refactor: adjust rendering logic (#253)

Author: timerring

src/burn/render_command.py

@@ -14,49 +14,61 @@ def render_command(in_video_path, out_video_path, in_subtitle_font_size, in_subt
         in_subtitle_margin_v: str, the bottom margin of subtitles
     """
     in_ass_path = in_video_path[:-4] + '.ass'
+    if not os.path.isfile(in_ass_path):
+        scan_log.warning("Cannot find danmaku file, return directly")
+        subprocess.run(['mv', in_video_path, out_video_path], stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
+        return
+
     in_srt_path = in_video_path[:-4] + '.srt'
-    
-    if GPU_EXIST and os.path.isfile(in_srt_path):
-        if os.path.isfile(in_ass_path):
-            scan_log.info("Current Mode: GPU with danmaku")
-            command = [
+    if os.path.isfile(in_srt_path):
+        if GPU_EXIST:
+            scan_log.info("Current Mode: GPU with subtitles")
+            gpu_srt_ass_command = [
                 'ffmpeg', '-y', '-hwaccel', 'cuda', '-c:v', 'h264_cuvid', '-i', in_video_path,
                 '-c:v', 'h264_nvenc', '-vf', f"subtitles={in_srt_path}:force_style='Fontsize={in_subtitle_font_size},MarginV={in_subtitle_margin_v}',subtitles={in_ass_path}", out_video_path
             ]
             try:
-                result = subprocess.run(command, check=True, capture_output=True, text=True)
+                result = subprocess.run(gpu_srt_ass_command, check=True, capture_output=True, text=True)
                 scan_log.debug(f"FFmpeg output: {result.stdout}")
                 if result.stderr:
                     scan_log.debug(f"FFmpeg debug: {result.stderr}")
             except subprocess.CalledProcessError as e:
                 scan_log.error(f"Error: {e.stderr}")
-            
         else:
-            scan_log.info("Current Mode: GPU without danmaku")
-            command_no_danmaku = [
-                'ffmpeg', '-y', '-hwaccel', 'cuda', '-c:v', 'h264_cuvid', '-i', in_video_path,
-                '-c:v', 'h264_nvenc', '-vf', f"subtitles={in_srt_path}:force_style='Fontsize={in_subtitle_font_size},MarginV={in_subtitle_margin_v}'", out_video_path
+            scan_log.info("Current Mode: CPU with subtitles")
+            cpu_srt_ass_command = [
+                'ffmpeg', '-y', '-i', in_video_path, '-vf', f"subtitles={in_srt_path}:force_style='Fontsize={in_subtitle_font_size},MarginV={in_subtitle_margin_v}',subtitles={in_ass_path}", '-preset', 'ultrafast', out_video_path
             ]
             try:
-                result = subprocess.run(command_no_danmaku, check=True, capture_output=True, text=True)
+                result = subprocess.run(cpu_srt_ass_command, check=True, capture_output=True, text=True)
                 scan_log.debug(f"FFmpeg output: {result.stdout}")
                 if result.stderr:
                     scan_log.debug(f"FFmpeg debug: {result.stderr}")
             except subprocess.CalledProcessError as e:
                 scan_log.error(f"Error: {e.stderr}")
     else:
-        if os.path.isfile(in_ass_path):
-            scan_log.info("Current Mode: CPU with danmaku")
-            command_without_gpu = [
-                'ffmpeg', '-y', '-i', in_video_path, '-vf', f'ass={in_ass_path}', '-preset', 'ultrafast', out_video_path
+        if GPU_EXIST:
+            scan_log.info("Current Mode: GPU without subtitles")
+            gpu_ass_command = [
+                'ffmpeg', '-y', '-hwaccel', 'cuda', '-c:v', 'h264_cuvid', '-i', in_video_path,
+                '-c:v', 'h264_nvenc', '-vf', f"ass={in_ass_path}", out_video_path
             ]
             try:
-                result = subprocess.run(command_without_gpu, check=True, capture_output=True, text=True)
+                result = subprocess.run(gpu_ass_command, check=True, capture_output=True, text=True)
                 scan_log.debug(f"FFmpeg output: {result.stdout}")
                 if result.stderr:
                     scan_log.debug(f"FFmpeg debug: {result.stderr}")
             except subprocess.CalledProcessError as e:
                 scan_log.error(f"Error: {e.stderr}")
         else:
-            scan_log.info("Current Mode: CPU without danmaku")
-            subprocess.run(['mv', in_video_path, out_video_path], stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
+            scan_log.info("Current Mode: CPU without subtitles")
+            cpu_ass_command = [
+                'ffmpeg', '-y', '-i', in_video_path, '-vf', f"ass={in_ass_path}", '-preset', 'ultrafast', out_video_path
+            ]
+            try:
+                result = subprocess.run(cpu_ass_command, check=True, capture_output=True, text=True)
+                scan_log.debug(f"FFmpeg output: {result.stdout}")
+                if result.stderr:
+                    scan_log.debug(f"FFmpeg debug: {result.stderr}")
+            except subprocess.CalledProcessError as e:
+                scan_log.error(f"Error: {e.stderr}")