perf: video tts mix add writer buffer

src/tts/provider/volcengine/tts-mix.ts

@@ -406,12 +406,14 @@ type TTSWriteType = {
   data?: Buffer;
   isBegin?: boolean;
   isEnd?: boolean;
+  index?: number;
 };
 
 export class TtsMix {
   appId: string;
   token: string;
   emitter: EventEmitter;
+
   constructor(appId: string, token: string) {
     this.appId = appId;
     this.token = token;
@@ -427,10 +429,53 @@ export class TtsMix {
   async getVoiceDemo(speaker: string, text: string, outputPath: string): Promise<void> {
     return runDemo(this.appId, this.token, speaker, text, outputPath, this.emitter);
   }
+  /**
+   * 写入文件的时候同步的流监听
+   * @param callback
+   * @returns
+   */
   onWriteFile(callback: (data: TTSWriteType) => void) {
     this.emitter.on('writeFile', callback);
     return () => {
       this.emitter.off?.('writeFile', callback);
     };
   }
+  /**
+   * 缓冲区写入
+   * @TIPS 如果数据过小，音频在前端播放的时候，会卡顿
+   * @param callback
+   * @returns
+   */
+  onWriteFileBuffer(callback: (data: TTSWriteType) => void, opts?: { chunkSize?: number }) {
+    let index = 0;
+    let sendBuffer: Buffer = Buffer.alloc(0);
+    let chunkSize = opts?.chunkSize || 1024 * 50; // 50kb
+    const callbackBuff = (data: TTSWriteType) => {
+      index++;
+      if (data.isBegin) {
+        callback(data);
+        return;
+      }
+      const { data: videoBuffer } = data;
+      const sendValue = {
+        ...data,
+        index,
+      };
+      sendBuffer = Buffer.concat([sendBuffer, videoBuffer]);
+      const sendBufferLenght = Buffer.byteLength(sendBuffer);
+      if (sendBufferLenght > chunkSize) {
+        sendValue.data = sendBuffer;
+        callback(sendValue);
+        sendBuffer = Buffer.alloc(0);
+      } else if (data.isEnd) {
+        sendValue.data = sendBuffer;
+        callback(sendValue);
+        sendBuffer = Buffer.alloc(0);
+      }
+    };
+    this.emitter.on('writeFile', callbackBuff);
+    return () => {
+      this.emitter.off?.('writeFile', callbackBuff);
+    };
+  }
 }