diff --git a/Readme.md b/Readme.md
index b3f8b8c..13886ee 100644
--- a/Readme.md
+++ b/Readme.md
@@ -1,35 +1,218 @@
-# 所需环境
-python=3.10
+# Bilibili 视频下载器
 
-ffmpeg
+一个基于 bilibili-api-python 的 B 站视频下载工具，支持自动发现相关视频并批量下载。
 
+## 功能特性
 
-# 所需数据库
+- 🎥 支持 B 站视频下载
+- 🔄 自动发现并下载相关视频
+- 📝 持久化保存已下载视频记录（基于 bvid 去重）
+- 🚀 多线程下载，后台自动处理
+- 💾 自动合并音视频流
+
+## 环境要求
+
+- Python 3.10+
+- ffmpeg
+- 网络连接
+
+## 安装依赖
 
 ```bash
-mongo:可以自建也可以使用
+pip install bilibili-api-python
 ```
-[免费的云](https://cloud.mongodb.com)
 
-# 使用
+## 安装 ffmpeg
+
+### Windows
+
+#### 方法一：使用 winget（推荐）
+
+```powershell
+winget install ffmpeg
+```
+
+#### 方法二：手动安装
+
+1. 访问 [ffmpeg 官网](https://ffmpeg.org/download.html) 或 [BtbN FFmpeg Builds](https://github.com/BtbN/FFmpeg-Builds/releases)
+2. 下载 Windows 版本的 ffmpeg（选择 `ffmpeg-master-latest-win64-gpl.zip`）
+3. 解压到 `C:\ffmpeg` 目录
+4. 将 `C:\ffmpeg\bin` 添加到系统环境变量 PATH 中：
+   - 右键「此电脑」→「属性」→「高级系统设置」→「环境变量」
+   - 在「系统变量」中找到 Path，点击「编辑」
+   - 添加 `C:\ffmpeg\bin`
+   - 点击「确定」保存
+
+#### 方法三：使用 Chocolatey
+
+```powershell
+choco install ffmpeg
+```
+
+### macOS
+
+#### 使用国内 Homebrew 镜像安装（推荐）
+
+由于网络原因，建议使用国内镜像源：
+
+**1. 配置 Homebrew 国内镜像**
 
-## 先安装依赖
 ```bash
-pip install -r requerment.txt
+# 替换 Homebrew 源
+export HOMEBREW_BREW_GIT_REMOTE="https://mirrors.tuna.tsinghua.edu.cn/git/homebrew/brew.git"
+export HOMEBREW_BOTTLE_DOMAIN="https://mirrors.tuna.tsinghua.edu.cn/homebrew-bottles"
+
+# 重置 Homebrew
+git -C "$(brew --repo)" remote set-url origin https://mirrors.tuna.tsinghua.edu.cn/git/homebrew/brew.git
+git -C "$(brew --repo homebrew/core)" remote set-url origin https://mirrors.tuna.tsinghua.edu.cn/git/homebrew/homebrew-core.git
 ```
 
-## 配置数据库的地址
+**2. 安装 ffmpeg**
+
 ```bash
-MONGO_URI = "mongodb://192.168.28.9:27017/"
-```
-## 检查ffmpeg是否下载
-```
-ffmpeg --version
-# 未下载需要下载 brew install ffmpeg
+brew install ffmpeg
 ```
 
-## 将数据写入到urls.txt中
+#### 使用官方 Homebrew 安装
 
-一行一个链接
+```bash
+# 安装 Homebrew（如果未安装）
+/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
 
