == np.uint8
    assert labels.shape == (50000,) and labels.dtype == np.int32
    assert np.min(images) == 0 and np.max(images) == 255
    assert np.min(labels) == 0 and np.max(labels) == 99
    onehot = np.zeros((labels.size, np.max(labels) + 1), dtype=np.float32)
    onehot[np.arange(labels.size), labels] = 1.0

    with TFRecordExporter(tfrecord_dir, images.shape[0]) as tfr:
        order = tfr.choose_shuffled_order()
        for idx in range(order.size):
            tfr.add_image(images[order[idx]])
        tfr.add_labels(onehot[order])

#---------------------------------------------------------------------------- 

def draw_heatmap(img, heatmap, alpha=0.5):
    """Draw a heatmap overlay over an image."""
    assert len(heatmap.shape) == 2 or \
        (len(heatmap.shape) == 3 and heatmap.shape[2] == 1)
    assert img.dtype in [np.uint8, np.int32, np.int64]
    assert heatmap.dtype in [np.float32, np.float64]

    if img.shape[0:2] != heatmap.shape[0:2]:
        heatmap_rs = np.clip(heatmap * 255, 0, 255).astype(np.uint8)
        heatmap_rs = ia.imresize_single_image(
            heatmap_rs[..., np.newaxis],
            img.shape[0:2],
            interpolation="nearest"
        )
        heatmap = np.squeeze(heatmap_rs) / 255.0

    cmap = plt.get_cmap('jet')
    heatmap_cmapped = cmap(heatmap)
    heatmap_cmapped = np.delete(heatmap_cmapped, 3, 2)
    heatmap_cmapped = heatmap_cmapped * 255
    mix = (1-alpha) * img + alpha * heatmap_cmapped
    mix = np.clip(mix, 0, 255).astype(np.uint8)
    return mix 

def z_color(self, z):
        z = float(z)
        alpha = 1.0

        if z <= self.mid_z:
            ns = lerp(z, self.near_z, self.mid_z)
            color = (1.0 - ns) * self.near_color + ns * self.mid_color
        else:  # z must be between self.mid_z and FAR_Z
            fs = lerp(z, self.mid_z, self.far_z)
            color = (1.0 - fs) * self.mid_color + fs * self.far_color

        alpha = 1.0 - lerp(z, self.min_z, self.max_z)

        if z <= -self.min_z:
            alpha = 0.0

        # gl_FragColor = vec4(color, alpha) * texture2D( texture, gl_PointCoord )

        return (color * alpha).astype(np.uint8).tolist() 

def __init__(self, batch_size, input_length, nthreads=6, web_viz=False):
        super(RLDataIter, self).__init__()
        self.batch_size = batch_size
        self.input_length = input_length
        self.env = [self.make_env() for _ in range(batch_size)]
        self.act_dim = self.env[0].action_space.n

        self.state_ = None

        self.reset()

        self.provide_data = [mx.io.DataDesc('data', self.state_.shape, np.uint8)]

        self.web_viz = web_viz
        if web_viz:
            self.queue = queue.Queue()
            self.thread = Thread(target=make_web, args=(self.queue,))
            self.thread.daemon = True
            self.thread.start()

        self.nthreads = nthreads
        if nthreads > 1:
            self.pool = multiprocessing.pool.ThreadPool(6) 

def _get_data(self):
        if self._train:
            data, label = self._train_data, self._train_label
        else:
            data, label = self._test_data, self._test_label

        namespace = 'gluon/dataset/'+self._namespace
        data_file = download(_get_repo_file_url(namespace, data[0]),
                             path=self._root,
                             sha1_hash=data[1])
        label_file = download(_get_repo_file_url(namespace, label[0]),
                              path=self._root,
                              sha1_hash=label[1])

        with gzip.open(label_file, 'rb') as fin:
            struct.unpack(">II", fin.read(8))
            label = np.frombuffer(fin.read(), dtype=np.uint8).astype(np.int32)

        with gzip.open(data_file, 'rb') as fin:
            struct.unpack(">IIII", fin.read(16))
            data = np.frombuffer(fin.read(), dtype=np.uint8)
            data = data.reshape(len(label), 28, 28, 1)

        self._data = nd.array(data, dtype=data.dtype)
        self._label = label 

def wer(self, r, h):
        # initialisation
        d = np.zeros((len(r)+1)*(len(h)+1), dtype=np.uint8)
        d = d.reshape((len(r)+1, len(h)+1))
        for i in range(len(r)+1):
            for j in range(len(h)+1):
                if i == 0:
                    d[0][j] = j
                elif j == 0:
                    d[i][0] = i

