Add audio level monitoring capabilities in Visualizer effect

Extend the visualizer audio effect with the capability to query
 peak and RMS values for the currently playing audio.
Values are expressed in mB and are retrieved as an array of
 int values in the native layer, and written directly as
 object fields for the JNI.

Bug 8413913

Change-Id: I808075a18e61f85c566544a2bdaae10e5c4a644b

1 files changed, 72 insertions, 0 deletions

diff --git a/media/jni/audioeffect/android_media_Visualizer.cpp b/media/jni/audioeffect/android_media_Visualizer.cpp
index 4d77cfd..40cd06b 100644
--- a/media/jni/audioeffect/android_media_Visualizer.cpp
+++ b/media/jni/audioeffect/android_media_Visualizer.cpp
@@ -43,6 +43,8 @@ using namespace android;
 
 // ----------------------------------------------------------------------------
 static const char* const kClassPathName = "android/media/audiofx/Visualizer";
+static const char* const kClassPeakRmsPathName =
+        "android/media/audiofx/Visualizer$MeasurementPeakRms";
 
 struct fields_t {
     // these fields provide access from C++ to the...
@@ -50,6 +52,8 @@ struct fields_t {
     jmethodID midPostNativeEvent;   // event post callback method
     jfieldID  fidNativeVisualizer; // stores in Java the native Visualizer object
     jfieldID  fidJniData;           // stores in Java additional resources used by the native Visualizer
+    jfieldID  fidPeak; // to access Visualizer.MeasurementPeakRms.mPeak
+    jfieldID  fidRms;  // to access Visualizer.MeasurementPeakRms.mRms
 };
 static fields_t fields;
 
@@ -257,6 +261,14 @@ android_media_visualizer_native_init(JNIEnv *env)
 
     fields.clazzEffect = (jclass)env->NewGlobalRef(clazz);
 
+    // Get the Visualizer.MeasurementPeakRms class
+    clazz = env->FindClass(kClassPeakRmsPathName);
+    if (clazz == NULL) {
+        ALOGE("Can't find %s", kClassPeakRmsPathName);
+        return;
+    }
+    jclass clazzMeasurementPeakRms = (jclass)env->NewGlobalRef(clazz);
+
     // Get the postEvent method
     fields.midPostNativeEvent = env->GetStaticMethodID(
             fields.clazzEffect,
@@ -283,7 +295,24 @@ android_media_visualizer_native_init(JNIEnv *env)
         ALOGE("Can't find Visualizer.%s", "mJniData");
         return;
     }
+    //      fidPeak
+    fields.fidPeak = env->GetFieldID(
+            clazzMeasurementPeakRms,
+            "mPeak", "I");
+    if (fields.fidPeak == NULL) {
+        ALOGE("Can't find Visualizer.MeasurementPeakRms.%s", "mPeak");
+        return;
+    }
+    //      fidRms
+    fields.fidRms = env->GetFieldID(
+            clazzMeasurementPeakRms,
+            "mRms", "I");
+    if (fields.fidRms == NULL) {
+        ALOGE("Can't find Visualizer.MeasurementPeakRms.%s", "mPeak");
+        return;
+    }
 
+    env->DeleteGlobalRef(clazzMeasurementPeakRms);
 }
 
 static void android_media_visualizer_effect_callback(int32_t event,
@@ -513,6 +542,26 @@ android_media_visualizer_native_getScalingMode(JNIEnv *env, jobject thiz)
 }
 
 static jint
+android_media_visualizer_native_setMeasurementMode(JNIEnv *env, jobject thiz, jint mode)
+{
+    Visualizer* lpVisualizer = getVisualizer(env, thiz);
+    if (lpVisualizer == NULL) {
+        return VISUALIZER_ERROR_NO_INIT;
+    }
+    return translateError(lpVisualizer->setMeasurementMode(mode));
+}
+
+static jint
+android_media_visualizer_native_getMeasurementMode(JNIEnv *env, jobject thiz)
+{
+    Visualizer* lpVisualizer = getVisualizer(env, thiz);
+    if (lpVisualizer == NULL) {
+        return MEASUREMENT_MODE_NONE;
+    }
+    return lpVisualizer->getMeasurementMode();
+}
+
+static jint
 android_media_visualizer_native_getSamplingRate(JNIEnv *env, jobject thiz)
 {
     Visualizer* lpVisualizer = getVisualizer(env, thiz);
@@ -560,6 +609,25 @@ android_media_visualizer_native_getFft(JNIEnv *env, jobject thiz, jbyteArray jFf
 }
 
 static jint
+android_media_visualizer_native_getPeakRms(JNIEnv *env, jobject thiz, jobject jPeakRmsObj)
+{
+    Visualizer* lpVisualizer = getVisualizer(env, thiz);
+    if (lpVisualizer == NULL) {
+        return VISUALIZER_ERROR_NO_INIT;
+    }
+    int32_t measurements[2];
+    jint status = translateError(
+                lpVisualizer->getIntMeasurements(MEASUREMENT_MODE_PEAK_RMS,
+                        2, measurements));
+    if (status == VISUALIZER_SUCCESS) {
+        // measurement worked, write the values to the java object
+        env->SetIntField(jPeakRmsObj, fields.fidPeak, measurements[MEASUREMENT_IDX_PEAK]);
+        env->SetIntField(jPeakRmsObj, fields.fidRms, measurements[MEASUREMENT_IDX_RMS]);
+    }
+    return status;
+}
+
+static jint
 android_media_setPeriodicCapture(JNIEnv *env, jobject thiz, jint rate, jboolean jWaveform, jboolean jFft)
 {
     Visualizer* lpVisualizer = getVisualizer(env, thiz);
@@ -606,9 +674,13 @@ static JNINativeMethod gMethods[] = {
     {"native_getCaptureSize",    "()I",   (void *)android_media_visualizer_native_getCaptureSize},
     {"native_setScalingMode",    "(I)I",  (void *)android_media_visualizer_native_setScalingMode},
     {"native_getScalingMode",    "()I",   (void *)android_media_visualizer_native_getScalingMode},
+    {"native_setMeasurementMode","(I)I",  (void *)android_media_visualizer_native_setMeasurementMode},
+    {"native_getMeasurementMode","()I",   (void *)android_media_visualizer_native_getMeasurementMode},
     {"native_getSamplingRate",   "()I",   (void *)android_media_visualizer_native_getSamplingRate},
     {"native_getWaveForm",       "([B)I", (void *)android_media_visualizer_native_getWaveForm},
     {"native_getFft",            "([B)I", (void *)android_media_visualizer_native_getFft},
+    {"native_getPeakRms",      "(Landroid/media/audiofx/Visualizer$MeasurementPeakRms;)I",
+                                          (void *)android_media_visualizer_native_getPeakRms},
     {"native_setPeriodicCapture","(IZZ)I",(void *)android_media_setPeriodicCapture},
 };