Merge pull request #17 from DolbyIO/develop

Fix calculatePacketsLostRatio

Author: FabienLavocat

README.md

@@ -4,7 +4,7 @@
 [![npm](https://img.shields.io/npm/v/@dolbyio/webrtc-stats)](https://www.npmjs.com/package/@dolbyio/webrtc-stats)
 [![License](https://img.shields.io/github/license/DolbyIO/web-webrtc-stats)](LICENSE)
 
-# Dolby.io WebRTC Statistics
+# Dolby OptiView WebRTC Statistics
 
 This project is a library to use to parse WebRTC statistics.
 
@@ -87,7 +87,7 @@ const tokenGenerator = () =>
         streamName: STREAM_NAME,
     });
 
-const publisher = new Publish(STREAM_NAME, tokenGenerator);
+const publisher = new Publish(undefined, tokenGenerator);
 
 // HERE: Publish a stream to Dolby OptiView
 

package-lock.json

@@ -1,7 +1,7 @@
 {
     "name": "@dolbyio/webrtc-stats",
-    "version": "1.0.3",
-    "description": "Dolby.io WebRTC Statistics",
+    "version": "1.0.4",
+    "description": "Dolby OptiView WebRTC Statistics",
     "main": "dist/webrtc-stats.js",
     "typings": "dist/index.d.ts",
     "scripts": {
@@ -23,7 +23,8 @@
         "stats",
         "statistics",
         "dolbyio",
-        "millicast"
+        "millicast",
+        "optiview"
     ],
     "files": [
         "dist/*",

package.json

@@ -26,11 +26,13 @@ export const calculatePacketsLostRatio = (
     lastTotalPacketsLost?: number,
     lastTotalPacketsReceived?: number
 ): number => {
-    if (totalPacketsReceived == 0) {
+    const currentLostPackets = totalPacketsLost - (lastTotalPacketsLost ?? 0);
+    const currentReceivedPackets = totalPacketsReceived - (lastTotalPacketsReceived ?? 0);
+    const currentPacketsExpected = currentLostPackets + currentReceivedPackets;
+
+    if (currentPacketsExpected === 0) {
         return 0;
     }
 
-    const currentLostPackages = totalPacketsLost - (lastTotalPacketsLost ?? 0);
-    const currentReceivedPackages = totalPacketsReceived - (lastTotalPacketsReceived ?? 0);
-    return currentLostPackages / currentReceivedPackages;
+    return currentLostPackets / currentPacketsExpected;
 };

src/utils.ts

@@ -247,7 +247,7 @@ export class WebRTCStats extends EventEmitter implements WebRTCStats {
     async #getInputAudio(rtcStatsReport: RTCStatsReport, entry: RTCInboundRtpStreamStats, last: InputAudio): Promise<InputAudio> {
         const bitrate = calculateRate(entry.timestamp, entry.bytesReceived, last?.timestamp, last?.totalBytesReceived);
         const packetRate = calculateRate(entry.timestamp, entry.packetsReceived, last?.timestamp, last?.totalPacketsReceived);
-        const packetLossRatio = calculatePacketsLostRatio(entry.packetsLost, entry.packetsReceived, last?.totalPacketsReceived, last?.totalPacketsLost);
+        const packetLossRatio = calculatePacketsLostRatio(entry.packetsLost, entry.packetsReceived, last?.totalPacketsLost, last?.totalPacketsReceived);
         const packetLossDelta = (entry.packetsLost ?? 0) - (last?.totalPacketsLost ?? 0);
         const codec = this.#getCodec(rtcStatsReport, entry.codecId);
 

src/webRTCStats.ts

@@ -58,9 +58,16 @@ describe('utils test suite', () => {
     });
 
     test('calculatePacketsLostRatio', () => {
-        expect(calculatePacketsLostRatio(100, 0)).toEqual(0);
-        expect(calculatePacketsLostRatio(100, 200)).toEqual(0.5);
-        expect(calculatePacketsLostRatio(100, 200, 50)).toEqual(0.25);
-        expect(calculatePacketsLostRatio(100, 200, 50, 100)).toEqual(0.5);
+        expect(calculatePacketsLostRatio(100, 0)).toEqual(1);
+        expect(calculatePacketsLostRatio(0, 1)).toEqual(0);
+
+        expect(calculatePacketsLostRatio(100, 300)).toEqual(0.25);
+        expect(calculatePacketsLostRatio(150, 100, 50)).toEqual(0.5);
+        expect(calculatePacketsLostRatio(150, 200, 50, 100)).toEqual(0.5);
+
+        // corner cases
+        expect(calculatePacketsLostRatio(0, 0, 0, 0)).toEqual(0);
+        expect(calculatePacketsLostRatio(100, 100, 100, 100)).toEqual(0);
+        expect(calculatePacketsLostRatio(0, 0)).toEqual(0);
     });
 });