        # computation
        for i in range(1, len(r)+1):
            for j in range(1, len(h)+1):
                if r[i-1] == h[j-1]:
                    d[i][j] = d[i-1][j-1]
                else:
                    substitution = d[i-1][j-1] + 1
                    insertion    = d[i][j-1] + 1
                    deletion     = d[i-1][j] + 1
                    d[i][j] = min(substitution, insertion, deletion)

        return d[len(r)][len(h)] 

def draw_bounding_boxes(image, gt_boxes, im_info):
  num_boxes = gt_boxes.shape[0]
  gt_boxes_new = gt_boxes.copy()
  gt_boxes_new[:,:4] = np.round(gt_boxes_new[:,:4].copy() / im_info[2])
  disp_image = Image.fromarray(np.uint8(image[0]))

  for i in range(num_boxes):
    this_class = int(gt_boxes_new[i, 4])
    disp_image = _draw_single_box(disp_image, 
                                gt_boxes_new[i, 0],
                                gt_boxes_new[i, 1],
                                gt_boxes_new[i, 2],
                                gt_boxes_new[i, 3],
                                'N%02d-C%02d' % (i, this_class),
                                FONT,
                                color=STANDARD_COLORS[this_class % NUM_COLORS])

  image[0, :] = np.array(disp_image)
  return image 

def save_image(data, epoch, image_size, batch_size, output_dir, padding=2):
    """ save image """
    data = data.asnumpy().transpose((0, 2, 3, 1))
    datanp = np.clip(
        (data - np.min(data))*(255.0/(np.max(data) - np.min(data))), 0, 255).astype(np.uint8)
    x_dim = min(8, batch_size)
    y_dim = int(math.ceil(float(batch_size) / x_dim))
    height, width = int(image_size + padding), int(image_size + padding)
    grid = np.zeros((height * y_dim + 1 + padding // 2, width *
                     x_dim + 1 + padding // 2, 3), dtype=np.uint8)
    k = 0
    for y in range(y_dim):
        for x in range(x_dim):
            if k >= batch_size:
                break
            start_y = y * height + 1 + padding // 2
            end_y = start_y + height - padding
            start_x = x * width + 1 + padding // 2
            end_x = start_x + width - padding
            np.copyto(grid[start_y:end_y, start_x:end_x, :], datanp[k])
            k += 1
    imageio.imwrite(
        '{}/fake_samples_epoch_{}.png'.format(output_dir, epoch), grid) 

def resolve(ctx):
    from PIL import Image
    if isinstance(ctx, list):
        ctx = [ctx[0]]
    net.load_parameters('superres.params', ctx=ctx)
    img = Image.open(opt.resolve_img).convert('YCbCr')
    y, cb, cr = img.split()
    data = mx.nd.expand_dims(mx.nd.expand_dims(mx.nd.array(y), axis=0), axis=0)
    out_img_y = mx.nd.reshape(net(data), shape=(-3, -2)).asnumpy()
    out_img_y = out_img_y.clip(0, 255)
    out_img_y = Image.fromarray(np.uint8(out_img_y[0]), mode='L')

    out_img_cb = cb.resize(out_img_y.size, Image.BICUBIC)
    out_img_cr = cr.resize(out_img_y.size, Image.BICUBIC)
    out_img = Image.merge('YCbCr', [out_img_y, out_img_cb, out_img_cr]).convert('RGB')

    out_img.save('resolved.png') 

def visual(title, X, activation):
    '''create a grid of images and save it as a final image
    title : grid image name
    X : array of images
    '''
    assert len(X.shape) == 4

