What equipment do I need to do a Live stream?

Part 1. - The basics

1. Internet connection

Your internet upload speed* should be 2.5x the bitrate you choose to broadcast at. Note: this is only a guideline, however attempting to broadcast at too high a rate for your connection may result in poor performance of your stream.

2. An Encoding PC

The PC you choose to use as your Encoder should use the following guidelines:

-         Pentium 4 Processor running at 2.4 Ghz or higher
-         512 Mb of Ram for audio, 1 GB of Ram for video
-         Windows XP-         Windows Media Encoder 9

Note: other configurations will work, although this is a good basis to work from when selecting a PC.

3. A source

Your Live broadcast can come from a camera or microphone attached directly to your encoder, a video or audio mixing board, or a file.

Note: the quality of broadcast you can send out is directly proportionate to the quality of input into your encoder; use the best possible equipment and wiring, or the best quality file, to get the best broadcast.

* Below is a link to a popular speed test site which has test points located all over the globe.  All you will need to run this test is a java applet (which they will have you download if you don’t already have it installed).  It’s as easy as installing the applet then clicking the start test button.

Here is the link to the test site…

http://www.broadbandreports.com/speedtest?more=1

Simply select a test location nearest to you and then follow the directions.  The number that you will be interested in is the Kbps number, this will give you a basic idea of what your connection can handle.  The typical DSL connection has around 2044 kbps down and 768 up.

Part 2a. - The details

Internet connection

Here is a breakdown of the different types of internet connections available. When selecting an internet connection type, remember that you will want 2.5x the upload speed as your chosen bitrate. Note: Not all connection types are available in all areas, check with your local ISPs to confirm availability.

Carrier Technology
 Description
 Speed
 Suitable for streaming?
 
Dial-up Access
 On demand access using a modem and regular telephone line (POT).
 2400 bps to 56 Kbps
 Generally not suitable
 
ISDN
 Dedicated telephone line and router required.
 64 Kbps to 128 Kbps
 Generally suitable for audio broadcasts
 
Cable
 Special cable modem and cable line required.
 512 Kbps to 20 Mbps
 Generally suitable for audio or video broadcasting
 
ADSL/DSL

Asymmetric Digital Subscriber Line
 This technology uses the unused digital portion of a regular copper telephone line to transmit and receive information.
 128 Kbps to 8 Mbps
 Generally suitable, however upload speed varies. Check with your local ISP to determine your actual upload speed.
 
Wireless (LMCS)
 Access is gained by connection to a high speed cellular like local multi-point communications system (LMCS) network via wireless transmitter/receiver.
 30 Mbps or more
 Generally suitable, but not available or reliable in all areas.
 
Satellite
 Newer versions have two-way satellite access, removing need for phone line.
 6 Mbps or more
 Suitable for streaming, generally used when other connection types are not available.
 
Fractional T1
 Only a portion of the 23 channels available in a T1 line is actually used.
 64 Kbps to 1.544 Mbps
 Generally suitable.
 
T1
 Special lines and equipment (DSU/CSU and router) required.
 1.544 Mbps
 Generally suitable for all broadcasts, possibly excluding very high bitrate streams.
 
T3
 Typically used for ISP to Internet infrastructure.
 44.736 Mbps
 Suitable for all streams, generally used only by large corporations/agencies.
 
OC-1
 Typically used for ISP to Internet infrastructure within Internet infrastructure.
 51.84 Mbps
 Suitable for all streams, generally used only by large corporations/agencies.
 
OC-3
 Typically used for large company backbone or Internet backbone.
 155.52 Mbps
 Suitable for all streams, generally used only by large corporations/agencies.
 

Part 2b. - The details

There are two primary methods for encoding video:

Capturing and encoding from a live stream directly to a Windows Media broadcast as a real time process.

Capturing to an uncompressed AVI file, and then encoding a Windows Media file from the AVI file in non-real time.

Live event broadcasting requires real-time encoding. Two-step or two-pass (note: these are not the same) encoding is generally used for creating OnDemand content.

There are also several items you need to consider when building a high quality workstation:

Source quality.

The final product can be no better than the source. Make sure to use as high a quality digital input format as possible. With the proper digital interface, such as the IEEE 1394 (sometimes called FireWire) interface or the professional Serial Digital Interface (SDI), you can skip the analog-to-digital conversion that reduces quality. If you must convert from analog, make sure your video source is high quality, and use S-Video connectors if possible.

If you are capturing from a tuner, demodulator, film scanner, mixing board, or router, make sure the cables and connections are professional quality and working properly, and the radio frequency (RF) connections to the tuner or demodulator are properly adjusted and terminated. Not only does poor source quality result in a poor quality product, any noise, glitches, or instability in the picture can increase the bit rate and size of the final file.

Fast CPU, PCI bus, and more RAM.

A fast CPU enables a computer to keep up with the demand imposed by the continuous stream of bits, while a fast PCI bus moves those bits easily between the capture device and the processor. A large amount of RAM eases the load on the CPU by enabling bits to be cached as they are converted. If your CPU usage often hits 100 percent, there is a very good chance the capture quality will be impaired. If necessary, use a computer with dual PCI buses to improve performance.

High-quality capture cards.

A capture card is responsible for properly inputting and processing the audio and video signals, and then converting them into a digital stream of bits. For this reason, the video capture card is the most important link in the chain. A low-quality or outdated capture card can greatly reduce the quality of the video. After the video has been converted to digital form, the data can be stored, transferred, and copied without affecting quality.