Fix keyword spotting. (#1689)

Reset the stream right after detecting a keyword

wasm/kws/CMakeLists.txt

@@ -17,6 +17,7 @@ set(exported_functions
   SherpaOnnxIsKeywordStreamReady
   SherpaOnnxOnlineStreamAcceptWaveform
   SherpaOnnxOnlineStreamInputFinished
+  SherpaOnnxResetKeywordStream
 )
 set(mangled_exported_functions)
 foreach(x IN LISTS exported_functions)

wasm/kws/app.js

@@ -102,15 +102,17 @@ if (navigator.mediaDevices.getUserMedia) {
       recognizer_stream.acceptWaveform(expectedSampleRate, samples);
       while (recognizer.isReady(recognizer_stream)) {
         recognizer.decode(recognizer_stream);
-      }
 
+        let result = recognizer.getResult(recognizer_stream);
 
-      let result = recognizer.getResult(recognizer_stream);
+        if (result.keyword.length > 0) {
+          console.log(result)
+          lastResult = result;
+          resultList.push(JSON.stringify(result));
 
-      if (result.keyword.length > 0) {
-        console.log(result)
-        lastResult = result;
-        resultList.push(JSON.stringify(result));
+          // remember to reset the stream right after detecting a keyword
+          recognizer.reset(recognizer_stream);
+        }
       }
 
 

wasm/kws/sherpa-onnx-kws.js

@@ -296,8 +296,11 @@ class Kws {
   }
 
   decode(stream) {
-    return this.Module._SherpaOnnxDecodeKeywordStream(
-        this.handle, stream.handle);
+    this.Module._SherpaOnnxDecodeKeywordStream(this.handle, stream.handle);
+  }
+
+  reset(stream) {
+    this.Module._SherpaOnnxResetKeywordStream(this.handle, stream.handle);
   }
 
   getResult(stream) {