python如何对图片或文件的操作

import base64
from io import BytesIO
from PIL import Image

# base64 编码的图像数据（示例）
base64_data = "iVBn9DHASKJDjDsdSADSf8lgg=="


# 将 base64 编码的字符串解码为二进制数据
binary_data = base64.b64decode(base64_data)

# 将二进制数据转换为 BytesIO 对象
bytes_io = BytesIO(binary_data)

# 使用 PIL（Pillow）加载图像
image = Image.open(bytes_io)

# 保存图像
image.save("output_image.png")

print("图像保存成功")

import base64

def file_to_base64(file_path):
    with open(file_path, "rb") as file:
        # 读取文件内容
        file_data = file.read()
        # 使用base64编码
        base64_encoded = base64.b64encode(file_data)
        # 将bytes对象转换为字符串
        base64_string = base64_encoded.decode("utf-8")
        return base64_string


# 示例：将图片转换为Base64编码
image_path = "D:/output_image.png"

base64_data = file_to_base64(image_path)

# 打印Base64编码
print(base64_data)

"""
读取图片像素点矩阵, 写入到json文件
"""
from PIL import Image
import numpy as np
import json

# 打开图片
img = Image.open('D:/input_image.png')

# 获取图片大小和格式
print(img.size, img.format)

# 显示图片
# img.show()

# 获取像素数据
pixels = np.array(img)

# 将像素点转为 list 写入文件
file_object = open('D:/why.json', 'w', encoding="utf8")
json.dump(pixels.tolist(), file_object, ensure_ascii=False)

"""
读取像素点矩阵, 生成图片
"""
import json
import numpy as np
import cv2

file_object = open("D:/why.json", "r+", encoding='utf8')
file_data_str = file_object.read()
file_object.close()

matrix_data = json.loads(file_data_str)

image = np.array(matrix_data, dtype=np.uint8)
print(image.shape)

cv2.imwrite("D:/output_image2.jpg", image)

# 本地文件转二进制
def file_binary(path):
    with open(path, 'rb') as file:
        binary_data = file.read()
    return binary_data


file_path = "D:/input_image.png"
binary = file_binary(file_path)

# 本地文件转二进制
def file_binary(path):
    with open(path, 'rb') as file:
        binary_data = file.read()
    return binary_data


# 二进制写入到本地文件
def save_binary_file(path, binary_data):
    # 将二进制数据写入文件
    with open(path, "wb") as file:
        file.write(binary_data)


file_path = "D:/input_image.png"
binary = file_binary(file_path)

to_file_path = "D:/output_image.png"
save_binary_file(to_file_path, binary)

import hashlib

# 计算本地文件的 md5 值
def calculate_md5(path):
    # 打开图像文件
    with open(path, "rb") as f:
        # 读取图像数据
        binary_data = f.read()

    # 计算 MD5 值
    md5_hash = hashlib.md5(binary_data)
    md5_value = md5_hash.hexdigest()

    return md5_value


# 图像文件路径
file_path = "D:/output_image.png"

# 获取图像的 MD5 值
md5 = calculate_md5(file_path)
print(md5)

import hashlib

# 本地文件转二进制
def file_binary(path):
    with open(path, 'rb') as file:
        binary_data = file.read()
    return binary_data


# 计算二进制数据的 md5
def calculate_md5(binary_data):
    # 检查是否是 Unicode 字符串
    # (因为二进制数据除了是从文件中直接读取的, 也有可能是从数据库中获取, 比如 mongo)
    if isinstance(binary_data, str):
        # 将 Unicode 字符串编码为字节对象
        binary_data = binary_data.encode('utf-8')

    md5_hash = hashlib.md5(binary_data)
    return md5_hash.hexdigest()


file_path = "D:/input_image.png"
binary = file_binary(file_path)

# 计算 MD5 值
md5 = calculate_md5(binary)

print(md5)

certutil -hashfile test.pdf MD5

md5sum test.pdf

import urllib.request
import urllib.parse


url = "https://t7.baidu.com/it/u=1595072465,3644073269&fm=193&f=GIF"

urllib.request.urlretrieve(url, "D:/abc.jpg")

def create_folder_if_not_exists(folder_path):
    # 检查文件夹是否存在
    if not os.path.exists(folder_path):
        # 如果不存在，创建文件夹
        os.makedirs(folder_path)