2020DDCTF WP

import hashlib
import hmac
import base64

secret = 'DDCTFWithYou'     #sha1=fbf2c653e6a38b5051f652bbb665ec15b4f8a180
data = "'DDCTF'|1599205604" 

sha256_computed = hashlib.sha256(data.encode("utf-8")).hexdigest()
hmac_computed = hmac.new(key=secret.encode('utf-8'),msg=sha256_computed.encode('utf-8'),digestmod=hashlib.sha1).hexdigest()
base64_computed = base64.b64encode(bytes(sha256_computed,"utf-8"))
print(base64_computed)
print(b"m/4VP+aX5JdEY3/Iq1SYYcpKj7bRLp96Q9Xy4nCBS7M=")

import PIL.Image as Image
import os
 
IMAGES_PATH = './'  # 图片集地址
IMAGES_FORMAT = ['.png']  # 图片格式
IMAGE_SIZE = 256  # 每张小图片的大小
IMAGE_ROW = 11  # 图片间隔，也就是合并成一张图后，一共有几行
IMAGE_COLUMN = 21  # 图片间隔，也就是合并成一张图后，一共有几列
IMAGE_SAVE_PATH = '../final.png'  # 图片转换后的地址
 
# 获取图片集地址下的所有图片名称

image_names = [name for name in os.listdir(IMAGES_PATH) for item in IMAGES_FORMAT if
               os.path.splitext(name)[1] == item]

def sort_file_by_time(file_path):
    files = os.listdir(file_path)
    if not files:
        return
    else:
        files = sorted(files, key=lambda x: os.path.getmtime(os.path.join(file_path, x)))#格式解释:对files进行排序.x是files的元素,:后面的是排序的依据.   x只是文件名,所以要带上join.
        return files
image_names = sort_file_by_time(IMAGES_PATH)
print(image_names)


# 简单的对于参数的设定和实际图片集的大小进行数量判断
if len(image_names) < IMAGE_ROW * IMAGE_COLUMN:
    raise ValueError("合成图片的参数和要求的数量不能匹配！")

# 定义图像拼接函数
def image_compose():
    to_image = Image.new('RGB', (IMAGE_COLUMN * IMAGE_SIZE, IMAGE_ROW * IMAGE_SIZE)) #创建一个新图
    # 循环遍历，把每张图片按顺序粘贴到对应位置上
    for y in range(1, IMAGE_ROW + 1):
        for x in range(1, IMAGE_COLUMN + 1):
            from_image = Image.open(IMAGES_PATH + image_names[IMAGE_COLUMN * (y - 1) + x - 1]).resize(
                (IMAGE_SIZE, IMAGE_SIZE),Image.ANTIALIAS)
            to_image.paste(from_image, ((x - 1) * IMAGE_SIZE, (y - 1) * IMAGE_SIZE))
    return to_image.save(IMAGE_SAVE_PATH) # 保存新图
image_compose() #调用函数