The Basics

What is the TVU Broadcast application?

TVU’s free Broadcast application is designed to allow anyone with a PC (Windows or Linux) and a broadband internet connection to create their own TV channel.  TVU’s goal in releasing this software is to democratize broadcasting – enabling existing TV channels to find a global audience, and allowing you to create new channels that mirror your interests.  We hope that you’ll create unique channels that are educational, cultural, and most of all, just plain fun.  We’d love to see surfing channels, high school sports channels, great webcams, and things we never even thought of. 

Is broadcasting on TVU free?

Yes it is.  TVU sells broadcast hardware and services to professional broadcasters, but for amateur broadcasters using the downloadable software, there are no charges for broadcasting on TVU.

What is TVU’s content policy?

First, TVU respects the rights of copyright holders.   As a broadcaster, you affirm that you have the legal right to broadcast the material you show on TVU.  Second, we ask that you not broadcast any “adult” content.  If you break these rules, TVU may shut down your channel without any notice.

What do I need to become a TVU broadcaster?

To become a broadcaster, you’ll need a PC running Windows (2000, XP, or 2003 Server; with IE 6.0) or Linux, and a broadband Internet connection.  You’ll need to download the TVU Broadcast application, and fill out an application for your channel.  In this process, you’ll create a broadcaster account (ID/password), and TVU will assign you a Channel ID.  You’ll probably also need a piece of add-on hardware to get video into your PC, and a third-party media encoder program – see below.

Can you explain the basic broadcasting process?

- First, you’ll need to make the media (video and/or audio) that you want to broadcast available to your PC.  If it’s already there, in the form of files, or if it’s in the form of a stream that’s available over the Internet, then you’re OK.  If not, you’ll usually need a hardware add-on, either an external device that connects to your PC via FireWire or USB 2.0, or an internal capture card.  Your video source will plug into that device.

- Second, you’ll probably have to “encode” the files or the video source into the format (Windows Media Video, or WMV for short) that the TVU Broadcast application recognizes.  You can do this with third-party “media encoder” software that’s freely downloadable on the Internet.  If you’re re-broadcasting a stream from the Internet, you won’t need to do this if the source is already in WMV format.  If you’re broadcasting from files, and they’re not already in WMV format, we recommend encoding them ahead of time.  If you’re broadcasting from a live video source (i.e. video coming in over a hardware device, as discussed above), you’ll be encoding in real time, i.e. running both the encoder program and the TVU Broadcast application at the same time.

- Third, you use the TVU Broadcast application to broadcast your encoded signal out to the TVU network.

Technical Details

Which operating systems does the TVU Broadcast application support?

We have two versions of the Broadcast application that you can download:  one for Windows (2000, XP, or 2003 Server), and one for Linux.  If you’re running a Windows PC, you should also have Internet Explorer (IE) version 6.0 or above.

How powerful does my PC need to be?

The TVU Broadcast application is not very demanding, however the media encoders are very processor-intensive.  So if you’re encoding and broadcasting live video, you’ll want a fairly powerful PC.  Power needs will go up with signal bandwidth and the quality of the image (see the signal bandwidth discussion below).  The absolute minimum we’d recommend is a 1GHz processor and 128MB of RAM. If the encoding is done on the same machine, then the recommended Windows PC would have a dual core processor running at 1GHz or more and at least 512MB of RAM.  For best results (highest video quality), we recommend a dual core processor running at 2.4GHz or more.  PCs running Linux will not need to be quite as powerful as Windows PCs.  If your encoder program “hangs” while you’re broadcasting a live video signal, we suggest you try a lower signal bandwidth because your PC may not be powerful enough to encode your signal in real time.

How much Internet bandwidth do I need to broadcast my channel?

What matters for broadcasting is the “upload” speed of your Internet connection.  We recommend that your upload speed be a minimum of 2x the signal bandwidth (see the signal bandwidth discussion below) you decide to use for your channel.  We recommend 4x, and 10x will give the best results (best viewer experience).  So for example, if you use a signal bandwidth of 120Kbps, you’d need a minimum of 240Kbps of upload speed, with 480Kbps as the recommended speed, and 1.2Mbps as the optimum speed.  If you don’t have enough upload bandwidth, users will tend to have a bad experience viewing your channel, for example long start-up times and frequent “glitches” in the signal.

