java decode example for microphone (#122)

@@ -17,6 +17,8 @@ LIB_BUILD_DIR = ./lib
 
 EXAMPLE_FILE = DecodeFile.java
 
+EXAMPLE_Mic = DecodeMic.java
+
 JAVAC = javac
 
 BUILD_DIR = build
@@ -29,8 +31,11 @@ vpath %.class $(BUILD_DIR)
 vpath %.java src
 	
 	
-buildexample:  
+buildfile:  
 		$(JAVAC) -cp lib/sherpaonnx.jar -d $(BUILD_DIR) -encoding UTF-8 src/$(EXAMPLE_FILE)
+
+buildmic:  
+		$(JAVAC) -cp lib/sherpaonnx.jar -d $(BUILD_DIR) -encoding UTF-8 src/$(EXAMPLE_Mic)
 	
 rebuild: clean all
 	
@@ -43,10 +48,13 @@ clean:
 	mkdir -p ./lib
 
 	
-run:
+runfile:
 
-		java -cp ./lib/sherpaonnx.jar:build $(RUNJFLAGS)  DecodeFile 
+		java -cp ./lib/sherpaonnx.jar:build $(RUNJFLAGS)  DecodeFile
 
+runmic:
+
+		java -cp ./lib/sherpaonnx.jar:build $(RUNJFLAGS)  DecodeMic
 
 buildlib: $(LIB_FILES:.java=.class)
 	
@@ -58,4 +66,8 @@ buildlib: $(LIB_FILES:.java=.class)
 packjar:
 				jar cvfe lib/sherpaonnx.jar . -C $(BUILD_DIR) .
 				
-all: clean buildlib packjar buildexample run
+all: clean buildlib packjar buildfile buildmic
+
+
+
+

