联邦学习图像分类数据集处理
本教程采用leaf数据集中的联邦学习数据集FEMNIST，该数据集包含62个不同类别的手写数字和字母（数字0~9、26个小写字母、26个大写字母），图像大小为28 x 28像素，数据集包含3500个用户的手写数字和字母（最多可模拟3500个客户端参与联邦学习），总数据量为805263，平均每个用户包含数据量为226.83，所有用户数据量的方差为88.94。
参考leaf数据集官方指导下载数据集。
下载数据集前的环境要求。
numpy==1.16.4 scipy # conda install scipy tensorflow==1.13.1 # pip install tensorflow Pillow # pip install Pillow matplotlib # pip install matplotlib jupyter # conda install jupyter notebook==5.7.8 tornado==4.5.3 pandas # pip install pandas
使用git下载官方数据集生成脚本。
git clone https://github.com/TalwalkarLab/leaf.git
下载项目后，目录结构如下：
leaf/data/femnist ├── data # 用来存放指令生成的数据集 ├── preprocess # 存放数据预处理的相关代码 ├── preprocess.sh # femnist数据集生成shell脚本 └── README.md # 官方数据集下载指导文档
以
femnist数据集为例，运行以下指令进入指定路径。cd leaf/data/femnist
用指令
./preprocess.sh -s niid --sf 1.0 -k 0 -t sample生成的数据集包含3500个用户，且按照9:1对每个用户的数据划分训练和测试集。指令中参数含义可参考
leaf/data/femnist/README.md文件中的说明。运行之后目录结构如下：
leaf/data/femnist/35_client_sf1_data/ ├── all_data # 所有数据集混合在一起，不区分训练测试集，共包含35个json文件，每个json文件包含100个用户的数据 ├── test # 按照9:1对每个用户的数据划分训练和测试集后的测试集，共包含35个json文件，每个json文件包含100个用户的数据 ├── train # 按照9:1对每个用户的数据划分训练和测试集后的训练集，共包含35个json文件，每个json文件包含100个用户的数据 └── ... # 其他文件，暂不需要用到，不作介绍其中每个json文件包含以下三个部分：
users: 用户列表。num_samples: 每个用户的样本数量列表。user_data: 一个以用户名为key，以它们各自的数据为value的字典对象；对于每个用户，数据表示为图像列表，每张图像表示为大小为784的整数列表（将28 x 28图像数组展平所得）。
在重新运行
preprocess.sh之前，请确保删除数据目录中的rem_user_data、sampled_data、test和train子文件夹。将35个json文件划分为3500个json文件（每个json文件代表一个用户）。
参考代码如下：
import os import json def mkdir(path): if not os.path.exists(path): os.mkdir(path) def partition_json(root_path, new_root_path): """ partition 35 json files to 3500 json file Each raw .json file is an object with 3 keys: 1. 'users', a list of users 2. 'num_samples', a list of the number of samples for each user 3. 'user_data', an object with user names as keys and their respective data as values; for each user, data is represented as a list of images, with each image represented as a size-784 integer list (flattened from 28 by 28) Each new .json file is an object with 3 keys: 1. 'user_name', the name of user 2. 'num_samples', the number of samples for the user 3. 'user_data', an dict object with 'x' as keys and their respective data as values; with 'y' as keys and their respective label as values; Args: root_path (str): raw root path of 35 json files new_root_path (str): new root path of 3500 json files """ paths = os.listdir(root_path) count = 0 file_num = 0 for i in paths: file_num += 1 file_path = os.path.join(root_path, i) print('======== process ' + str(file_num) + ' file: ' + str(file_path) + '======================') with open(file_path, 'r') as load_f: load_dict = json.load(load_f) users = load_dict['users'] num_users = len(users) num_samples = load_dict['num_samples'] for j in range(num_users): count += 1 print('---processing user: ' + str(count) + '---') cur_out = {'user_name': None, 'num_samples': None, 'user_data': {}} cur_user_id = users[j] cur_data_num = num_samples[j] cur_user_path = os.path.join(new_root_path, cur_user_id + '.json') cur_out['user_name'] = cur_user_id cur_out['num_samples'] = cur_data_num cur_out['user_data'].update(load_dict['user_data'][cur_user_id]) with open(cur_user_path, 'w') as f: json.dump(cur_out, f) f = os.listdir(new_root_path) print(len(f), ' users have been processed!') # partition train json files partition_json("leaf/data/femnist/35_client_sf1_data/train", "leaf/data/femnist/3500_client_json/train") # partition test json files partition_json("leaf/data/femnist/35_client_sf1_data/test", "leaf/data/femnist/3500_client_json/test")
其中
root_path为leaf/data/femnist/35_client_sf1_data/{train,test}，new_root_path自行设置，用于存放生成的3500个用户json文件，需分别对训练和测试文件夹进行处理。新生成的3500个用户json文件，每个文件均包含以下三个部分：
user_name: 用户名。num_samples: 用户的样本数。user_data: 一个以’x’为key，以用户数据为value的字典对象；以’y’为key，以用户数据对应的标签为value。
运行该脚本打印如下，代表运行成功：
======== process 1 file: /leaf/data/femnist/35_client_sf1_data/train/all_data_16_niid_0_keep_0_train_9.json====================== ---processing user: 1--- ---processing user: 2--- ---processing user: 3--- ......
