First draft of AES67 RTP timestamp analyzer tool. Prints RTP to PTP timestamp difference min/avg/max in console

ptpanalyzer.js

const dgram = require('dgram');
const chalk = require('chalk');
const ptpv2 = require('ptpv2');

let interface = '10.0.0.12';
//let multicastAddr = '239.69.161.58';
let multicastAddr = '239.69.80.114';
let samplerate = 48000;
let client = dgram.createSocket({ type: 'udp4', reuseAddr: true });

let total = 0;
let count = 0;
let min = 100000;
let max = -100000;
let seqErrors = 0;
let tsErrors = 0;

let prevTimestamp = 0;
let prevSeqNum = 0;

client.on('listening', function() {
	client.addMembership(multicastAddr, interface);
});

client.on('message', function(buffer, remote) {
	let ptpTime = ptpv2.ptp_time();
	let timestampCalc = ((ptpTime[0] * samplerate) + Math.round((ptpTime[1] * samplerate) / 1000000000)) % 0x100000000;
	let timestampBuffer = buffer.readUInt32BE(4);
	let seqNum = buffer.readUInt16BE(2);
	let diff = timestampCalc - timestampBuffer;
	total += diff;

	if(diff < min){
		min = diff;
	}

	if(diff > max){
		max = diff;
	}

	if(seqNum != ((prevSeqNum + 1) % 0x10000)){
		seqErrors++;
	}

	if(timestampBuffer != prevTimestamp + 48){
		tsErrors++;
	}

	prevSeqNum = seqNum;
	prevTimestamp = timestampBuffer;

	count++;
});


ptpv2.init(interface, 0, function(){
	client.bind(5004);
});

setInterval(function(){	
	if(count != 0){
		var avg = Math.round(total / count * 100) / 100;
		var diff = max - min;
		var diffMS = Math.round(diff / 48 * 1000) / 1000;


		var minStr = (Math.round(min / 48 * 1000) / 1000)+'ms';
		var maxStr = (Math.round(max / 48 * 1000) / 1000)+'ms';
		var avgStr = (Math.round(avg / 48 * 1000) / 1000)+'ms';

		if(diff > 2*48){
			console.log(chalk.red('min/avg/max (diff) =', minStr+'/'+avgStr+'/'+maxStr+' ('+diffMS+'ms)'));
		}else if(max > 2*48 || min < 0){
			console.log(chalk.yellow('min/avg/max (diff) =', minStr+'/'+avgStr+'/'+maxStr+' ('+diffMS+'ms)'));
		}else{
			console.log(chalk.green('min/avg/max (diff) =', minStr+'/'+avgStr+'/'+maxStr+' ('+diffMS+'ms)'));
		}
	}else{
		console.log('0 packets received, RTP stream not running');
	}

	if(seqErrors + tsErrors  > 0){
		console.log(chalk.red('seq/ts errors = '+seqErrors+' / '+tsErrors));
	}
	
	total = 0;
	count = 0;
	min = 100000;
	max = -100000;
	seqErrors = 0;
	tsErrors = 0;
}, 1000);