Sunday 26 February 2012

Setting Up a Live Broadcast on the Internet

By Geoff Leff

Broadcasting live content over the Internet isn't as difficult as people would think. In fact, it's extremely easy. All you need is an audio or video source, a way of getting the audio or video to the PC, a free software program supplied by Microsoft, and enough upload bandwidth to cover the broadcasting of the content.

In this tutorial, I'll attempt to teach you what you need to know so you can broadcast your content over the Internet. I'll primarily show you audio only, but you'll see how easy it is to do video as you progress through this tutorial.

As this is a text only tutorial, you will want to download the free software from Microsoft, and go through the configuration while you read this tutorial. Don't panic though. It's really easy to do. Don't let the length of this tutorial scare you away. The rewards of having your live broadcast up and running should keep you motivated to stick with it.

The only slightly complicated part of this tutorial is to do with your firewall. Due to the number of firewalls out there, I'll be very generic in my approach to telling you what you need to do. I'll explain this in further detail later in the tutorial.

Let's Start

First things first. You need to set up your audio source. In this example I'm using a radio scanner to broadcast Live Police from a radio scanner.

I basically have the radio scanner plugged into my PC's sound card with a cable roughly 2 metres (7 Feet) in length with a 3.5mm mono plug on each end. Of course the length of cable is up to you. Note: if you are broadcasting music, you'll want to use a cable that has stereo plugs instead of mono plugs. You'll also want to ensure your plugs on the cable match the audio device, Some devices may use a 2.5mm plug instead of 3.5mm. If you are broadcasting voice only, mono plugs are better as it ensures sound comes out of both speakers for the listener.

Plug the cable in so that one end plugs into the headphone socket of your audio device, and the other end plugs into the Microphone socket of your sound card on your PC.

Now go to the Microsoft website and download the Windows Media Encoder 9 software. It's free. It's approximately 9.5MB. The link to the software is located at the bottom of this article.

Once you've installed the software, go ahead and start it. You'll be presented with the setup wizard. Highlight the option named Broadcast a Live Event and click OK.

You'll now be in the window where you can choose your audio source and/or video source. If you were setting up video, you would leave both items ticked, however in this example, we're just going to do audio so go ahead and untick the video option. Under the audio option use the drop down box and choose your sound card from the list. Then click the configure button.

In the audio properties window the only thing you really need to change is the option called Pin Line. In the Drop down box, choose Microphone. Of course you can also use Line In, but you need to ensure you've plugged the cable into the Line In of your sound card.

So far it's pretty easy right? Believe it or not, there's not a great deal more to do.

Let's continue shall we

Just click OK and then Next.

If you've followed the tutorial so far, you should be in a window where you can choose a broadcast method. Click on the radio box next to Pull from the encoder and click on the Next button.

In the field labeled Http Port, pick a common port like 8080. You'll thank me later. Many firewalls on routers have rules already set up for port 8080 and it makes it a lot easier to configure. It also allows maximum availability to the masses due to it being a common proxy port number. Go ahead and click Next.

Next we need to configure the encoding options. Go to the drop down box and choose Multiple Bit Rates audio (CBR). In the Bit rate section, choose 19kb/s. Note: Ensure you untick all the other bit rates. The only bit rate you want ticked is 19kb/s. This bit rate should be a good compromise between quality and bandwidth consumption for streaming voice quality. If you want to stream something like music, you may want to choose a higher bit rate. MP3 audio tends to be around 128kb/s but remember the higher bit rate you use, the more upload bandwidth will be required.

For an idea of bandwidth usage, you can have roughly 40 concurrent listeners on a 1mb/s upload bandwidth using 19kb/s. This will leave you with about 250kb/s for doing other things on the internet. The more concurrent listeners you have, the more powerful CPU you'll require, but from experience, you don't need a high powered CPU. The Live Police scanner at my website has a maximum of 40 concurrent listeners on a 1.7GHz CPU with 1 gig of memory and runs beautifully. And yes, I have reached 40 concurrent users at once.

Let's continue

Click the Next button, and then click it again so we skip the Archive section.

