diff --git a/apps/desktop/src-tauri/src/infrastructure/frame_extractor.rs b/apps/desktop/src-tauri/src/infrastructure/frame_extractor.rs
index a1dd2a6..ab88e41 100644
--- a/apps/desktop/src-tauri/src/infrastructure/frame_extractor.rs
+++ b/apps/desktop/src-tauri/src/infrastructure/frame_extractor.rs
@@ -527,8 +527,8 @@ impl FrameExtractorService {
     fn jpeg_quality_to_qscale(quality: u8) -> u8 {
         // FFmpeg qscale: 1 (最高质量) 到 31 (最低质量)
         // 质量值: 1-100
-        let clamped_quality = quality.clamp(1, 100);
-        31 - ((clamped_quality - 1) * 30 / 99)
+        let clamped_quality = quality.clamp(1, 100) as u32;
+        (31 - ((clamped_quality - 1) * 30 / 99)) as u8
     }
 
     /// 计算提取时间点