feat(util): 添加FFmpeg通用参数环境变量支持

- 通过FFMPEG_COMMON_ARGS环境变量传入通用FFmpeg参数
- 在执行FFmpeg命令时合并环境变量中的通用参数
- 保持原有FFmpeg参数传递机制不变

biz/ffmpeg.py

@@ -129,7 +129,9 @@ def check_placeholder_exist_with_count(placeholder_id, task_params, required_cou
     return False
 
 
-def start_ffmpeg_task(ffmpeg_task, max_workers=4):
+def start_ffmpeg_task(ffmpeg_task, max_workers=None):
+    if max_workers is None:
+        max_workers = int(os.environ.get("FFMPEG_MAX_WORKERS", 4))
     tracer = get_tracer(__name__)
     with tracer.start_as_current_span("start_ffmpeg_task") as span:
         sub_tasks = list(ffmpeg_task.analyze_input_render_tasks())

util/ffmpeg.py

@@ -64,7 +64,9 @@ def start_render(ffmpeg_task: FfmpegTask):
             ffmpeg_task.set_output_file(ffmpeg_task.input_file[0])
             span.set_status(Status(StatusCode.OK))
             return True
-        ffmpeg_process = subprocess.run(["ffmpeg", "-progress", "-", "-loglevel", "error", *ffmpeg_args], stderr=subprocess.PIPE, **subprocess_args(True))
+        # 通过环境变量传入通用FFmpeg参数
+        common_args = os.getenv("FFMPEG_COMMON_ARGS", "").split() if os.getenv("FFMPEG_COMMON_ARGS") else []
+        ffmpeg_process = subprocess.run(["ffmpeg", "-progress", "-", "-loglevel", "error", *common_args, *ffmpeg_args], stderr=subprocess.PIPE, **subprocess_args(True))
         span.set_attribute("ffmpeg.args", json.dumps(ffmpeg_process.args))
         logger.info(" ".join(ffmpeg_process.args))
         ffmpeg_final_out = handle_ffmpeg_output(ffmpeg_process.stdout)