如何从sqlite读取blob数据并显示它

import sqlite3
import base64

def read_blob_data(database, table, column, id):
    # 连接到SQLite数据库
    conn = sqlite3.connect(database)
    cursor = conn.cursor()

    try:
        # SQL查询，获取BLOB数据
        query = f"SELECT {column} FROM {table} WHERE id=?"
        cursor.execute(query, (id,))

        # 读取BLOB数据
        result = cursor.fetchone()

        if result:
            # 将BLOB数据解码为字节串
            blob_data = result[0]
            img_data = base64.b64encode(blob_data)

            # 将字节串转换为ASCII字符
            img_str = img_data.decode('ascii')

            # 返回BLOB数据
            return img_str
        else:
            print("No data found for id =", id)
            return None
    except Exception as e:
        print("Error reading BLOB data:", e)
    finally:
        if conn:
            conn.close()

# 使用以下代码从SQLite数据库读取并显示BLOB数据
if __name__ == "__main__":
    database = "your_database.db"
    table = "your_table"
    column = "your_blob_column"
    record_id = 1

    blob_data = read_blob_data(database, table, column, record_id)

    if blob_data:
        # 在此处处理BLOB数据，例如将其显示为图像或下载为文件
        with open("output_image.png", "wb") as f:
            f.write(base64.b64decode(blob_data))