-## 启动脚本
\ No newline at end of file
+# 安装 ffmpeg
+brew install ffmpeg
+```
+
+### Linux
+
+#### Ubuntu/Debian
+
+```bash
+sudo apt update
+sudo apt install ffmpeg
+```
+
+#### CentOS/RHEL/Fedora
+
+**CentOS/RHEL：**
+```bash
+sudo yum install epel-release
+sudo yum install ffmpeg
+```
+
+**Fedora：**
+```bash
+sudo dnf install ffmpeg
+```
+
+#### Arch Linux
+
+```bash
+sudo pacman -S ffmpeg
+```
+
+#### 使用 Snap 安装
+
+```bash
+sudo snap install ffmpeg
+```
+
+## 使用方法
+
+### 1. 运行程序
+
+```bash
+python spider.py
+```
+
+### 2. 输入视频链接
+
+程序启动后，会显示提示符：
+
+```
+==================================================
+Bilibili Video Downloader
+==================================================
+Download worker started in background
+Enter bilibili video URLs to download
+Related videos will be automatically discovered and queued
+Type 'quit' to exit
+==================================================
+input worker started, waiting for URLs...
+Enter a bilibili URL (or 'quit' to exit):
+>
+```
+
+### 3. 输入 B 站视频链接
+
+支持的链接格式：
+- `https://www.bilibili.com/video/BV1xx411c7mD`
+- `https://b23.tv/xxxxx`
+- 直接输入 bvid：`BV1xx411c7mD`
+
+示例：
+```
+> https://www.bilibili.com/video/BV1xx411c7mD
+added to queue: BV1xx411c7mD, queue size: 1
+```
+
+### 4. 自动下载
+
+- 程序会在后台自动下载队列中的视频
+- 下载完成后会自动发现相关视频并添加到队列
+- 已下载的视频会记录在 `downloaded_bvids.txt` 文件中，避免重复下载
+
+### 5. 退出程序
+
+```
+> quit
+stopping...
+```
+
+## 文件说明
+
+```
+spider/
+├── spider.py              # 主程序
+├── downloaded_bvids.txt   # 已下载视频记录（自动生成）
+├── downloads/             # 下载目录（自动生成）
+│   ├── BV1xx411c7mD_视频标题.mp4
+│   └── ...
+├── requirements.txt       # Python 依赖
+└── README.md             # 本文件
+```
+
+## 注意事项
+
+1. **首次运行**：程序会自动查找 ffmpeg，请确保已正确安装
+2. **下载位置**：视频默认下载到 `downloads/` 目录
+3. **去重机制**：程序基于 bvid 进行去重，已下载的视频不会重复下载
+4. **网络要求**：需要稳定的网络连接，建议使用国内网络环境
+5. **存储空间**：请确保有足够的磁盘空间存储视频
+
+## 常见问题
+
+### Q: 提示 "ffmpeg not found"
+
+A: 请按照上述安装教程安装 ffmpeg，并确保添加到系统环境变量中。
+
+### Q: 下载速度慢
+
+A: 下载速度取决于网络环境和 B 站服务器，建议在网络较好的时段下载。
+
+### Q: 如何重新下载已下载的视频
+
+A: 删除 `downloaded_bvids.txt` 文件中对应的 bvid 行，或删除整个文件重新开始。
+
+### Q: 程序卡住不动
+
+A: 可能是网络问题，可以按 `Ctrl+C` 终止程序后重新运行。
+
+## 许可证
+
+MIT License
+
+## 致谢
+
+- [bilibili-api-python](https://github.com/MoyuScript/bilibili-api-python) - B 站 API 库
+- [FFmpeg](https://ffmpeg.org/) - 音视频处理工具
\ No newline at end of file
diff --git a/spider.py b/spider.py
index 42f576b..8cf6d8a 100644
--- a/spider.py
+++ b/spider.py
@@ -3,32 +3,74 @@ import re
 import subprocess
 import threading
 import time
+import shutil
 from pathlib import Path
+from collections import deque
 
 from bilibili_api import HEADERS, get_client, video  # pip install bilibili-api-python
-from pymongo import MongoClient, ReturnDocument  # pip install pymongo
 
