fix: 修复PIP overlay顺序、音频索引、帧率统一等关键bug

apps/worker/video_processing/editing_modes.py

@@ -186,9 +186,10 @@ class EditingModeProcessor:
         return position_offsets.get(self.config.pip_position, position_offsets[PIPPosition.TOP_RIGHT])
 
     def _normalize_video(self, input_path: str, output_path: str) -> dict:
-        """标准化视频格式"""
+        """标准化视频格式：先统一帧率，再缩放/填充"""
         command = [
             self._ffmpeg_bin, "-y", "-i", input_path,
+            "-r", str(self.config.output_fps),  # 先统一帧率
             "-vf", f"scale={self.config.output_width}:{self.config.output_height}:force_original_aspect_ratio=decrease,pad={self.config.output_width}:{self.config.output_height}:(ow-iw)/2:(oh-ih)/2,setsar=1",
             "-r", str(self.config.output_fps),
             "-c:v", self.config.output_codec,
@@ -320,7 +321,7 @@ class EditingModeProcessor:
 
         command = [
             self._ffmpeg_bin, "-y", "-i", main_normalized, "-i", pip_normalized_input,
-            "-filter_complex", f"[1:v][0:v]overlay={x_offset}:{y_offset}[v]",
+            "-filter_complex", f"[0:v][1:v]overlay={x_offset}:{y_offset}[v]",
             "-map", "[v]",
             "-c:v", self.config.output_codec, "-preset", self.config.output_preset,
             "-crf", str(self.config.output_crf), "-pix_fmt", "yuv420p", output_path,
@@ -381,7 +382,7 @@ class EditingModeProcessor:
 
         command = [
             self._ffmpeg_bin, "-y", "-i", blurred_bg, "-i", audio_path,
-            "-filter_complex", "[0:v]drawbox=x=0:y=0:w=iw:h=ih:color=black@0.3:enable='between(t,0,0)'[v]",
+            "-filter_complex", "[0:v]drawbox=x=0:y=0:w=iw:h=ih:color=black@0.3:t=fill[v]",
             "-map", "[v]", "-map", "1:a",
             "-c:v", self.config.output_codec, "-preset", self.config.output_preset,
             "-crf", str(self.config.output_crf), "-pix_fmt", "yuv420p", "-shortest", output_path,
@@ -439,7 +440,7 @@ class EditingModeProcessor:
         if audio_path:
             command = [
                 self._ffmpeg_bin, "-y", "-i", bg_adjusted, "-i", voice_adjusted, "-i", audio_path,
-                "-filter_complex", f"[1:v][0:v]overlay={x_offset}:{y_offset}[v]",
+                "-filter_complex", f"[0:v][1:v]overlay={x_offset}:{y_offset}[v]",
                 "-map", "[v]", "-map", "2:a", "-shortest",
                 "-c:v", self.config.output_codec, "-preset", self.config.output_preset,
                 "-crf", str(self.config.output_crf), "-pix_fmt", "yuv420p", output_path,
@@ -447,7 +448,7 @@ class EditingModeProcessor:
         else:
             command = [
                 self._ffmpeg_bin, "-y", "-i", bg_adjusted, "-i", voice_adjusted,
-                "-filter_complex", f"[1:v][0:v]overlay={x_offset}:{y_offset}[v]",
+                "-filter_complex", f"[0:v][1:v]overlay={x_offset}:{y_offset}[v]",
                 "-map", "[v]", "-map", "1:a", "-shortest",
                 "-c:v", self.config.output_codec, "-preset", self.config.output_preset,
                 "-crf", str(self.config.output_crf), "-pix_fmt", "yuv420p", output_path,