    X = X.transpose((0, 2, 3, 1))
    if activation == 'sigmoid':
        X = np.clip((X)*(255.0), 0, 255).astype(np.uint8)
    elif activation == 'tanh':
        X = np.clip((X+1.0)*(255.0/2.0), 0, 255).astype(np.uint8)
    n = np.ceil(np.sqrt(X.shape[0]))
    buff = np.zeros((int(n*X.shape[1]), int(n*X.shape[2]), int(X.shape[3])), dtype=np.uint8)
    for i, img in enumerate(X):
        fill_buf(buff, i, img, X.shape[1:3])
    cv2.imwrite('%s.jpg' % (title), buff) 

def generate_fake_images(run_id, snapshot=None, grid_size=[1,1], num_pngs=1, image_shrink=1, png_prefix=None, random_seed=1000, minibatch_size=8):
    network_pkl = misc.locate_network_pkl(run_id, snapshot)
    if png_prefix is None:
        png_prefix = misc.get_id_string_for_network_pkl(network_pkl) + '-'
    random_state = np.random.RandomState(random_seed)

    print('Loading network from "%s"...' % network_pkl)
    G, D, Gs = misc.load_network_pkl(run_id, snapshot)

    result_subdir = misc.create_result_subdir(config.result_dir, config.desc)
    for png_idx in range(num_pngs):
        print('Generating png %d / %d...' % (png_idx, num_pngs))
        latents = misc.random_latents(np.prod(grid_size), Gs, random_state=random_state)
        labels = np.zeros([latents.shape[0], 0], np.float32)
        images = Gs.run(latents, labels, minibatch_size=minibatch_size, num_gpus=config.num_gpus, out_mul=127.5, out_add=127.5, out_shrink=image_shrink, out_dtype=np.uint8)
        misc.save_image_grid(images, os.path.join(result_subdir, '%s%06d.png' % (png_prefix, png_idx)), [0,255], grid_size)
    open(os.path.join(result_subdir, '_done.txt'), 'wt').close()

#----------------------------------------------------------------------------
# Generate MP4 video of random interpolations using a previously trained network.
# To run, uncomment the appropriate line in config.py and launch train.py. 

def show():
    """Output the contents of the buffer to Unicorn HAT HD."""
    setup()
    if _addressing_enabled:
        for address in range(8):
            display = _displays[address]
            if display.enabled:
                if _buffer_width == _buffer_height or _rotation in [0, 2]:
                    window = display.get_buffer_window(numpy.rot90(_buf, _rotation))
                else:
                    window = display.get_buffer_window(numpy.rot90(_buf, _rotation))

                _spi.xfer2([_SOF + 1 + address] + (window.reshape(768) * _brightness).astype(numpy.uint8).tolist())
                time.sleep(_DELAY)
    else:
        _spi.xfer2([_SOF] + (numpy.rot90(_buf, _rotation).reshape(768) * _brightness).astype(numpy.uint8).tolist())

    time.sleep(_DELAY) 

def __init__(self, resolution=1024, num_channels=3, dtype='uint8', dynamic_range=[0,255], label_size=0, label_dtype='float32'):
        self.resolution         = resolution
        self.resolution_log2    = int(np.log2(resolution))
        self.shape              = [num_channels, resolution, resolution]
        self.dtype              = dtype
        self.dynamic_range      = dynamic_range
        self.label_size         = label_size
        self.label_dtype        = label_dtype
        self._tf_minibatch_var  = None
        self._tf_lod_var        = None
        self._tf_minibatch_np   = None
        self._tf_labels_np      = None

        assert self.resolution == 2 ** self.resolution_log2
        with tf.name_scope('Dataset'):
            self._tf_minibatch_var = tf.Variable(np.int32(0), name='minibatch_var')
            self._tf_lod_var = tf.Variable(np.int32(0), name='lod_var') 

def __init__(self, dataset, oversample_thr):
        self.dataset = dataset
        self.oversample_thr = oversample_thr
        self.CLASSES = dataset.CLASSES

        repeat_factors = self._get_repeat_factors(dataset, oversample_thr)
        repeat_indices = []
        for dataset_index, repeat_factor in enumerate(repeat_factors):
            repeat_indices.extend([dataset_index] * math.ceil(repeat_factor))
        self.repeat_indices = repeat_indices

        flags = []
        if hasattr(self.dataset, 'flag'):
            for flag, repeat_factor in zip(self.dataset.flag, repeat_factors):
                flags.extend([flag] * int(math.ceil(repeat_factor)))
            assert len(flags) == len(repeat_indices)
        self.flag = np.asarray(flags, dtype=np.uint8) 

def __call__(self, results):
        """Call function to corrupt image.

