python-3.x - 批量读取Cifar10数据集

Question

我正在尝试读取 CIFAR10 数据集，从 https://www.cs.toronto.edu/~kriz/cifar.html 中批量给出>。我正在尝试使用 pickle 将其放入数据框中并读取其中的“数据”部分。但我收到此错误。

KeyError                                  Traceback (most recent call last)
<ipython-input-24-8758b7a31925> in <module>()
----> 1 unpickle('datasets/cifar-10-batches-py/test_batch')

<ipython-input-23-04002b89d842> in unpickle(file)
      3     fo = open(file, 'rb')
      4     dict = pickle.load(fo, encoding ='bytes')
----> 5     X = dict['data']
      6     fo.close()
      7     return dict

key 错误:“数据”。

我正在使用 ipython，这是我的代码:

def unpickle(file):

 fo = open(file, 'rb')
 dict = pickle.load(fo, encoding ='bytes')
 X = dict['data']
 fo.close()
 return dict

unpickle('datasets/cifar-10-batches-py/test_batch')

Answer 1

您可以通过下面给出的代码读取 cifar 10 数据集，只需确保您提供的是放置批处理的写入目录

import tensorflow as tf
import pandas as pd
import numpy as np
import math
import timeit
import matplotlib.pyplot as plt
from six.moves import cPickle as pickle
import os
import platform
from subprocess import check_output
classes = ('plane', 'car', 'bird', 'cat',
           'deer', 'dog', 'frog', 'horse', 'ship', 'truck')

%matplotlib inline


img_rows, img_cols = 32, 32
input_shape = (img_rows, img_cols, 3)
def load_pickle(f):
    version = platform.python_version_tuple()
    if version[0] == '2':
        return  pickle.load(f)
    elif version[0] == '3':
        return  pickle.load(f, encoding='latin1')
    raise ValueError("invalid python version: {}".format(version))

def load_CIFAR_batch(filename):
    """ load single batch of cifar """
    with open(filename, 'rb') as f:
        datadict = load_pickle(f)
        X = datadict['data']
        Y = datadict['labels']
        X = X.reshape(10000,3072)
        Y = np.array(Y)
        return X, Y

def load_CIFAR10(ROOT):
    """ load all of cifar """
    xs = []
    ys = []
    for b in range(1,6):
        f = os.path.join(ROOT, 'data_batch_%d' % (b, ))
        X, Y = load_CIFAR_batch(f)
        xs.append(X)
        ys.append(Y)
    Xtr = np.concatenate(xs)
    Ytr = np.concatenate(ys)
    del X, Y
    Xte, Yte = load_CIFAR_batch(os.path.join(ROOT, 'test_batch'))
    return Xtr, Ytr, Xte, Yte
def get_CIFAR10_data(num_training=49000, num_validation=1000, num_test=10000):
    # Load the raw CIFAR-10 data
    cifar10_dir = '../input/cifar-10-batches-py/'
    X_train, y_train, X_test, y_test = load_CIFAR10(cifar10_dir)

    # Subsample the data
    mask = range(num_training, num_training + num_validation)
    X_val = X_train[mask]
    y_val = y_train[mask]
    mask = range(num_training)
    X_train = X_train[mask]
    y_train = y_train[mask]
    mask = range(num_test)
    X_test = X_test[mask]
    y_test = y_test[mask]

    x_train = X_train.astype('float32')
    x_test = X_test.astype('float32')

    x_train /= 255
    x_test /= 255

    return x_train, y_train, X_val, y_val, x_test, y_test


# Invoke the above function to get our data.
x_train, y_train, x_val, y_val, x_test, y_test = get_CIFAR10_data()


print('Train data shape: ', x_train.shape)
print('Train labels shape: ', y_train.shape)
print('Validation data shape: ', x_val.shape)
print('Validation labels shape: ', y_val.shape)
print('Test data shape: ', x_test.shape)
print('Test labels shape: ', y_test.shape)