-
 0.Introduction
----
-Java wrapper `com.k2fsa.sherpaonnx.OnlineRecognizer` for `sherpa-onnx`. Java is a cross-platform language; you can build jni .so lib according to your system, and then use the same java api for all your platform.
-``` xml
+--------------
+
+Java wrapper `com.k2fsa.sherpa.onnx.OnlineRecognizer` for `sherpa-onnx`. Java is a cross-platform language; you can build jni .so lib according to your system, and then use the same java api for all your platform.
+
+```xml
 Depend on:
   Openjdk 1.8
 ```
+
 ---
+
 1.Compile libsherpa-onnx-jni.so
----
+-------------------------------
+
 Compile sherpa-onnx/jni/jni.cc according to your system.
 Example for Ubuntu 18.04 LTS, Openjdk 1.8.0_362:
-``` xml
+
+```xml
   git clone https://github.com/k2-fsa/sherpa-onnx
   cd sherpa-onnx
   mkdir build
@@ -19,14 +24,19 @@ Example for Ubuntu 18.04 LTS, Openjdk 1.8.0_362:
   cmake -DCMAKE_BUILD_TYPE=Release -DBUILD_SHARED_LIBS=ON -DSHERPA_ONNX_ENABLE_JNI=ON ..
   make -j6
 ```
+
 ---
+
 2.Download asr model files
----
+--------------------------
+
 [click here for more detail](https://k2-fsa.github.io/sherpa/onnx/pretrained_models/index.html)
----
+--------------------------
+
 3.Config model config.cfg
----
-``` xml 
+-------------------------
+
+```xml
   #model config  
   sample_rate=16000                  
   feature_dim=80
@@ -42,11 +52,15 @@ Example for Ubuntu 18.04 LTS, Openjdk 1.8.0_362:
   decoding_method=greedy_search
   max_active_paths=4
 ```
+
 ---
+
 4.A simple java example
----
+-----------------------
+
 refer to [java_api_example](https://github.com/k2-fsa/sherpa-onnx/blob/master/java-api-examples/src/DecodeFile.java) for more detail.
-``` java
+
+```java
     import com.k2fsa.sherpa.onnx.OnlineRecognizer;
     import com.k2fsa.sherpa.onnx.OnlineStream;
     String cfgpath=appdir+"/modelconfig.cfg";
@@ -71,18 +85,34 @@ refer to [java_api_example](https://github.com/k2-fsa/sherpa-onnx/blob/master/ja
     rcgOjb.reSet(streamObj);
     rcgOjb.releaseStream(streamObj); // release stream
     rcgOjb.release(); // release recognizer
-       
-
 ```
+
 ---
-5.Makefile 
----
-package jar and run app example
-package path: /sherpa-onnx/java-api-examples/lib/sherpaonnx.jar
-``` bash
+
+5.Makefile
+----------
+
+OS Ubuntu 18.04 LTS
+Build package path: /sherpa-onnx/java-api-examples/lib/sherpaonnx.jar
+
+5.1 Build
+
+```bash
     cd sherpa-onnx/java-api-examples
-    make all          
-	
-  ```
+    make all
+```
+
+5.2 Run DecodeFile example
+
+```bash
+    make runfile
+```
+
+5.3 Run DecodeMic example
+
+```bash
+    make runmic
+```
+
 
 

+/*
+ * // Copyright 2022-2023 by zhaoming
+ */
+/*
+Real-time speech recognition from a microphone with com.k2fsa.sherpa.onnx Java API
+
+example for cfgFile modelconfig.cfg
+  sample_rate=16000
+  feature_dim=80
+  rule1_min_trailing_silence=2.4
+  rule2_min_trailing_silence=1.2
+  rule3_min_utterance_length=20
+  encoder=/sherpa-onnx/build/bin/sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/encoder-epoch-99-avg-1.onnx
+  decoder=/sherpa-onnx/build/bin/sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/decoder-epoch-99-avg-1.onnx
+  joiner=/sherpa-onnx/build/bin/sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/joiner-epoch-99-avg-1.onnx
+  tokens=/sherpa-onnx/build/bin/sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/tokens.txt
+  num_threads=4
+  enable_endpoint_detection=true
+  decoding_method=greedy_search
+  max_active_paths=4
+
+*/
+import com.k2fsa.sherpa.onnx.OnlineRecognizer;
+import com.k2fsa.sherpa.onnx.OnlineStream;
+import java.io.*;
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.nio.ShortBuffer;
+import java.nio.charset.StandardCharsets;
+import javax.sound.sampled.AudioFormat;
+import javax.sound.sampled.AudioSystem;
+import javax.sound.sampled.DataLine;
+import javax.sound.sampled.TargetDataLine;
+
+/** Microphone Example */
+public class DecodeMic {
+  MicRcgThread micRcgThread = null; // thread handle
+
+  OnlineRecognizer rcgOjb; // the recognizer
+
+  OnlineStream streamObj; // the stream
+
+  public DecodeMic() {
+
+    micRcgThread = new MicRcgThread(); // create a new instance for MicRcgThread
+  }
+
+  public void open() {
+    micRcgThread.start(); // start to capture microphone data
+  }
+
+  public void close() {
+    micRcgThread.stop(); // close capture
+  }
+
+  /** init asr engine with config file */
+  public void initModelWithCfg(String cfgFile) {
+    try {
+
+      // set setSoPath() before running this
+      rcgOjb = new OnlineRecognizer(cfgFile);
+
+      streamObj = rcgOjb.createStream(); // create a stream for asr engine to feed data
+    } catch (Exception e) {
+      System.err.println(e);
+      e.printStackTrace();
+    }
+  }
+
+  /** read data from mic and feed to asr engine */
+  class MicRcgThread implements Runnable {
+
+    TargetDataLine capline; // line for capture mic data
+
+    Thread thread; // this thread
+    int segmentId = 0; // record the segment id when detect endpoint
+    String preText = ""; // decoded text