 
-MONGO_URI = "mongodb://192.168.28.9:27017/"
-MONGO_DB_NAME = "bilibiliss"
-VIDEO_COLLECTION = "bilibili_video_pool"
-
 BASE_DIR = Path(__file__).resolve().parent
-URLS_FILE = BASE_DIR / "urls.txt"
 OUTPUT_DIR = BASE_DIR / "downloads"
-FFMPEG_PATH = "ffmpeg"
+DOWNLOADED_BVID_FILE = BASE_DIR / "downloaded_bvids.txt"  # 已下载 bvid 记录文件
+FFMPEG_PATH = None  # Will be set by find_ffmpeg()
 POLL_SECONDS = 2
 FETCH_RELATED_LIMIT = 20
 
-STATUS_INIT = "init"
-STATUS_FETCHING = "fetching"
-STATUS_READY = "ready"
-STATUS_DOWNLOADING = "downloading"
-STATUS_DONE = "done"
-STATUS_ERROR = "error"
 
-client = MongoClient(MONGO_URI)
-collection = client[MONGO_DB_NAME][VIDEO_COLLECTION]
+def find_ffmpeg():
+    """查找 ffmpeg 可执行文件的路径"""
+    # 首先尝试在系统 PATH 中查找
+    ffmpeg_path = shutil.which("ffmpeg")
+    if ffmpeg_path:
+        return ffmpeg_path
+    
+    # Windows 常见的 ffmpeg 安装位置
+    common_paths = [
+        r"C:\ffmpeg\bin\ffmpeg.exe",
+        r"C:\Program Files\ffmpeg\bin\ffmpeg.exe",
+        r"C:\Program Files (x86)\ffmpeg\bin\ffmpeg.exe",
+        Path.home() / "ffmpeg" / "bin" / "ffmpeg.exe",
+        Path.home() / "Downloads" / "ffmpeg" / "bin" / "ffmpeg.exe",
+        BASE_DIR / "ffmpeg" / "bin" / "ffmpeg.exe",
+        BASE_DIR / "ffmpeg.exe",
+    ]
+    
+    for path in common_paths:
+        if Path(path).exists():
+            return str(path)
+    
+    return None
+
+# 使用线程安全的队列替代数据库
+video_queue = deque()  # 待下载的视频队列
+downloaded_set = set()  # 已下载的视频集合，防止重复
+queue_lock = threading.Lock()
+
+
+def load_downloaded_bvids():
+    """从文件加载已下载的 bvid 列表"""
+    global downloaded_set
+    if DOWNLOADED_BVID_FILE.exists():
+        try:
+            with open(DOWNLOADED_BVID_FILE, "r", encoding="utf-8") as f:
+                downloaded_set = set(line.strip() for line in f if line.strip())
+            print(f"loaded {len(downloaded_set)} downloaded bvids from file")
+        except Exception as e:
+            print(f"failed to load downloaded bvids: {e}")
+            downloaded_set = set()
+    else:
+        print("no downloaded bvids file found, starting fresh")
+        downloaded_set = set()
+
+
+def save_downloaded_bvid(bvid: str):
+    """将 bvid 追加保存到文件"""
+    try:
+        with open(DOWNLOADED_BVID_FILE, "a", encoding="utf-8") as f:
+            f.write(bvid + "\n")
+    except Exception as e:
+        print(f"failed to save bvid {bvid}: {e}")
 
 
 def get_bvid_from_url(url: str) -> str:
@@ -56,85 +98,28 @@ def get_output_path(file_name: str) -> Path:
     return OUTPUT_DIR / file_name
 
 
-def ensure_indexes():
-    collection.create_index("bvid", unique=True)
-    collection.create_index("status")
+def add_to_queue(bvid: str, source_url: str = ""):
+    """添加视频到下载队列"""
+    with queue_lock:
+        if bvid not in downloaded_set and bvid not in [item["bvid"] for item in video_queue]:
+            video_queue.append({
+                "bvid": bvid,
+                "source_url": source_url or f"https://www.bilibili.com/video/{bvid}",
+                "added_at": time.time()
+            })
+            print(f"added to queue: {bvid}, queue size: {len(video_queue)}")
+            return True
+        else:
+            print(f"skipped duplicate: {bvid}")
+            return False
 