Here we'll type in some text about the audio. When people listen to the stream using their Windows Media Player, it will scroll this information to the listener.

Once you've typed in the Display Information click the Finish button instead of the Next button. You'll get a pop up dialog box that tells you about IP blocking. Just ignore this for now and click OK.

That wasn't that hard was it. Believe it or not, we're done. Well, almost.

Windows Media Encoder only allows a maximum of 5 concurrent listeners by default, so if you want to have more than 5 you can make a small windows registry change on your PC which will allow up to 50 connections.

Warning: Changing the registry can be hazardous to your operating system if you change or delete the wrong thing. If you aren't confident doing this yourself, get someone that knows what they're doing to help you out. I can't be held responsible if you mess it up, and can't boot back into your operating system. Now, having said that, it's a very easy to make the change so you shouldn't have a problem. Follow the instructions at the end of this document, only if you want to allow more than 5 concurrent listeners. If you're happy with 5 listeners, then we're almost done.

If you've followed the tutorial up until now, you will have an audio source with a cable going from the headphone socket to the Microphone socket of your sound card in your PC. You will have your Windows Media Encoder totally configured and be raring to go. Just ensure you save the configuration on the Windows Media Encoder so you can load it at any time.

One more minor speed bump to get over and you'll be broadcasting to the world. This is the part that can be a little complicated though. I'll attempt to give you the basics you'll need to get your live broadcast up and running. We'll break this down into two parts. Configuring your firewall, and working out your IP address so you can give it out to your listeners.

Configuring your firewall

If you are using a software firewall such as Zone Alarm, it's dead simple to configure. Basically, you just run the Windows Media Encoder and click the Start Encoding button. When you do this your firewall should prompt you asking if you will allow the connections. Just choose YES to all the questions. It needs access to the Internet, as well as needs to run as a server.

If you have a hardware firewall such as one that is built into your ADSL modem/router, then it gets a little more complicated. What you need to do is go into the configuration of the modem/router, and find the section labeled Firewall. In that section you'll be able to configure firewall rules to either Allow and Deny connections. The section may be called something similar to packet filter. Consult your manual to find out exactly where you need to make the changes.

Once you've located the correct section, you'll need to configure it so that the source ports range from 0 to 65535. The destination port range should be 8080 to 8080 if you followed my tutorial. Ensure Inbound and Outbound traffic is also allowed.

Note, some modem/routers might already have port 8080 configured. If your modem/router does already have this configured, then ignore the above because it sounds like you're already configured to allow the necessary connections.

How to connect to the broadcast

The URL to give to people is mms://:8080 where is whatever your public IP address happens to be. You need to ensure it's the address your ISP gives you, since people from the Internet will be connecting to it. If you aren't sure what your IP address is, you can get your IP address by visiting a site on the internet such as http://whatismyipaddress.com. As soon as the site loads, your IP address will be at the top of the page in huge print. Simply replace with the actual IP address and your done.

Ensure you don't use the brackets in the URL though. It should look like mms://10.10.10.10:8080 except use your IP address.

That's it. I hope your head didn't explode

The only thing left to do now is adjust your audio source levels so that the audio meter stays mainly in the green. You can experiment by connecting to the stream yourself, and by putting the mms URL above into your browser's address bar and pressing enter. Your Windows Media Player should open and try and connect to the broadcast.

Note: If you aren't able to connect to the broadcast, only play with the firewall settings, and not the encoder. Ensure you have the START ENCODING button pressed on the encoder to ensure its running. If all has gone well, you should be listening to your broadcast over the Internet. Give that URL out to your visitors.

To increase the maximum number of direct connections

1. In Registry Editor, use the tree view to navigate to the following subkey:

HKEY_CLASSES_ROOTSoftwareMicrosoftWindows Media ToolsEncoderMaxClientConnections

2. Edit the subkey so that it reflects the maximum number of direct connections you want to allow. The maximum possible number is 50.

Caution Incorrectly editing the registry can severely damage your system. Before making changes to the registry, you should back up any valued data on the computer.

I hope you enjoyed this tutorial.
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