+
+    public MicRcgThread() {}
+
+    public void start() {
+
+      thread = new Thread(this);
+
+      thread.start(); // start thread
+    }
+
+    public void stop() {
+      capline.stop();
+      capline.close();
+      capline = null;
+      thread = null;
+    }
+
+    /** feed captured microphone data to asr */
+    public void decodeSample(byte[] samplebytes) {
+      try {
+        ByteBuffer byteBuf = ByteBuffer.wrap(samplebytes); // create a bytebuf for samples
+        byteBuf.order(ByteOrder.LITTLE_ENDIAN); // set bytebuf to little endian
+        ShortBuffer shortBuf = byteBuf.asShortBuffer(); // covert to short type
+        short[] arrShort = new short[shortBuf.capacity()]; // array for copy short data
+        float[] arrFloat = new float[shortBuf.capacity()]; // array for copy float data
+        shortBuf.get(arrShort); // put date to arrShort
+
+        for (int i = 0; i < arrShort.length; i++) {
+          arrFloat[i] = arrShort[i] / 32768f; // loop to covert short data to float -1 to 1
+        }
+        streamObj.acceptWaveform(arrFloat); // feed asr engine with float data
+        while (rcgOjb.isReady(streamObj)) { // if engine is ready for unprocessed data
+
+          rcgOjb.decodeStream(streamObj); // decode for this stream
+        }
+        boolean isEndpoint =
+            rcgOjb.isEndpoint(
+                streamObj); // endpoint check, make sure enable_endpoint_detection=true in config
+                            // file
+        String nowText = rcgOjb.getResult(streamObj); // get asr result
+        String recText = "";
+        byte[] utf8Data; // for covert text to utf8
+        if (isEndpoint && nowText.length() > 0) {
+          rcgOjb.reSet(streamObj); // reSet stream when detect endpoint
+          segmentId++;
+          preText = nowText;
+          recText = "text(seg_" + String.valueOf(segmentId) + "):" + nowText + "\n";
+          utf8Data = recText.getBytes(StandardCharsets.UTF_8);
+          System.out.println(new String(utf8Data));
+        }
+
+        if (!nowText.equals(preText)) { // if preText not equal nowtext
+          preText = nowText;
+          recText = nowText + "\n";
+          utf8Data = recText.getBytes(StandardCharsets.UTF_8);
+          System.out.println(new String(utf8Data));
+        }
+      } catch (Exception e) {
+        System.err.println(e);
+        e.printStackTrace();
+      }
+    }
+
+    /** run mic capture thread */
+    public void run() {
+      System.out.println("Started! Please speak...");
+
+      AudioFormat.Encoding encoding = AudioFormat.Encoding.PCM_SIGNED; // the pcm format
+      float rate = 16000.0f; // using 16 kHz
+      int channels = 1; // single channel
+      int sampleSize = 16; // sampleSize 16bit
+      boolean isBigEndian = false; // using little endian
+
+      AudioFormat format =
+          new AudioFormat(
+              encoding, rate, sampleSize, channels, (sampleSize / 8) * channels, rate, isBigEndian);
+
+      DataLine.Info info = new DataLine.Info(TargetDataLine.class, format);
+
+      // check system support such data format
+      if (!AudioSystem.isLineSupported(info)) {
+        System.out.println(info + " not supported.");
+        return;
+      }
+
+      // open a line for capture.
+
+      try {
+        capline = (TargetDataLine) AudioSystem.getLine(info);
+        capline.open(format, capline.getBufferSize());
+      } catch (Exception ex) {
+        System.out.println(ex);
+        return;
+      }
+
+      // the buf size for mic captured each time
+      int bufferLengthInBytes = capline.getBufferSize() / 8 * format.getFrameSize();
+      byte[] micData = new byte[bufferLengthInBytes];
+      int numBytesRead;
+
+      capline.start(); // start to capture mic data
+
+      while (thread != null) {
+        // read data from line
+        if ((numBytesRead = capline.read(micData, 0, bufferLengthInBytes)) == -1) {
+          break;
+        }
+
+        decodeSample(micData); // decode mic data
+      }
+
+      // stop and close
+
+      try {
+        if (capline != null) {
+          capline.stop();
+          capline.close();
+          capline = null;
+        }
+
+      } catch (Exception ex) {
+        System.err.println(ex);
+      }
+    }
+  } // End class DecodeMic
+
+  public static void main(String s[]) {
+    try {
+      String appDir = System.getProperty("user.dir");
+      System.out.println("appdir=" + appDir);
+      String cfgPath = appDir + "/modelconfig.cfg";
+      String soPath = appDir + "/../build/lib/libsherpa-onnx-jni.so";
+      OnlineRecognizer.setSoPath(soPath); // set so. lib for OnlineRecognizer
+
+      DecodeMic decodeEx = new DecodeMic();
+      decodeEx.initModelWithCfg(cfgPath); // init asr engine
+      decodeEx.open(); // open thread for mic
+      System.out.print("Press Enter to EXIT!\n");
+      char i = (char) System.in.read();
+      decodeEx.close();
+    } catch (Exception e) {
+      System.err.println(e);
+      e.printStackTrace();
+    }
+  }
+}