 
-def reset_in_progress_docs():
-    fetch_reset = collection.update_many(
-        {"status": STATUS_FETCHING},
-        {"$set": {"status": STATUS_INIT, "updated_at": time.time()}},
-    )
-    download_reset = collection.update_many(
-        {"status": STATUS_DOWNLOADING},
-        {"$set": {"status": STATUS_READY, "updated_at": time.time()}},
-    )
-    print(
-        f"reset in-progress docs: fetching={fetch_reset.modified_count}, "
-        f"downloading={download_reset.modified_count}"
-    )
-
-
-def seed_from_urls_file():
-    if not URLS_FILE.exists():
-        print(f"seed skipped, file not found: {URLS_FILE}")
-        return
-
-    inserted = 0
-    skipped = 0
-    with open(URLS_FILE, "r", encoding="utf-8") as file_obj:
-        for raw_line in file_obj:
-            url = raw_line.strip()
-            if not url:
-                continue
-            try:
-                bvid = get_bvid_from_url(url)
-            except ValueError:
-                skipped += 1
-                print(f"seed skipped, invalid url: {url}")
-                continue
-
-            result = collection.update_one(
-                {"bvid": bvid},
-                {
-                    "$setOnInsert": {
-                        "bvid": bvid,
-                        "source_url": url,
-                        "video_url": f"https://www.bilibili.com/video/{bvid}",
-                        "title": "",
-                        "download_file_name": f"{bvid}.mp4",
-                        "status": STATUS_INIT,
-                        "related_fetched": False,
-                        "downloaded": False,
-                        "created_at": time.time(),
-                    }
-                },
-                upsert=True,
-            )
-            if result.upserted_id is not None:
-                inserted += 1
-            else:
-                skipped += 1
-                print(f"seed duplicate skipped: {bvid}")
-
-    print(f"seed complete, inserted={inserted}, skipped={skipped}")
-
-
-def claim_fetch_doc():
-    return collection.find_one_and_update(
-        {"status": STATUS_INIT, "related_fetched": False},
-        {"$set": {"status": STATUS_FETCHING, "fetch_started_at": time.time()}},
-        return_document=ReturnDocument.AFTER,
-    )
-
-
-def claim_download_doc():
-    return collection.find_one_and_update(
-        {"status": STATUS_READY, "downloaded": False},
-        {"$set": {"status": STATUS_DOWNLOADING, "download_started_at": time.time()}},
-        return_document=ReturnDocument.AFTER,
-    )
+def get_from_queue():
+    """从队列获取一个待下载的视频"""
+    with queue_lock:
+        if video_queue:
+            return video_queue.popleft()
+        return None
 
 
 async def fetch_video_info_and_related(bvid: str):
@@ -145,39 +130,19 @@ async def fetch_video_info_and_related(bvid: str):
 
 
 def save_related_bvids(parent_bvid: str, related_items):
+    """将相关视频添加到队列"""
     inserted = 0
     skipped = 0
     for item in related_items[:FETCH_RELATED_LIMIT]:
         related_bvid = item.get("bvid")
         if not related_bvid:
             continue
-
-        result = collection.update_one(
-            {"bvid": related_bvid},
-            {
-                "$setOnInsert": {
-                    "bvid": related_bvid,
-                    "source_url": f"https://www.bilibili.com/video/{related_bvid}",
-                    "video_url": f"https://www.bilibili.com/video/{related_bvid}",
-                    "title": item.get("title", ""),
-                    "download_file_name": build_output_file_name(
-                        related_bvid, item.get("title", "")
-                    ),
-                    "status": STATUS_INIT,
-                    "related_fetched": False,
-                    "downloaded": False,
-                    "parent_bvid": parent_bvid,
-                    "created_at": time.time(),
-                }
-            },
-            upsert=True,
-        )
-        if result.upserted_id is not None:
+        
+        if add_to_queue(related_bvid, f"https://www.bilibili.com/video/{related_bvid}"):
             inserted += 1
-            print(f"related inserted: {related_bvid}")
         else:
             skipped += 1
-            print(f"related duplicate skipped: {related_bvid}")
+    
     return inserted, skipped
 
