refactor(caption): 重构字幕引擎结构、修复字幕引擎空置报错 (#2)

- 修复gummy字幕引擎长时间空置报错的问题
- 将 python-subprocess 文件夹重命名为 caption-engine
- 删除未使用的 prototype 代码

caption-engine/audio2text/gummy.py

@@ -0,0 +1,82 @@
+from dashscope.audio.asr import (
+    TranslationRecognizerCallback,
+    TranscriptionResult,
+    TranslationResult,
+    TranslationRecognizerRealtime
+)
+from datetime import datetime
+import json
+import sys
+
+class Callback(TranslationRecognizerCallback):
+    """
+    语音大模型流式传输回调对象
+    """
+    def __init__(self):
+        super().__init__()
+        self.usage = 0
+        self.cur_id = -1
+        self.time_str = ''
+
+    def on_open(self) -> None:
+        # print("on_open")
+        pass
+
+    def on_close(self) -> None:
+        # print("on_close")
+        pass
+
+    def on_event(
+        self,
+        request_id,
+        transcription_result: TranscriptionResult,
+        translation_result: TranslationResult,
+        usage
+    ) -> None:
+        caption = {}
+        if transcription_result is not None:
+            caption['index'] = transcription_result.sentence_id
+            caption['text'] = transcription_result.text
+            if caption['index'] != self.cur_id:
+                self.cur_id = caption['index']
+                cur_time = datetime.now().strftime('%H:%M:%S')
+                caption['time_s'] = cur_time
+                self.time_str = cur_time
+            else:
+                caption['time_s'] = self.time_str
+            caption['time_t'] = datetime.now().strftime('%H:%M:%S')
+            caption['translation'] = ""
+
+        if translation_result is not None:
+            lang = translation_result.get_language_list()[0]
+            caption['translation'] = translation_result.get_translation(lang).text
+
+        if usage:
+            self.usage += usage['duration']
+
+        # print(caption)
+        self.send_to_node(caption)
+
+    def send_to_node(self, data):
+        """
+        将数据发送到 Node.js 进程
+        """
+        try:
+            json_data = json.dumps(data) + '\n'
+            sys.stdout.write(json_data)
+            sys.stdout.flush()
+        except Exception as e:
+            print(f"Error sending data to Node.js: {e}", file=sys.stderr)
+
+class GummyTranslator:
+    def __init__(self, rate, source, target):
+        self.translator = TranslationRecognizerRealtime(
+            model = "gummy-realtime-v1",
+            format = "pcm",
+            sample_rate = rate,
+            transcription_enabled = True,
+            translation_enabled = (target is not None),
+            source_language = source,
+            translation_target_languages = [target],
+            callback = Callback()
+        )