OboeTester needs volume report in Recorder (#2120)

apps/OboeTester/app/src/main/cpp/NativeAudioContext.cpp

@@ -715,6 +715,47 @@ oboe::Result ActivityRecording::startPlayback() {
     return result;
 }
 
+ActivityRecording::RecordingStats ActivityRecording::computeRecordingStats() {
+    constexpr int chunkFrames = 512;
+
+    mRecording->rewind();
+
+    const int ch = mRecording->getChannelCount();
+    auto buffer = std::make_unique<float[]>(chunkFrames * ch);
+
+    const int32_t totalFrames = mRecording->getSizeInFrames();
+    int32_t frameIndex = 0;
+
+    RecordingStats recordingStats;
+
+    while (frameIndex < totalFrames) {
+        const int framesToRead = std::min<int>(chunkFrames, totalFrames - frameIndex);
+        const int framesRead = mRecording->read(buffer.get(), framesToRead);
+        if (framesRead <= 0) break;
+
+        const int samplesRead = framesRead * ch;
+
+        for (int i = 0; i < samplesRead; ++i) {
+            const double x = buffer[i];
+            recordingStats.peakAbs = std::max(recordingStats.peakAbs, std::abs(x));
+            recordingStats.sumSq += x * x;
+        }
+        recordingStats.n += samplesRead;
+
+        frameIndex += framesRead;
+
+        bool lastRemainingFramesRead = framesRead < framesToRead;
+        if (lastRemainingFramesRead) break;
+    }
+
+    return recordingStats;
+}
+
+ActivityRecording::RecordingStats ActivityRecording::getRecordingStats() {
+    return computeRecordingStats();
+}
+
+
 // ======================================================================= ActivityTapToTone
 void ActivityTapToTone::configureAfterOpen() {
     monoToMulti = std::make_unique<MonoToMultiConverter>(mChannelCount);

apps/OboeTester/app/src/main/cpp/NativeAudioContext.h

@@ -456,6 +456,15 @@ class ActivityRecording : public ActivityTestInput {
     PlayRecordingCallback        mPlayRecordingCallback;
     oboe::AudioStream           *playbackStream = nullptr;
 
+    struct RecordingStats {
+        double peakAbs = 0.0;
+        double sumSq   = 0.0;
+        int64_t n      = 0;      // total samples
+    };
+
+    RecordingStats computeRecordingStats();
+
+    ActivityRecording::RecordingStats getRecordingStats();
 };
 
 /**

apps/OboeTester/app/src/main/cpp/jni-bridge.cpp

@@ -59,6 +59,9 @@ static jfieldID g_stretchModeField = nullptr;
 static jfieldID g_pitchField = nullptr;
 static jfieldID g_speedField = nullptr;
 
+static jclass g_recordingStatsClass = nullptr;
+static jmethodID g_recordingStatsConstructor = nullptr;
+
 JNIEXPORT jint JNICALL
 Java_com_mobileer_oboetester_OboeAudioStream_openNative(JNIEnv *env, jobject,
                                                        jint nativeApi,
@@ -1117,6 +1120,16 @@ Java_com_mobileer_oboetester_ManualGlitchActivity_getRecentSamples(JNIEnv *env,
     return numSamples;
 }
 
+JNIEXPORT jobject JNICALL
+Java_com_mobileer_oboetester_RecorderActivity_getRecordingStatsJni(JNIEnv *env, jobject) {
+
+    ActivityRecording::RecordingStats params = engine.mActivityRecording.getRecordingStats();
+
+    return env->NewObject(g_recordingStatsClass, g_recordingStatsConstructor,
+                          (jfloat)params.peakAbs,
+                          (params.n > 0) ? (float)std::sqrt(params.sumSq / (float)params.n) : 0.0F);
+}
+
 JNIEXPORT void JNICALL
 Java_com_mobileer_oboetester_TestAudioActivity_setDefaultAudioValues(JNIEnv *env, jclass clazz,
                                                                      jint audio_manager_sample_rate,
@@ -1401,6 +1414,28 @@ JNIEXPORT jint JNICALL JNI_OnLoad(JavaVM* vm, void* reserved) {
         return JNI_ERR;
     }
 