 
@@ -196,6 +161,8 @@ async def download_stream(url: str, output_path: Path, intro: str):
 
 
 def merge_media(video_path: Path, audio_path: Path, output_path: Path):
+    if not FFMPEG_PATH:
+        raise RuntimeError("ffmpeg not found. Please install ffmpeg and add it to PATH.")
     subprocess.run(
         [
             FFMPEG_PATH,
@@ -215,6 +182,8 @@ def merge_media(video_path: Path, audio_path: Path, output_path: Path):
 
 
 def convert_flv_to_mp4(source_path: Path, output_path: Path):
+    if not FFMPEG_PATH:
+        raise RuntimeError("ffmpeg not found. Please install ffmpeg and add it to PATH.")
     subprocess.run(
         [FFMPEG_PATH, "-y", "-i", str(source_path), str(output_path)],
         check=True,
@@ -248,129 +217,121 @@ async def download_video_file(bvid: str, output_file_name: str):
     return final_path
 
 
-def mark_doc_downloaded(doc, final_path: Path):
-    collection.update_one(
-        {"_id": doc["_id"]},
-        {
-            "$set": {
-                "status": STATUS_DONE,
-                "downloaded": True,
-                "file_path": str(final_path),
-                "updated_at": time.time(),
-            }
-        },
-    )
-
-
-def process_fetch_doc(doc):
-    bvid = doc["bvid"]
+def process_download(bvid: str):
+    """处理单个视频的下载"""
     try:
+        # 获取视频信息
         info, related_items = asyncio.run(fetch_video_info_and_related(bvid))
-        title = info.get("title", "")
+        title = info.get("title", bvid)
         file_name = build_output_file_name(bvid, title)
-        inserted, skipped = save_related_bvids(bvid, related_items)
-        collection.update_one(
-            {"_id": doc["_id"]},
-            {
-                "$set": {
-                    "title": title,
-                    "aid": info.get("aid"),
-                    "cid": info.get("cid"),
-                    "owner_name": (info.get("owner") or {}).get("name", ""),
-                    "video_url": f"https://www.bilibili.com/video/{bvid}",
-                    "download_file_name": file_name,
-                    "related_fetched": True,
-                    "status": STATUS_READY,
-                    "related_inserted_count": inserted,
-                    "related_skipped_count": skipped,
-                    "updated_at": time.time(),
-                }
-            },
-        )
-        print(f"fetch done: {bvid}, related_inserted={inserted}, related_skipped={skipped}")
-    except Exception as exc:
-        collection.update_one(
-            {"_id": doc["_id"]},
-            {
-                "$set": {
-                    "status": STATUS_ERROR,
-                    "fetch_error": str(exc),
-                    "updated_at": time.time(),
-                }
-            },
-        )
-        print(f"fetch failed: {bvid}, error={exc}")
-
-
-def process_download_doc(doc):
-    bvid = doc["bvid"]
-    file_name = doc.get("download_file_name") or f"{bvid}.mp4"
-    final_path = get_output_path(file_name)
-
-    if doc.get("downloaded") and final_path.exists():
-        print(f"download already marked and file exists, skipped: {bvid}")
-        return
-
-    if final_path.exists():
-        mark_doc_downloaded(doc, final_path)
-        print(f"download file already exists, skipped: {bvid} -> {final_path}")
-        return
-
-    try:
+        
+        print(f"fetching info done: {bvid}, title: {title}")
+        
+        # 检查文件是否已存在
+        final_path = get_output_path(file_name)
+        if final_path.exists():
+            print(f"file already exists, skipped: {bvid} -> {final_path}")
+            with queue_lock:
+                downloaded_set.add(bvid)
+            return
+        
+        # 下载视频
         final_path = asyncio.run(download_video_file(bvid, file_name))
-        mark_doc_downloaded(doc, final_path)
         print(f"download done: {bvid} -> {final_path}")
+        
+        # 标记为已下载并保存到文件
+        with queue_lock:
+            downloaded_set.add(bvid)
+        save_downloaded_bvid(bvid)
+        
+        # 添加相关视频到队列
+        inserted, skipped = save_related_bvids(bvid, related_items)
+        print(f"related videos: inserted={inserted}, skipped={skipped}")
+        
     except Exception as exc:
-        collection.update_one(
-            {"_id": doc["_id"]},
-            {
-                "$set": {
-                    "status": STATUS_READY,
-                    "download_error": str(exc),
-                    "updated_at": time.time(),
-                }
-            },
-        )
         print(f"download failed: {bvid}, error={exc}")
 