        Args:
            results (dict): Result dict from loading pipeline.

        Returns:
            dict: Result dict with images corrupted.
        """

        if corrupt is None:
            raise RuntimeError('imagecorruptions is not installed')
        if 'img_fields' in results:
            assert results['img_fields'] == ['img'], \
                'Only single img_fields is allowed'
        results['img'] = corrupt(
            results['img'].astype(np.uint8),
            corruption_name=self.corruption,
            severity=self.severity)
        return results 

def tensor2imgs(tensor, mean=(0, 0, 0), std=(1, 1, 1), to_rgb=True):
    """Convert tensor to images.

    Args:
        tensor (torch.Tensor): Tensor that contains multiple images
        mean (tuple[float], optional): Mean of images. Defaults to (0, 0, 0).
        std (tuple[float], optional): Standard deviation of images.
            Defaults to (1, 1, 1).
        to_rgb (bool, optional): Whether convert the images to RGB format.
            Defaults to True.

    Returns:
        list[np.ndarray]: A list that contains multiple images.
    """
    num_imgs = tensor.size(0)
    mean = np.array(mean, dtype=np.float32)
    std = np.array(std, dtype=np.float32)
    imgs = []
    for img_id in range(num_imgs):
        img = tensor[img_id, ...].cpu().numpy().transpose(1, 2, 0)
        img = mmcv.imdenormalize(
            img, mean, std, to_bgr=to_rgb).astype(np.uint8)
        imgs.append(np.ascontiguousarray(img))
    return imgs 

def main():
    """Module main execution"""
    # Initialization variables - update to change your model and execution context
    model_prefix = "FCN8s_VGG16"
    epoch = 19

    # By default, MXNet will run on the CPU. Change to ctx = mx.gpu() to run on GPU.
    ctx = mx.cpu()

    fcnxs, fcnxs_args, fcnxs_auxs = mx.model.load_checkpoint(model_prefix, epoch)
    fcnxs_args["data"] = mx.nd.array(get_data(args.input), ctx)
    data_shape = fcnxs_args["data"].shape
    label_shape = (1, data_shape[2]*data_shape[3])
    fcnxs_args["softmax_label"] = mx.nd.empty(label_shape, ctx)
    exector = fcnxs.bind(ctx, fcnxs_args, args_grad=None, grad_req="null", aux_states=fcnxs_args)
    exector.forward(is_train=False)
    output = exector.outputs[0]
    out_img = np.uint8(np.squeeze(output.asnumpy().argmax(axis=1)))
    out_img = Image.fromarray(out_img)
    out_img.putpalette(get_palette())
    out_img.save(args.output) 

def crop(self, bbox):
        """See :func:`BaseInstanceMasks.crop`."""
        assert isinstance(bbox, np.ndarray)
        assert bbox.ndim == 1

        # clip the boundary
        bbox = bbox.copy()
        bbox[0::2] = np.clip(bbox[0::2], 0, self.width)
        bbox[1::2] = np.clip(bbox[1::2], 0, self.height)
        x1, y1, x2, y2 = bbox
        w = np.maximum(x2 - x1, 1)
        h = np.maximum(y2 - y1, 1)

        if len(self.masks) == 0:
            cropped_masks = np.empty((0, h, w), dtype=np.uint8)
        else:
            cropped_masks = self.masks[:, y1:y1 + h, x1:x1 + w]
        return BitmapMasks(cropped_masks, h, w) 

def show(image):
    """
    Render a given numpy.uint8 2D array of pixel data.
    """
    plt.imshow(image, cmap='gray')
    plt.show() 