将json文件转换为图片文件。
可参考如下代码：
import os import json import numpy as np from PIL import Image name_list = ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z' ] def mkdir(path): if not os.path.exists(path): os.mkdir(path) def json_2_numpy(img_size, file_path): """ read json file to numpy Args: img_size (list): contain three elements: the height, width, channel of image file_path (str): root path of 3500 json files return: image_numpy (numpy) label_numpy (numpy) """ # open json file with open(file_path, 'r') as load_f_train: load_dict = json.load(load_f_train) num_samples = load_dict['num_samples'] x = load_dict['user_data']['x'] y = load_dict['user_data']['y'] size = (num_samples, img_size[0], img_size[1], img_size[2]) image_numpy = np.array(x, dtype=np.float32).reshape(size) # mindspore doesn't support float64 and int64 label_numpy = np.array(y, dtype=np.int32) return image_numpy, label_numpy def json_2_img(json_path, save_path): """ transform single json file to images Args: json_path (str): the path json file save_path (str): the root path to save images """ data, label = json_2_numpy([28, 28, 1], json_path) for i in range(data.shape[0]): img = data[i] * 255 # PIL don't support the 0/1 image ,need convert to 0~255 image im = Image.fromarray(np.squeeze(img)) im = im.convert('L') img_name = str(label[i]) + '_' + name_list[label[i]] + '_' + str(i) + '.png' path1 = os.path.join(save_path, str(label[i])) mkdir(path1) img_path = os.path.join(path1, img_name) im.save(img_path) print('-----', i, '-----') def all_json_2_img(root_path, save_root_path): """ transform json files to images Args: json_path (str): the root path of 3500 json files save_path (str): the root path to save images """ usage = ['train', 'test'] for i in range(2): x = usage[i] files_path = os.path.join(root_path, x) files = os.listdir(files_path) for name in files: user_name = name.split('.')[0] json_path = os.path.join(files_path, name) save_path1 = os.path.join(save_root_path, user_name) mkdir(save_path1) save_path = os.path.join(save_path1, x) mkdir(save_path) print('=============================' + name + '=======================') json_2_img(json_path, save_path) all_json_2_img("leaf/data/femnist/3500_client_json/", "leaf/data/femnist/3500_client_img/")
运行该脚本打印如下，代表运行成功：
=============================f0644_19.json======================= ----- 0 ----- ----- 1 ----- ----- 2 ----- ......
由于有些用户文件夹下的数据集较小，若数量小于batch size，需要进行随机扩充。
可参考下面代码对整个数据集
"leaf/data/femnist/3500_client_img/"进行检查并扩充：import os import shutil from random import choice def count_dir(path): num = 0 for root, dirs, files in os.walk(path): for file in files: num += 1 return num def get_img_list(path): img_path_list = [] label_list = os.listdir(path) for i in range(len(label_list)): label = label_list[i] imgs_path = os.path.join(path, label) imgs_name = os.listdir(imgs_path) for j in range(len(imgs_name)): img_name = imgs_name[j] img_path = os.path.join(imgs_path, img_name) img_path_list.append(img_path) return img_path_list def data_aug(data_root_path, batch_size = 32): users = os.listdir(data_root_path) tags = ["train", "test"] aug_users = [] for i in range(len(users)): user = users[i] for tag in tags: data_path = os.path.join(data_root_path, user, tag) num_data = count_dir(data_path) if num_data < batch_size: aug_users.append(user + "_" + tag) print("user: ", user, " ", tag, " data number: ", num_data, " < ", batch_size, " should be aug") aug_num = batch_size - num_data img_path_list = get_img_list(data_path) for j in range(aug_num): img_path = choice(img_path_list) info = img_path.split(".") aug_img_path = info[0] + "_aug_" + str(j) + ".png" shutil.copy(img_path, aug_img_path) print("[aug", j, "]", "============= copy file:", img_path, "to ->", aug_img_path) print("the number of all aug users: " + str(len(aug_users))) print("aug user name: ", end=" ") for k in range(len(aug_users)): print(aug_users[k], end = " ") if __name__ == "__main__": data_root_path = "leaf/data/femnist/3500_client_img/" batch_size = 32 data_aug(data_root_path, batch_size)
将扩充后图片数据集转换为联邦学习框架可用的bin文件格式。
可参考下面代码：
