From 48d2e1696de860faf3bfc14f1b11c2d8a0cee601 Mon Sep 17 00:00:00 2001
From: Juha Heinanen <jh@tutpro.com>
Date: Fri, 30 Aug 2019 21:54:45 +0300
Subject: [PATCH] - Added support for Opus Forward Error Correction (FEC) via  
 Opus Expected Packet Loss configuration variable.

---
 .../com/tutpro/baresip/ConfigActivity.kt      | 36 ++++++++++++++++++-
 app/src/main/res/layout/activity_config.xml   | 34 ++++++++++++++++--
 app/src/main/res/values-fi/strings.xml        |  5 +++
 app/src/main/res/values/strings.xml           |  5 +++
 4 files changed, 77 insertions(+), 3 deletions(-)

diff --git a/app/src/main/kotlin/com/tutpro/baresip/ConfigActivity.kt b/app/src/main/kotlin/com/tutpro/baresip/ConfigActivity.kt
index 8ced7425..b1de6462 100644
--- a/app/src/main/kotlin/com/tutpro/baresip/ConfigActivity.kt
+++ b/app/src/main/kotlin/com/tutpro/baresip/ConfigActivity.kt
@@ -25,6 +25,7 @@ class ConfigActivity : AppCompatActivity() {
     internal lateinit var caFile: CheckBox
     internal lateinit var aec: CheckBox
     internal lateinit var opusBitRate: EditText
+    internal lateinit var opusPacketLoss: EditText
     internal lateinit var iceLite: CheckBox
     internal lateinit var debug: CheckBox
     internal lateinit var reset: CheckBox
@@ -37,6 +38,7 @@ class ConfigActivity : AppCompatActivity() {
     private var oldCAFile = false
     private var oldAec = false
     private var oldOpusBitrate = ""
+    private var oldOpusPacketLoss = ""
     private var oldIceMode = ""
     private var oldLogLevel = ""
     private var callVolume = BaresipService.callVolume
@@ -95,6 +97,11 @@ class ConfigActivity : AppCompatActivity() {
         oldOpusBitrate = if (obCv.size == 0) "28000" else obCv[0]
         opusBitRate.setText(oldOpusBitrate)
 
+        opusPacketLoss = findViewById(R.id.OpusPacketLoss) as EditText
+        val oplCv = Config.variable("opus_packet_loss")
+        oldOpusPacketLoss = if (oplCv.size == 0) "0" else oplCv[0]
+        opusPacketLoss.setText(oldOpusPacketLoss)
+
         iceLite = findViewById(R.id.IceLite) as CheckBox
         val imCv = Config.variable("ice_mode")
         oldIceMode = if (imCv.size == 0) "full" else imCv[0]
@@ -277,6 +284,23 @@ class ConfigActivity : AppCompatActivity() {
                 restart = true
             }
 
+            val opusPacketLoss = opusPacketLoss.text.toString().trim()
+            if (opusPacketLoss != oldOpusPacketLoss) {
+                if (!checkOpusPacketLoss(opusPacketLoss)) {
+                    Utils.alertView(this, "Notice",
+                            "Invalid Opus Packet Loss Percentage: $opusPacketLoss")
+                    return false
+                }
+                Config.remove("opus_inbandfec")
+                Config.remove("opus_packet_loss")
+                if (opusPacketLoss != "0") {
+                    Config.add("opus_inbandfec", "yes")
+                    Config.add("opus_bitrate", opusPacketLoss)
+                }
+                save = true
+                restart = true
+            }
+
             var iceModeString = "full"
             if (iceLite.isChecked) iceModeString = "lite"
             if (oldIceMode != iceModeString) {
@@ -357,6 +381,10 @@ class ConfigActivity : AppCompatActivity() {
                 Utils.alertView(this, getString(R.string.opus_bit_rate),
                         getString(R.string.opus_bit_rate_help))
             }
+            findViewById(R.id.OpusPacketLossTitle) as TextView-> {
+                Utils.alertView(this, getString(R.string.opus_packet_loss),
+                        getString(R.string.opus_packet_loss_help))
+            }
             findViewById(R.id.IceLiteTitle) as TextView-> {
                 Utils.alertView(this, getString(R.string.ice_lite_mode),
                         getString(R.string.ice_lite_mode_help))
@@ -385,7 +413,13 @@ class ConfigActivity : AppCompatActivity() {
     private fun checkOpusBitRate(opusBitRate: String): Boolean {
         val number = opusBitRate.toIntOrNull()
         if (number == null) return false
-        return (number >=6000) && (number <= 510000)
+        return (number >= 6000) && (number <= 510000)
+    }
+
+    private fun checkOpusPacketLoss(opusPacketLoss: String): Boolean {
+        val number = opusPacketLoss.toIntOrNull()
+        if (number == null) return false
+        return (number >= 0) && (number <= 100)
     }
 
