如何用python解析mnist图片

依赖PIL库
直接上源码， 在同目录下 建一个空的文件夹 命名为test，下载好数据集解压。 运行即可。
from PIL import Image
import struct
def read_image(filename):
    f = open(filename, 'rb')
    index = 0
    buf = f.read()
    f.close()
    magic, images, rows, columns = struct.unpack_from('>IIII', buf, index)
    index += struct.calcsize('>IIII')
    for i in range(images):
        # for i in xrange(2000):
        image = Image.new('L', (columns, rows))

        for x in range(rows):
            for y in range(columns):
                image.putpixel((y, x), int(struct.unpack_from('>B', buf, index)[0]))
                index += struct.calcsize('>B')

        print ('save ' + str(i) + 'image')
        image.save('test/' + str(i) + '.png')

def read_label(filename, saveFilename):
    f = open(filename, 'rb')
    index = 0
    buf = f.read()
    f.close()
    magic, labels = struct.unpack_from('>II', buf, index)
    index += struct.calcsize('>II')
    labelArr = [0] * labels
    # labelArr = [0] * 2000

    for x in range(labels):
        # for x in xrange(2000):
        labelArr[x] = int(struct.unpack_from('>B', buf, index)[0])
        index += struct.calcsize('>B')

    save = open(saveFilename, 'w')

    save.write(','.join(map(lambda x: str(x), labelArr)))
    save.write('\n')

    save.close()
    print ('save labels success')


if __name__ == '__main__':
    read_image('t10k-images.idx3-ubyte')
    read_label('t10k-labels.idx1-ubyte', 'test/label.txt')

转自 https://blog.youkuaiyun.com/u014046170/article/details/47445919