import numpy as np import os import mindspore.dataset as ds import mindspore.dataset.vision as vision import mindspore.dataset.transforms as transforms import mindspore def mkdir(path): if not os.path.exists(path): os.mkdir(path) def count_id(path): files = os.listdir(path) ids = {} for i in files: ids[i] = int(i) return ids def create_dataset_from_folder(data_path, img_size, batch_size=32, repeat_size=1, num_parallel_workers=1, shuffle=False): """ create dataset for train or test Args: data_path: Data path batch_size: The number of data records in each group repeat_size: The number of replicated data records num_parallel_workers: The number of parallel workers """ # define dataset ids = count_id(data_path) mnist_ds = ds.ImageFolderDataset(dataset_dir=data_path, decode=False, class_indexing=ids) # define operation parameters resize_height, resize_width = img_size[0], img_size[1] # 32 transform = [ vision.Decode(True), vision.Grayscale(1), vision.Resize(size=(resize_height, resize_width)), vision.Grayscale(3), vision.ToTensor(), ] compose = transforms.Compose(transform) # apply map operations on images mnist_ds = mnist_ds.map(input_columns="label", operations=transforms.TypeCast(mindspore.int32)) mnist_ds = mnist_ds.map(input_columns="image", operations=compose) # apply DatasetOps buffer_size = 10000 if shuffle: mnist_ds = mnist_ds.shuffle(buffer_size=buffer_size) # 10000 as in LeNet train script mnist_ds = mnist_ds.batch(batch_size, drop_remainder=True) mnist_ds = mnist_ds.repeat(repeat_size) return mnist_ds def img2bin(root_path, root_save): """ transform images to bin files Args: root_path: the root path of 3500 images files root_save: the root path to save bin files """ use_list = [] train_batch_num = [] test_batch_num = [] mkdir(root_save) users = os.listdir(root_path) for user in users: use_list.append(user) user_path = os.path.join(root_path, user) train_test = os.listdir(user_path) for tag in train_test: data_path = os.path.join(user_path, tag) dataset = create_dataset_from_folder(data_path, (32, 32, 1), 32) batch_num = 0 img_list = [] label_list = [] for data in dataset.create_dict_iterator(): batch_x_tensor = data['image'] batch_y_tensor = data['label'] trans_img = np.transpose(batch_x_tensor.asnumpy(), [0, 2, 3, 1]) img_list.append(trans_img) label_list.append(batch_y_tensor.asnumpy()) batch_num += 1 if tag == "train": train_batch_num.append(batch_num) elif tag == "test": test_batch_num.append(batch_num) imgs = np.array(img_list) # (batch_num, 32,3,32,32) labels = np.array(label_list) path1 = os.path.join(root_save, user) mkdir(path1) image_path = os.path.join(path1, user + "_" + "bn_" + str(batch_num) + "_" + tag + "_data.bin") label_path = os.path.join(path1, user + "_" + "bn_" + str(batch_num) + "_" + tag + "_label.bin") imgs.tofile(image_path) labels.tofile(label_path) print("user: " + user + " " + tag + "_batch_num: " + str(batch_num)) print("total " + str(len(use_list)) + " users finished!") root_path = "leaf/data/femnist/3500_client_img/" root_save = "leaf/data/femnist/3500_clients_bin" img2bin(root_path, root_save)
运行该脚本打印如下，代表运行成功：
user: f0141_43 test_batch_num: 1 user: f0141_43 train_batch_num: 10 user: f0137_14 test_batch_num: 1 user: f0137_14 train_batch_num: 11 ...... total 3500 users finished!
生成
3500_clients_bin文件夹内共包含3500个用户文件夹，其目录结构如下：leaf/data/femnist/3500_clients_bin ├── f0000_14 # 用户编号 │ ├── f0000_14_bn_10_train_data.bin # 用户f0000_14的训练数据 （bn_后面的数字10代表batch number） │ ├── f0000_14_bn_10_train_label.bin # 用户f0000_14的训练标签 │ ├── f0000_14_bn_1_test_data.bin # 用户f0000_14的测试数据 （bn_后面的数字1代表batch number） │ └── f0000_14_bn_1_test_label.bin # 用户f0000_14的测试标签 ├── f0001_41 # 用户编号 │ ├── f0001_41_bn_11_train_data.bin # 用户f0001_41的训练数据 （bn_后面的数字11代表batch number） │ ├── f0001_41_bn_11_train_label.bin # 用户f0001_41的训练标签 │ ├── f0001_41_bn_1_test_data.bin # 用户f0001_41的测试数据 （bn_后面的数字1代表batch number） │ └── f0001_41_bn_1_test_label.bin # 用户f0001_41的测试标签 │ ... └── f4099_10 # 用户编号 ├── f4099_10_bn_4_train_data.bin # 用户f4099_10的训练数据 （bn_后面的数字4代表batch number） ├── f4099_10_bn_4_train_label.bin # 用户f4099_10的训练标签 ├── f4099_10_bn_1_test_data.bin # 用户f4099_10的测试数据 （bn_后面的数字1代表batch number） └── f4099_10_bn_1_test_label.bin # 用户f4099_10的测试标签
根据以上1～9步骤生成的3500_clients_bin文件夹可直接作为端云联邦图像分类任务的输入数据。