diff --git a/conf/app.ini b/conf/app.ini
index 13defc9..1952951 100644
--- a/conf/app.ini
+++ b/conf/app.ini
@@ -1,7 +1,8 @@
 [server]
 port=8080
-debug=True
+debug=0
 host=0.0.0.0
+threaded=0
 
 [user]
 username=admin
diff --git a/file.py b/file.py
index a765022..cf950ab 100644
--- a/file.py
+++ b/file.py
@@ -71,22 +71,23 @@ def raedZip(bookid: str, index: int):
 def thumbnail(input,size=(400,800)):
     im = Image.open(io.BytesIO(input))
     del input
-    im = im.convert('RGB')
-    im.thumbnail(size)
-    output_io = io.BytesIO()
-    im.save(output_io,format='WEBP')
+    newimg = im.convert('RGB')
     im.close()
+    newimg.thumbnail(size)
+    output_io = io.BytesIO()
+    newimg.save(output_io,format='WEBP')
+    newimg.close()
     output_io.seek(0)
     return output_io
 
 def imageToWebP(input):
-    im = Image.open(io.BytesIO(input))
-    del input
-    im = im.convert('RGB')
-    output_io = io.BytesIO()
-    im.save(output_io,format='WEBP')
-    im.close()
-    output_io.seek(0)
+    with Image.open(io.BytesIO(input)) as img:
+        newimg = img.convert('RGB')
+        img.close()
+        output_io = io.BytesIO()
+        newimg.save(output_io,format='WEBP')
+        newimg.close()
+        output_io.seek(0)
     return output_io
     
     
diff --git a/main.py b/main.py
index c73c362..cecd6eb 100644
--- a/main.py
+++ b/main.py
@@ -24,7 +24,8 @@ app.register_blueprint(page_bp)
 if __name__ == "__main__":
     appinit()
     app.run(
-        debug=config.get("server", "debug"),
+        debug=config.getboolean("server", "debug"),
         host=config.get("server", "host"),
         port=config.get("server", "port"),
+        threaded=config.getboolean("server", "threaded"),
     )
diff --git a/web/api_Img.py b/web/api_Img.py
index fa4fe9f..dfc0cdc 100644
--- a/web/api_Img.py
+++ b/web/api_Img.py
@@ -9,7 +9,7 @@ api_Img_bp = Blueprint("api_Img_bp", __name__)
 def img(bookid, index):  # 图片接口
     if request.cookies.get("islogin") is None:
         return abort(403)
-    if db.file.searchByid(bookid) == "":
+    if len(db.file.searchByid(bookid)) == 0:
         return abort(404)
     # 设置响应类型为图片
     data, filename = file.raedZip(bookid, index)
diff --git a/web/page.py b/web/page.py
index 82043af..2e00f27 100644
--- a/web/page.py
+++ b/web/page.py
@@ -36,7 +36,7 @@ def book(bookid):  # 接口
     if request.cookies.get("islogin") is None:
         return abort(403)
     data = db.file.searchByid(bookid)
-    if data == "":
+    if len(data) == 0:
         return abort(404)
     data[0] = list(data[0])
     data[0][2] = data[0][2][0:-4] # 把文件扩展名去掉
@@ -55,7 +55,7 @@ def view(bookid):  # 接口
     if request.cookies.get("islogin") is None:
         return abort(403)
     data = db.file.searchByid(bookid)
-    if data == "":
+    if len(data) == 0:
         return abort(404)
     return render_template("view.html", id=bookid, index=range(1, data[0][3]))