Initial implementation of polymorphic input mode handling.

4 files changed, 163 insertions, 0 deletions

diff --git a/src/main/java/com/morlunk/jumble/audio/inputmode/ActivityInputMode.java b/src/main/java/com/morlunk/jumble/audio/inputmode/ActivityInputMode.java
new file mode 100644
index 0000000..bd96b30
--- /dev/null
+++ b/src/main/java/com/morlunk/jumble/audio/inputmode/ActivityInputMode.java
@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2016 Andrew Comminos <andrew@comminos.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.morlunk.jumble.audio.inputmode;
+
+/**
+ * An input mode that sends audio if the amplitude exceeds a certain threshold.
+ * Created by andrew on 13/02/16.
+ */
+public class ActivityInputMode implements IInputMode {
+    // Continue speech for 250ms to prevent dropping.
+    private static final int SPEECH_DELAY = (int) (0.25 * Math.pow(10, 9));
+
+    private final float mVADThreshold;
+    private long mVADLastDetected;
+
+    public ActivityInputMode(float detectionThreshold) {
+        mVADThreshold = detectionThreshold;
+    }
+
+    @Override
+    public boolean onInputReceived(short[] pcm, int length) {
+        // Use a logarithmic energy-based scale for VAD.
+        float sum = 1.0f;
+        for (int i = 0; i < length; i++) {
+            sum += pcm[i] * pcm[i];
+        }
+        float micLevel = (float) Math.sqrt(sum / (float)length);
+        float peakSignal = (float) (20.0f * Math.log10(micLevel / 32768.0f)) / 96.0f;
+        boolean talking = (peakSignal + 1) >= mVADThreshold;
+
+        talking |= (System.nanoTime() - mVADLastDetected) < SPEECH_DELAY;
+
+        // Record the last time where VAD was detected in order to prevent speech dropping.
+        if(talking) {
+            mVADLastDetected = System.nanoTime();
+        }
+
+        return talking;
+    }
+}
diff --git a/src/main/java/com/morlunk/jumble/audio/inputmode/ContinuousInputMode.java b/src/main/java/com/morlunk/jumble/audio/inputmode/ContinuousInputMode.java
new file mode 100644
index 0000000..cd0c282
--- /dev/null
+++ b/src/main/java/com/morlunk/jumble/audio/inputmode/ContinuousInputMode.java
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2016 Andrew Comminos <andrew@comminos.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.morlunk.jumble.audio.inputmode;
+
+/**
+ * An input mode that always transmits audio.
+ * Created by andrew on 13/02/16.
+ */
+public class ContinuousInputMode implements IInputMode {
+    @Override
+    public boolean onInputReceived(short[] pcm, int length) {
+        return true;
+    }
+}
diff --git a/src/main/java/com/morlunk/jumble/audio/inputmode/IInputMode.java b/src/main/java/com/morlunk/jumble/audio/inputmode/IInputMode.java
new file mode 100644
index 0000000..78f4cf8
--- /dev/null
+++ b/src/main/java/com/morlunk/jumble/audio/inputmode/IInputMode.java
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2016 Andrew Comminos <andrew@comminos.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.morlunk.jumble.audio.inputmode;
+
+/**
+ * A talk state engine, providing information regarding when it is appropriate to send audio.
+ * Created by andrew on 13/02/16.
+ */
+public interface IInputMode {
+    /**
+     * Called when new input is received from the audio recording thread.
+     * @param pcm PCM data.
+     * @param length The number of shorts in the PCM data.
+     * @return true if the input should be transmitted.
+     */
+    boolean onInputReceived(short[] pcm, int length);
+}
diff --git a/src/main/java/com/morlunk/jumble/audio/inputmode/ToggleInputMode.java b/src/main/java/com/morlunk/jumble/audio/inputmode/ToggleInputMode.java
new file mode 100644
index 0000000..8466805
--- /dev/null
+++ b/src/main/java/com/morlunk/jumble/audio/inputmode/ToggleInputMode.java
@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2016 Andrew Comminos <andrew@comminos.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.morlunk.jumble.audio.inputmode;
+
+/**
+ * An input mode that depends on a toggle, such as push to talk.
+ * Created by andrew on 13/02/16.
+ */
+public class ToggleInputMode implements IInputMode {
+    private boolean mInputOn;
+
+    public ToggleInputMode() {
+        mInputOn = false;
+    }
+
+    public void toggleTalkingOn() {
+        mInputOn = !mInputOn;
+    }
+
+    public boolean isTalkingOn() {
+        return mInputOn;
+    }
+
+    public void setTalkingOn(boolean talking) {
+        mInputOn = talking;
+    }
+
+    @Override
+    public boolean onInputReceived(short[] pcm, int length) {
+        return mInputOn;
+    }
+}