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/main-gummy.py

@@ -0,0 +1,51 @@
+import sys
+
+if sys.platform == 'win32':
+    from sysaudio.win import AudioStream, mergeStreamChannels
+elif sys.platform == 'linux':
+    from sysaudio.linux import AudioStream, mergeStreamChannels
+else:
+    raise NotImplementedError(f"Unsupported platform: {sys.platform}")
+
+from audio2text.gummy import GummyTranslator
+import sys
+import argparse
+
+def convert_audio_to_text(s_lang, t_lang, audio_type):
+    sys.stdout.reconfigure(line_buffering=True) # type: ignore
+    stream = AudioStream(audio_type)
+    stream.openStream()
+
+    if t_lang == 'none':
+        gummy = GummyTranslator(stream.RATE, s_lang, None)
+    else:
+        gummy = GummyTranslator(stream.RATE, s_lang, t_lang)
+    gummy.translator.start()
+
+    while True:
+        try:
+            if not stream.stream: continue
+            data = stream.stream.read(stream.CHUNK)
+            data = mergeStreamChannels(data, stream.CHANNELS)
+            try:
+                gummy.translator.send_audio_frame(data)
+            except:
+                gummy.translator.start()
+                gummy.translator.send_audio_frame(data)
+        except KeyboardInterrupt:
+            stream.closeStream()
+            gummy.translator.stop()
+            break
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(description='Convert system audio stream to text')
+    parser.add_argument('-s', '--source_language', default='en', help='Source language code')
+    parser.add_argument('-t', '--target_language', default='zh', help='Target language code')
+    parser.add_argument('-a', '--audio_type', default='0', help='Audio stream source: 0 for output audio stream, 1 for input audio stream')
+    args = parser.parse_args()
+    convert_audio_to_text(
+        args.source_language,
+        args.target_language,
+        0 if args.audio_type == '0' else 1
+    )