What signal bandwidth should I use for my channel?

The TVU technology allows the use of any signal bandwidth.  Practically speaking, though, since TVU is a peer-to-peer (P2P) based system, it’s important to consider what upload bandwidth your viewers will have available.  The average upload bandwidth of your viewers needs to be greater than or equal to the signal bandwidth you choose.  Our experience is that the average TVU viewer has an upload bandwidth of 300-350 Kbps, and therefore most TVU channels fall in that range.  Some TVU channels (mostly marked with a “(low)” in their name in the Channels list) use a lower bandwidth of about 120 Kbps.  Since you, as the originating broadcaster, will need multiples (2x minimum, 4x recommended, 10x ideal) of your signal bandwidth, your own upload speed may also limit your choices.  If your encoder program “hangs” while you’re broadcasting a live video signal, we suggest you try a lower signal bandwidth because your PC may not be powerful enough to encode your signal in real time.

A typical standard-bandwidth TVU channel uses 289Kbps for video, at a size of 320x240 and a frame rate of 30 frames per second (fps), and 32Kbps for audio.  A typical low-bandwidth TVU channel uses 101Kbps for video, at a size of 320x240 and 15 fps, and 16Kbps for audio.  The choice is yours – pick any combination that you feel will work well for your channel, given the PC power and upload bandwidth that you have available.

Which media encoders does TVU recommend?

For Windows, we recommend either Microsoft’s Windows Media Encoder (WME), version 9 or above, or the freeware VideoLAN Client (VLC).  WME is easier to use if you’re new to PC video.  For Linux, we recommend VLC.  Both can be downloaded for free on the Internet.

What media format does TVU require?

For maximum compatibility, TVU requires the use of the Windows Media Video (WMV; *.wmv for files) format.

What is the “Media URL” in the TVU Broadcast application?

This is how you tell the Broadcast application what to broadcast – the URL is the address of the stream that will be broadcast.  If you’re re-broadcasting a stream available on the Internet, simply enter its URL here.  If you’re encoding the video/audio as you broadcast it, this URL is used to communicate between you and the encoder; the URL you enter should match what you’ve set the encoder to.

What is the “Port” in the TVU Broadcast application?

This is the port through which you’re broadcasting to the outside world.  The Broadcast application selects a port for you, which you can override if you want.  The Broadcast application should be able to get through your firewall, if you have one. However, we recommend that if you’re using a firewall, you open the port to get the best results from the application.  If you do this, you’ll want to use the same port number every time you start up the Broadcast application.  Consult your firewall manual for information on how to open ports.

What is QS?

QS stands for Quality of Source Stream. It usually should be above 90%, if your media encoder is on your local machine.

What is QC?

QC stands for Quality of Channel. It is a good idea to keep it above 75%.

How can I improve QC?

1) Make sure that your stream bit rate is less than half of your upload bandwidth.
2) Stop any program which may consume your upload bandwidth, such as file sharing software or TVUPlayer

Can you give me an example of how to broadcast live video?

Assuming you’ve already connected up your video source and downloaded the encoder (Windows Media Encoder 9 in this example), here’s an example of live broadcasting:

1) Start up WME (it’s the application called “wmenc” in the Program Files\Windows Media Components\Encoder folder); 

2) Click the “New Session” button;

3) Select the “Broadcast a live event” wizard;

4) In the Device Options page, tell WME what video and audio source to use;

5) Select “Pull from the Encoder” in the Broadcast Methods page;

6) In the Broadcast Connection page, select a port (this is a port that will be used internally to communicate with the Broadcast application; it’s NOT the same as the port referred to in the Broadcast application, which is used between the Broadcast application and the outside world) and write down the URL shown as “URL for Internet connections” (you’ll need it in a minute);

7) Select your signal bandwidth in the Encoding Options page (see the “signal bandwidth” section above);

8) Press “Finish”.  Now you’ve got the encoder running and you’re ready to broadcast.  9) Open the TVU Broadcast application, log in, enter the URL from step #6 above and your Channel ID (which TVU assigned to you when you applied for the channel), pick a Port (you should be able to use the one that the application picks for you), and press “Start”.  That’s it - you’re broadcasting!