 
-def fetch_worker():
-    while True:
-        doc = claim_fetch_doc()
-        if not doc:
-            time.sleep(POLL_SECONDS)
-            continue
-        process_fetch_doc(doc)
-
-
 def download_worker():
+    """下载工作线程：从队列中取出视频并下载"""
+    print("download worker started")
     while True:
-        doc = claim_download_doc()
-        if not doc:
+        item = get_from_queue()
+        if not item:
             time.sleep(POLL_SECONDS)
             continue
-        process_download_doc(doc)
+        
+        bvid = item["bvid"]
+        print(f"processing: {bvid}")
+        process_download(bvid)
+
+
+def input_worker():
+    """输入工作线程：接收用户输入的链接"""
+    print("input worker started, waiting for URLs...")
+    print("Enter a bilibili URL (or 'quit' to exit):")
+    
+    while True:
+        try:
+            url = input("> ").strip()
+            if url.lower() == 'quit':
+                print("stopping...")
+                break
+            
+            if not url:
+                continue
+            
+            try:
+                bvid = get_bvid_from_url(url)
+                add_to_queue(bvid, url)
+            except ValueError as e:
+                print(f"invalid url: {e}")
+                print("please enter a valid bilibili video URL")
+                
+        except EOFError:
+            break
+        except KeyboardInterrupt:
+            break
 
 
 def main():
-    ensure_indexes()
-    reset_in_progress_docs()
-    seed_from_urls_file()
-
-    fetch_thread = threading.Thread(target=fetch_worker, daemon=True, name="fetch-worker")
-    download_thread = threading.Thread(
-        target=download_worker, daemon=True, name="download-worker"
-    )
-    fetch_thread.start()
+    global FFMPEG_PATH
+    
+    # 查找 ffmpeg
+    FFMPEG_PATH = find_ffmpeg()
+    if not FFMPEG_PATH:
+        print("=" * 50)
+        print("ERROR: ffmpeg not found!")
+        print("=" * 50)
+        print("Please install ffmpeg and add it to your system PATH.")
+        print("Download from: https://ffmpeg.org/download.html")
+        print("Or place ffmpeg.exe in one of these locations:")
+        print("  - C:\\ffmpeg\\bin\\")
+        print("  - Current directory")
+        print("=" * 50)
+        return
+    
+    print(f"ffmpeg found at: {FFMPEG_PATH}")
+    
+    # 加载已下载的 bvid 列表
+    load_downloaded_bvids()
+    
+    # 启动下载工作线程
+    download_thread = threading.Thread(target=download_worker, daemon=True, name="download-worker")
     download_thread.start()
-
-    print("workers started: fetch-worker, download-worker")
-    try:
-        while True:
-            time.sleep(1)
-    except KeyboardInterrupt:
-        print("stopping...")
+    
+    print("=" * 50)
+    print("Bilibili Video Downloader")
+    print("=" * 50)
+    print("Download worker started in background")
+    print("Enter bilibili video URLs to download")
+    print("Related videos will be automatically discovered and queued")
+    print("Type 'quit' to exit")
+    print("=" * 50)
+    
+    # 主线程处理用户输入
+    input_worker()
 
 
 if __name__ == "__main__":
-    main()
+    main()
\ No newline at end of file