def Chainer2PIL(data, rescale=True):
    data = np.array(data)
    if rescale:
        data *= 256
        # data += 128
    if data.dtype != np.uint8:
        data = np.clip(data, 0, 255)
        data = data.astype(np.uint8)
    if data.shape[0] == 1:
        buf = data.astype(np.uint8).reshape((data.shape[1], data.shape[2]))
    else:
        buf = np.zeros((data.shape[1], data.shape[2], data.shape[0]), dtype=np.uint8)
        for i in range(3):
            a = data[i,:,:]
            buf[:,:,i] = a
    img = Image.fromarray(buf)
    return img 

def test_load_multi_channel_img(self):
        results = dict(
            img_prefix=self.data_prefix,
            img_info=dict(filename=['color.jpg', 'color.jpg']))
        transform = LoadMultiChannelImageFromFiles()
        results = transform(copy.deepcopy(results))
        assert results['filename'] == [
            osp.join(self.data_prefix, 'color.jpg'),
            osp.join(self.data_prefix, 'color.jpg')
        ]
        assert results['ori_filename'] == ['color.jpg', 'color.jpg']
        assert results['img'].shape == (288, 512, 3, 2)
        assert results['img'].dtype == np.uint8
        assert results['img_shape'] == (288, 512, 3, 2)
        assert results['ori_shape'] == (288, 512, 3, 2)
        assert results['pad_shape'] == (288, 512, 3, 2)
        assert results['scale_factor'] == 1.0
        assert repr(transform) == transform.__class__.__name__ + \
            "(to_float32=False, color_type='unchanged', " + \
            "file_client_args={'backend': 'disk'})" 

def _prepare_sample_data(self, submission_type):
    """Prepares sample data for the submission.

    Args:
      submission_type: type of the submission.
    """
    # write images
    images = np.random.randint(0, 256,
                               size=[BATCH_SIZE, 299, 299, 3], dtype=np.uint8)
    for i in range(BATCH_SIZE):
      Image.fromarray(images[i, :, :, :]).save(
          os.path.join(self._sample_input_dir, IMAGE_NAME_PATTERN.format(i)))
    # write target class for targeted attacks
    if submission_type == 'targeted_attack':
      target_classes = np.random.randint(1, 1001, size=[BATCH_SIZE])
      target_class_filename = os.path.join(self._sample_input_dir,
                                           'target_class.csv')
      with open(target_class_filename, 'w') as f:
        for i in range(BATCH_SIZE):
          f.write((IMAGE_NAME_PATTERN + ',{1}\n').format(i, target_classes[i])) 

def save_images(images, filenames, output_dir):
  """Saves images to the output directory.

  Args:
    images: array with minibatch of images
    filenames: list of filenames without path
      If number of file names in this list less than number of images in
      the minibatch then only first len(filenames) images will be saved.
    output_dir: directory where to save images
  """
  for i, filename in enumerate(filenames):
    # Images for inception classifier are normalized to be in [-1, 1] interval,
    # so rescale them back to [0, 1].
    with tf.gfile.Open(os.path.join(output_dir, filename), 'w') as f:
      img = (((images[i, :, :, :] + 1.0) * 0.5) * 255.0).astype(np.uint8)
      Image.fromarray(img).save(f, format='PNG') 

def _prepare_sample_data(self, submission_type):
    """Prepares sample data for the submission.

    Args:
      submission_type: type of the submission.
    """
    # write images
    images = np.random.randint(0, 256,
                               size=[BATCH_SIZE, 299, 299, 3], dtype=np.uint8)
    for i in range(BATCH_SIZE):
      Image.fromarray(images[i, :, :, :]).save(
          os.path.join(self._sample_input_dir, IMAGE_NAME_PATTERN.format(i)))
    # write target class for targeted attacks
    if submission_type == 'targeted_attack':
      target_classes = np.random.randint(1, 1001, size=[BATCH_SIZE])
      target_class_filename = os.path.join(self._sample_input_dir,
                                           'target_class.csv')
      with open(target_class_filename, 'w') as f:
        for i in range(BATCH_SIZE):
          f.write((IMAGE_NAME_PATTERN + ',{1}\n').format(i, target_classes[i]))