Add TTS for node-addon-api (#871)

scripts/node-addon-api/lib/addon.js

@@ -25,8 +25,8 @@ for (const p of possible_paths) {
 }
 
 if (!found) {
-  let msg =
-      `Could not find sherpa-onnx. Tried\n\n  ${possible_paths.join('\n  ')}\n`
+  let msg = `Could not find sherpa-onnx-node. Tried\n\n  ${
+      possible_paths.join('\n  ')}\n`
   if (os.platform() == 'darwin' && process.env.DYLD_LIBRARY_PATH &&
       !process.env.DYLD_LIBRARY_PATH.includes(
           `node_modules/sherpa-onnx-${platform_arch}`)) {

scripts/node-addon-api/lib/non-streaming-tts.js

@@ -0,0 +1,25 @@
+const addon = require('./addon.js');
+
+class OfflineTts {
+  constructor(config) {
+    this.handle = addon.createOfflineTts(config);
+    this.config = config;
+
+    this.numSpeakers = addon.getOfflineTtsNumSpeakers(this.handle);
+    this.sampleRate = addon.getOfflineTtsSampleRate(this.handle);
+  }
+
+  /*
+   input obj: {text: "xxxx", sid: 0, speed: 1.0}
+   where text is a string, sid is a int32, speed is a float
+
+   return an object {samples: Float32Array, sampleRate: <a number>}
+   */
+  generate(obj) {
+    return addon.offlineTtsGenerate(this.handle, obj);
+  }
+}
+
+module.exports = {
+  OfflineTts,
+}

scripts/node-addon-api/lib/sherpa-onnx.js

@@ -1,11 +1,13 @@
 const addon = require('./addon.js')
 const streaming_asr = require('./streaming-asr.js');
 const non_streaming_asr = require('./non-streaming-asr.js');
+const non_streaming_tts = require('./non-streaming-tts.js');
 const vad = require('./vad.js');
 
 module.exports = {
   OnlineRecognizer: streaming_asr.OnlineRecognizer,
   OfflineRecognizer: non_streaming_asr.OfflineRecognizer,
+  OfflineTts: non_streaming_tts.OfflineTts,
   readWave: addon.readWave,
   writeWave: addon.writeWave,
   Display: streaming_asr.Display,