detect the silence of audio

app/src/main/java/com/frank/ffmpeg/activity/AudioHandleActivity.kt

@@ -105,7 +105,8 @@ class AudioHandleActivity : BaseActivity() {
                 R.id.btn_audio_speed,
                 R.id.btn_audio_echo,
                 R.id.btn_audio_tremolo,
-                R.id.btn_audio_denoise
+                R.id.btn_audio_denoise,
+                R.id.btn_audio_silence
         )
     }
 
@@ -241,6 +242,10 @@ class AudioHandleActivity : BaseActivity() {
                 val noisePath = PATH + File.separator + "denoise.mp3"
                 commandLine = FFmpegUtil.audioDenoise(srcFile, noisePath)
             }
+            R.id.btn_audio_silence
+            -> {
+                commandLine = FFmpegUtil.audioSilenceDetect(srcFile)
+            }
             else -> {
             }
         }

app/src/main/java/com/frank/ffmpeg/util/FFmpegUtil.java

@@ -91,7 +91,6 @@ public class FFmpegUtil {
      * @param inputPath  input file
      * @param delay      delay to play
      * @param outputPath output file
-     * @return mix success or not
      */
     public static String[] audioEcho(String inputPath, int delay, String outputPath) {
         // in_gain (0, 1], Default is 0.6
@@ -110,7 +109,6 @@ public class FFmpegUtil {
      * @param frequency  frequency
      * @param depth      depth
      * @param outputPath output file
-     * @return mix success or not
      */
     public static String[] audioTremolo(String inputPath, int frequency, float depth, String outputPath) {
         // frequency [0.1, 20000.0], Default is 5
@@ -125,7 +123,6 @@ public class FFmpegUtil {
      *
      * @param inputPath  input file
      * @param outputPath output file
-     * @return mix success or not
      */
     public static String[] audioDenoise(String inputPath, String outputPath) {
         // nr: noise reduction in dB, [0.01 to 97], Default value is 12 dB
@@ -136,6 +133,19 @@ public class FFmpegUtil {
         return fftDenoiseCmd.split(" ");
     }
 
+    /**
+     * Detect silence of a chunk of audio
+     *
+     * @param inputPath  input file
+     */
+    public static String[] audioSilenceDetect(String inputPath) {
+        // silence_start: 268.978
+        // silence_end: 271.048 | silence_duration: 2.06975
+        String silenceCmd = "ffmpeg -i %s -af silencedetect=noise=0.0001 -f null -";
+        silenceCmd = String.format(Locale.getDefault(), silenceCmd, inputPath);
+        return silenceCmd.split(" ");
+    }
+
     /**
      * mux audio and video together
      *

app/src/main/res/layout/activity_audio_handle.xml

@@ -44,14 +44,16 @@
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:text="@string/audio_play"
-            android:layout_marginTop="10dp" />
+            android:layout_marginTop="10dp"
+            android:visibility="gone"/>
 
         <Button
             android:id="@+id/btn_play_opensl"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:text="@string/audio_opensl"
-            android:layout_marginTop="10dp" />
+            android:layout_marginTop="10dp"
+            android:visibility="gone"/>
 
         <Button
             android:id="@+id/btn_audio_encode"
@@ -97,6 +99,13 @@
             android:text="@string/audio_denoise"
             android:layout_marginTop="10dp" />
 
+        <Button
+            android:id="@+id/btn_audio_silence"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:text="@string/audio_silence"
+            android:layout_marginTop="10dp" />
+
     </LinearLayout>
 
     <include

app/src/main/res/values-en/strings.xml

@@ -12,6 +12,7 @@
     <string name="audio_echo">Echo effect</string>
     <string name="audio_tremolo">Tremolo effect</string>
     <string name="audio_denoise">Audio denoise</string>
+    <string name="audio_silence">Silence detect</string>
     <string name="audio_effect">Audio effect</string>
     <string name="audio_equalizer">Audio equalizer:</string>
     <string name="audio_style">Audio style:</string>

app/src/main/res/values/strings.xml

@@ -12,6 +12,7 @@
     <string name="audio_echo">空灵效果</string>
     <string name="audio_tremolo">惊悚效果</string>
     <string name="audio_denoise">音频降噪</string>
+    <string name="audio_silence">静音检测</string>
     <string name="audio_effect">音乐均衡器</string>
     <string name="audio_equalizer">均衡器:</string>
     <string name="audio_style">风格:</string>

gradlew

@@ -158,3 +158,4 @@ eval splitJvmOpts $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS
 JVM_OPTS[${#JVM_OPTS[*]}]="-Dorg.gradle.appname=$APP_BASE_NAME"
 
 exec "$JAVACMD" "${JVM_OPTS[@]}" -classpath "$CLASSPATH" org.gradle.wrapper.GradleWrapperMain "$@"
+