     private fun addMissingPorts(addressList: String): String {
diff --git a/app/src/main/res/layout/activity_config.xml b/app/src/main/res/layout/activity_config.xml
index 4688330a..5ebcdb17 100644
--- a/app/src/main/res/layout/activity_config.xml
+++ b/app/src/main/res/layout/activity_config.xml
@@ -196,11 +196,10 @@
             </CheckBox>
         </RelativeLayout>
 
-
         <RelativeLayout
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
-            android:layout_marginBottom="12dp"
+            android:layout_marginBottom="0dp"
             android:orientation="horizontal" >
             <TextView
                 android:id="@+id/OpusBitRateTitle"
@@ -228,6 +227,37 @@
             </EditText>
         </RelativeLayout>
 
+        <RelativeLayout
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginBottom="12dp"
+            android:orientation="horizontal" >
+            <TextView
+                android:id="@+id/OpusPacketLossTitle"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_alignParentStart="true"
+                android:layout_centerVertical="true"
+                android:textSize="18sp"
+                android:textColor="@android:color/black"
+                android:onClick="onClick"
+                android:text="@string/opus_packet_loss" >
+            </TextView>
+            <EditText
+                android:id="@+id/OpusPacketLoss"
+                android:layout_height="wrap_content"
+                android:layout_width="fill_parent"
+                android:layout_centerVertical="true"
+                android:layout_toEndOf="@+id/OpusPacketLossTitle"
+                android:layout_marginStart="10dp"
+                android:textSize="18sp"
+                android:scrollHorizontally="true"
+                android:inputType="numberDecimal"
+                android:hint="@string/_0"
+                android:importantForAutofill="no" >
+            </EditText>
+        </RelativeLayout>
+
         <RelativeLayout
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
diff --git a/app/src/main/res/values-fi/strings.xml b/app/src/main/res/values-fi/strings.xml
index 830b797b..4c8d3def 100644
--- a/app/src/main/res/values-fi/strings.xml
+++ b/app/src/main/res/values-fi/strings.xml
@@ -192,6 +192,11 @@
     keskimääräinen enimmäisnopeus. Mahdollisia arvoja ovat
     6000-510000. Oletusarvo on 28000.
     </string>
+    <string name="opus_packet_loss">Odotettu Opus pakettihäviö</string>
+    <string name="opus_packet_loss_help">Odotettu Opus audio virran pakettihäviö prosentteina.
+        Mahdolliset arvot ovat 0-100. Oletusarvo on 0, jolloin ennakoiva virheenkorjaus
+        ei ole käytössä.</string>
+    <string name="_0" translatable="false">0</string>
     <string name="ice_lite_mode">ICE Lite-moodi</string>
     <string name="ice_lite_mode_help">Jos merkitty, ICE Lite-moodi on
     käytössä.
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 1e313c53..6a350f51 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -178,6 +178,11 @@ Check Apps → baresip → Permissions → Storage and that file \'accounts.bs\'
     <string name="opus_bit_rate_help">Average maximum bit rate used by Opus audio stream.
         Valid values are 6000-510000. Factory default is 28000.</string>
     <string name="_28000" translatable="false">28000</string>
+    <string name="opus_packet_loss">Opus Expected Packet Loss</string>
+    <string name="opus_packet_loss_help">Expected Opus audio stream packet loss percentage.
+        Valid values are 0-100. Factory default is 0, which disables Opus Forward Error
+        Correction (FEC).</string>
+    <string name="_0" translatable="false">0</string>
     <string name="ice_lite_mode">ICE Lite Mode</string>
     <string name="ice_lite_mode_help">If checked, ICE Lite Mode is used.</string>
     <string name="default_call_volume">Default Call Volume</string>