+    const char* recordingStatsClassName = "com/mobileer/oboetester/RecordingStats";
+    jclass localRecordingStatsClass = env->FindClass(recordingStatsClassName);
+    if (localRecordingStatsClass == nullptr) {
+        LOGE("JNI_OnLoad: Could not find class %s", recordingStatsClassName);
+        if (env->ExceptionCheck()) env->ExceptionDescribe();
+        return JNI_ERR;
+    }
+    g_recordingStatsClass = (jclass)env->NewGlobalRef(localRecordingStatsClass);
+    env->DeleteLocalRef(localRecordingStatsClass);
+    if (g_recordingStatsClass == nullptr) {
+        LOGE("JNI_OnLoad: Could not create global ref for %s", recordingStatsClassName);
+        return JNI_ERR;
+    }
+
+    g_recordingStatsConstructor = env->GetMethodID(
+            g_recordingStatsClass, "<init>", "(FF)V");
+    if (g_recordingStatsConstructor == nullptr) {
+        LOGE("JNI_OnLoad: Could not find constructor for %s", recordingStatsClassName);
+        if (env->ExceptionCheck()) env->ExceptionDescribe();
+        return JNI_ERR;
+    }
+
     g_fallbackModeField = env->GetFieldID(g_playbackParametersClass, "mFallbackMode", "I");
     g_stretchModeField = env->GetFieldID(g_playbackParametersClass, "mStretchMode", "I");
     g_pitchField = env->GetFieldID(g_playbackParametersClass, "mPitch", "F");

apps/OboeTester/app/src/main/java/com/mobileer/oboetester/RecorderActivity.java

@@ -19,6 +19,7 @@
 import android.os.Bundle;
 import android.view.View;
 import android.widget.Button;
+import android.widget.TextView;
 
 import java.io.IOException;
 
@@ -34,6 +35,7 @@ public class RecorderActivity extends TestInputActivity {
     private Button mStopButton;
     private Button mPlayButton;
     private Button mShareButton;
+    private TextView mStatusView;
     private boolean mGotRecording;
 
     @Override
@@ -49,6 +51,7 @@ protected void onCreate(Bundle savedInstanceState) {
         mStopButton = (Button) findViewById(R.id.button_stop_record_play);
         mPlayButton = (Button) findViewById(R.id.button_start_playback);
         mShareButton = (Button) findViewById(R.id.button_share);
+        mStatusView = (TextView) findViewById(R.id.status_view);
         mRecorderState = AUDIO_STATE_STOPPED;
         mGotRecording = false;
         updateButtons();
@@ -75,6 +78,19 @@ public void onStopRecordPlay(View view) {
         closeAudio();
         mRecorderState = AUDIO_STATE_STOPPED;
         updateButtons();
+
+        StringBuilder text = new StringBuilder();
+        for (StreamContext streamContext: mStreamContexts) {
+            RecordingStats recordingStats = getRecordingStatsJni();
+            text
+                .append("Peak amplitude: ")
+                .append(recordingStats.peak)
+                .append("\n")
+                .append("Rms: ")
+                .append(recordingStats.rms)
+                .append("\n");
+        }
+        mStatusView.setText(text);
     }
 
     public void onStartPlayback(View view) {
@@ -106,4 +122,5 @@ String getWaveTag() {
         return "recording";
     }
 
+    private native RecordingStats getRecordingStatsJni();
 }

apps/OboeTester/app/src/main/java/com/mobileer/oboetester/RecordingStats.java

@@ -0,0 +1,11 @@
+package com.mobileer.oboetester;
+
+public final class RecordingStats {
+    public final float peak;
+    public final float rms;
+
+    public RecordingStats(float peak, float rms) {
+        this.peak = peak;
+        this.rms = rms;
+    }
+}

apps/OboeTester/app/src/main/res/layout/activity_recorder.xml

@@ -98,7 +98,7 @@
         </LinearLayout>
 
         <TextView
-            android:id="@+id/statusView"
+            android:id="@+id/status_view"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:lines="3"