diff --git a/handlers/render_video.py b/handlers/render_video.py
index 48d19cd..1fe4cd3 100644
--- a/handlers/render_video.py
+++ b/handlers/render_video.py
@@ -547,15 +547,16 @@ class RenderSegmentVideoHandler(BaseHandler):
                 if start_sec <= 0 or duration_sec <= 0:
                     continue
 
-                # cameraShot 实现：
+                # cameraShot 实现（定格效果）：
                 # 1. fps + split 分割
-                # 2. 第一路：trim(0, start+duration) + freezeframes
+                # 2. 第一路：trim(0, start) + tpad冻结duration秒
                 # 3. 第二路：trim(start, end)
                 # 4. concat 拼接
 
-                start_frame = start_sec * fps
                 split_out_a = f'[eff{effect_idx}_a]'
                 split_out_b = f'[eff{effect_idx}_b]'
+                frozen_out = f'[eff{effect_idx}_frozen]'
+                rest_out = f'[eff{effect_idx}_rest]'
                 effect_output = f'[v_eff{effect_idx}]'
 
                 # fps + split
@@ -563,24 +564,21 @@ class RenderSegmentVideoHandler(BaseHandler):
                     f"{current_output}fps=fps={fps},split{split_out_a}{split_out_b}"
                 )
 
-                # 第一路：trim + freezeframes（在 start 帧处冻结 duration 秒）
-                # freezeframes: 从 first 帧开始，用 replace 帧替换后续帧
-                # 这样实现定格效果：在 start_frame 位置冻结
+                # 第一路：trim(0, start) + tpad冻结
+                # tpad=stop_mode=clone 将最后一帧冻结指定时长
                 filter_parts.append(
-                    f"{split_out_a}trim=start=0:end={start_sec + duration_sec},"
-                    f"setpts=PTS-STARTPTS,"
-                    f"freezeframes=first={start_frame}:last={start_frame + duration_sec * fps - 1}:replace={start_frame}"
-                    f"{split_out_a}"
+                    f"{split_out_a}trim=start=0:end={start_sec},setpts=PTS-STARTPTS,"
+                    f"tpad=stop_mode=clone:stop_duration={duration_sec}{frozen_out}"
                 )
 
                 # 第二路：trim 从 start 开始
                 filter_parts.append(
-                    f"{split_out_b}trim=start={start_sec},setpts=PTS-STARTPTS{split_out_b}"
+                    f"{split_out_b}trim=start={start_sec},setpts=PTS-STARTPTS{rest_out}"
                 )
 
                 # concat 拼接
                 filter_parts.append(
-                    f"{split_out_a}{split_out_b}concat=n=2:v=1:a=0{effect_output}"
+                    f"{frozen_out}{rest_out}concat=n=2:v=1:a=0{effect_output}"
                 )
 
                 current_output = effect_output