Refactor WebAssembly build script. (#598)

Make it easier to build WebAssembly for ASR.

wasm/tts/sherpa-onnx.js

@@ -0,0 +1,180 @@
+
+function freeConfig(config) {
+  if ('buffer' in config) {
+    _free(config.buffer);
+  }
+
+  if ('config' in config) {
+    freeConfig(config.config)
+  }
+
+  _free(config.ptr);
+}
+
+// The user should free the returned pointers
+function initSherpaOnnxOfflineTtsVitsModelConfig(config) {
+  let modelLen = lengthBytesUTF8(config.model) + 1;
+  let lexiconLen = lengthBytesUTF8(config.lexicon) + 1;
+  let tokensLen = lengthBytesUTF8(config.tokens) + 1;
+  let dataDirLen = lengthBytesUTF8(config.dataDir) + 1;
+
+  let n = modelLen + lexiconLen + tokensLen + dataDirLen;
+
+  let buffer = _malloc(n);
+
+  let len = 7 * 4;
+  let ptr = _malloc(len);
+
+  let offset = 0;
+  stringToUTF8(config.model, buffer + offset, modelLen);
+  offset += modelLen;
+
+  stringToUTF8(config.lexicon, buffer + offset, lexiconLen);
+  offset += lexiconLen;
+
+  stringToUTF8(config.tokens, buffer + offset, tokensLen);
+  offset += tokensLen;
+
+  stringToUTF8(config.dataDir, buffer + offset, dataDirLen);
+  offset += dataDirLen;
+
+  offset = 0;
+  setValue(ptr, buffer + offset, 'i8*');
+  offset += modelLen;
+
+  setValue(ptr + 4, buffer + offset, 'i8*');
+  offset += lexiconLen;
+
+  setValue(ptr + 8, buffer + offset, 'i8*');
+  offset += tokensLen;
+
+  setValue(ptr + 12, buffer + offset, 'i8*');
+  offset += dataDirLen;
+
+  setValue(ptr + 16, config.noiseScale, 'float');
+  setValue(ptr + 20, config.noiseScaleW, 'float');
+  setValue(ptr + 24, config.lengthScale, 'float');
+
+  return {
+    buffer: buffer, ptr: ptr, len: len,
+  }
+}
+
+function initSherpaOnnxOfflineTtsModelConfig(config) {
+  let vitsModelConfig =
+      initSherpaOnnxOfflineTtsVitsModelConfig(config.offlineTtsVitsModelConfig);
+
+  let len = vitsModelConfig.len + 3 * 4;
+  let ptr = _malloc(len);
+
+  let offset = 0;
+  _CopyHeap(vitsModelConfig.ptr, vitsModelConfig.len, ptr + offset);
+  offset += vitsModelConfig.len;
+
+  setValue(ptr + offset, config.numThreads, 'i32');
+  offset += 4;
+
+  setValue(ptr + offset, config.debug, 'i32');
+  offset += 4;
+
+  let providerLen = lengthBytesUTF8(config.provider) + 1;
+  let buffer = _malloc(providerLen);
+  stringToUTF8(config.provider, buffer, providerLen);
+  setValue(ptr + offset, buffer, 'i8*');
+
+  return {
+    buffer: buffer, ptr: ptr, len: len, config: vitsModelConfig,
+  }
+}
+
+function initSherpaOnnxOfflineTtsConfig(config) {
+  let modelConfig =
+      initSherpaOnnxOfflineTtsModelConfig(config.offlineTtsModelConfig);
+  let len = modelConfig.len + 2 * 4;
+  let ptr = _malloc(len);
+
+  let offset = 0;
+  _CopyHeap(modelConfig.ptr, modelConfig.len, ptr + offset);
+  offset += modelConfig.len;
+
+  let ruleFstsLen = lengthBytesUTF8(config.ruleFsts) + 1;
+  let buffer = _malloc(ruleFstsLen);
+  stringToUTF8(config.ruleFsts, buffer, ruleFstsLen);
+  setValue(ptr + offset, buffer, 'i8*');
+  offset += 4;
+
+  setValue(ptr + offset, config.maxNumSentences, 'i32');
+
+  return {
+    buffer: buffer, ptr: ptr, len: len, config: modelConfig,
+  }
+}
+
+class OfflineTts {
+  constructor(configObj) {
+    let config = initSherpaOnnxOfflineTtsConfig(configObj)
+    let handle = _SherpaOnnxCreateOfflineTts(config.ptr);
+
+    freeConfig(config);
+
+    this.handle = handle;
+    this.sampleRate = _SherpaOnnxOfflineTtsSampleRate(this.handle);
+    this.numSpeakers = _SherpaOnnxOfflineTtsNumSpeakers(this.handle);
+  }
+
+  free() {
+    _SherpaOnnxDestroyOfflineTts(this.handle);
+    this.handle = 0
+  }
+
+  // {
+  //   text: "hello",
+  //   sid: 1,
+  //   speed: 1.0
+  // }
+  generate(config) {
+    let textLen = lengthBytesUTF8(config.text) + 1;
+    let textPtr = _malloc(textLen);
+    stringToUTF8(config.text, textPtr, textLen);
+
+    let h = _SherpaOnnxOfflineTtsGenerate(
+        this.handle, textPtr, config.sid, config.speed);
+
+    let numSamples = HEAP32[h / 4 + 1];
+    let sampleRate = HEAP32[h / 4 + 2];
+
+    let samplesPtr = HEAP32[h / 4] / 4;
+    let samples = new Float32Array(numSamples);
+    for (let i = 0; i < numSamples; i++) {
+      samples[i] = HEAPF32[samplesPtr + i];
+    }
+
+    _SherpaOnnxDestroyOfflineTtsGeneratedAudio(h);
+    return {samples: samples, sampleRate: sampleRate};
+  }
+}
+
+function initSherpaOnnxOfflineTts() {
+  let offlineTtsVitsModelConfig = {
+    model: './model.onnx',
+    lexicon: '',
+    tokens: './tokens.txt',
+    dataDir: './espeak-ng-data',
+    noiseScale: 0.667,
+    noiseScaleW: 0.8,
+    lengthScale: 1.0,
+  };
+  let offlineTtsModelConfig = {
+    offlineTtsVitsModelConfig: offlineTtsVitsModelConfig,
+    numThreads: 1,
+    debug: 1,
+    provider: 'cpu',
+  };
+  let offlineTtsConfig = {
+    offlineTtsModelConfig: offlineTtsModelConfig,
+    ruleFsts: '',
+    maxNumSentences: 1,
+  }
+
+  return new OfflineTts(offlineTtsConfig);
+}