Streaming Overview

Streaming refers to sending audio and/or video from your computer to a server that is running a streaming program like Shoutcast, Icecast, Windows Media Server, Quicktime, or Helix..  Those programs then make that audio or video available for remote listeners.  Worldbridges currently uses Shoutcast to stream its webcasts.  Depending on audio bitrate and other variables, there is usually a delay ranging from 20-100 seconds between the time the audio is produced and the time it is heard by remote listeners.  

Producing a stream of audio with only one source of audio (music or one person speaking) is relatively simple.  Producing a a stream of audio in which multiple sources are streamed (i.e. a multi-person conversation) is more complicated and requires the tools and methods covered in the 'Recording both ends of a telephony call' section of this book.   While it is possible to record both sides of a telephony call using 3rd party programs like Powergramo and Pamela (more info here) we have thusfar been unable to use those tools to actually stream. The tools used to stream vary significantly by operating system. Below are pages that deal with streaming on different operating systems.

Streaming (webcasting) with Linux

Linux for WebCastAcademy Interns
by   Minhaaj ur Rehman

Hi, My name is Minhaaj and I am a new webcastacademy intern. My primary OS is Ubuntu, linux and this is what I use to participate in this fabulous community. When I joined the community, I found that no one used linux (to my knowledge) linux for participation and I was the first one who had to figure out things mostly by myself. I would like to appreciate help of Jeff, Doug, Sheila and rest of the webcastacademy guys who helped me out in figuring the configurations for linux.

I am writing this tutorial in response to popular community request for a how-to tutorial for using webcastacademy on linux. If you are intern your first assignment would be to introduce yourself. You can use variety of tools for that, e.g. audacity. What I used on linux was a program called sound recorder. It has a plain and sleek interface with a very basic function ‘to record the sound’ :) That’s what it does and it is designed to do. No less and no more. Although a format conversion would have been nice. Good news is that you can record sound in different formats, wav, ogg, mp3, FLAC etc. So its kind of a relief to know that.

Thats how program's interface looks. You see that Red record button? All you have to do is to select the required output format and hit that button and start your Skype call or whatever medium you are using for conversation. As far as input method is concerned, I didn't have to figure that out, because by default mine is set to Digital. If you can't it to work you probably need to fix your sound settings. I believe there are numerous tutorial online on Linux forums and other places and I really can't recommend one because it depends on what problems you are having specifically. Make sure your sound is working normally and your OS has recognized your Microphone.

Next steps are pretty straight forward since they are same on all operating systems. You have to log into webcastacademy's interns account. If you are an intern you probably know the login and password that Jeff and Doug have told you. If not, I suggest you should sign up for internship and join this fabulous community asap :) This is how screen would look once you have the username and password and you are ready to broadcast. Remember you don't need Ustream for recording your first assignment thats introduction and even your second one thats, recording a two-way Skype call. You can use it but I guess offline tools are better for first two, but again, feel free to try. My problem had been file conversion.

You need Ustream primarily for broadcasting and thats the third assignment, so until then get used to your computer softwares. :)

Make sure you are already in call and click the orange 'BROADCAST NOW' button on top, before the search box. Once you have clicked the button another screen would pop up that would start loading the broadcasting screen. Let it load until it stops. Notice that during the loading process, a popup would appear that would request you to allow audio and video control of your computer. You should allow that by clicking the green button with 'allow' written on it. This is how your new screen would look like.

Press Allow and screen would change into this one:

Now you have to make sure you are in the call. There are two green buttons. One says 'Start Broadcasting' and other says 'Start Recording'. If you are using sound recorder for recording you probably don't need that and you can ignore 'Start Recording'. I would highly recommend that you use 'Start Recording' so that if anything goes wrong, community can help you with that. I had a problem with format conversion and Sheila came to rescue me.

And, ofcourse you have to press 'Start Broadcasting'. No Brainer. Once you are done with that, you are good to go. You should mute the streaming audio/video on webcastacademy or Edtechtalk page where ever you are to make sure that you don't hear your own voice. Keep switching windows to make sure you are using text chat too, because you might get consumed by Skype chat, which one often does that you forget that you are doing the show for people :)

Use forums for any problem that you encounter.  You can ask Jeff, Doug and ofcourse Me anytime you find me around. My Skype name is Minhaaj.Rehman.

Streaming (webcasting) with Windows

Basic Streaming with Windows

There are a number of programs that can be used to stream to a Shoutcast server from windows.
These include:

Relevant Screencasts

Other Resources


Checklist for Audio Setup to Webcast in Windows: Streaming

Jeff's Screencast on this

First part is just like for recording. If you aren't recording, skip opening Audacity, but do the rest...
_ Set up audio settings in Windows (right click on speaker icon at lower right of screen)
_ Open Volume Controls
_ Options; Properties
_ Select Recording (make sure that Mixer Device is sound card); OK
_ Select Stereo Mix check box and close
_ Plug in USB If you are not recording, you can skip the next two steps
_ Open Audacity;
    _ Pull-down menu input device s/b Stereo Mix
    _ NOW open audio repeater
_ Click STOP button to adjust settings
_ Set Wave in to AK5370
_ Set Wave out to sound card
_ Set Total Buffers to 100
_ Set BPS 22 or 24
_ Buffers 16
_ Channels Stereo/2
_ Priority High
_ You may want to wait to start...
_ Volume control for mic setup
_ Select Properties
_ Select AK5370/USB mic as device on Playback and you will get a volume control for that device.
This is where you are setting up for streaming
_ Check out this to get info on links, logins for Sandbox
_ Login to ShoutCast; this will tell you if anyone is on
_ Get on Listen Page (this could be done later--I like it out of the way)
_ Open up SimpleCast; click start
_ If it is the first time, set up encoders click on ENCODERS button
_ Click on + to add encoder
_ Converter Tab
_ MP3; 64kps @ 44100 or 22050
_ ShoutCast; Server details here; give it a name
_ Stream archive (this will create a raw audio)
_ Click okay
_ Make sure that Audio Repeater has started
_ Start recording in Audacity
_ Click Start triangle on Encoders page and you will be streaming
_ Go to the Listen Page refresh, and you should see stream. Click on play to confirm you are streaming.
_ When you are done, click on stop in encoder and Audacity and power off in SimpleCast
_ Save Audacity as MP3 look for raw audio stream and you are ready to edit


Using Sandbox

Streaming (webcasting) with a Mac



NiceCast - Mac

At this point, Nicecast is the only piece of streaming software for a Mac that we've found capable of producing live interactive webcasts. Learn lots more and download a free demo at the t Nicecast Homepage at

"About Nicecast" Video (from

How to Webcast  and troubleshoot audio problems in Nicecast (by Lee Baber)
-- Here is an additional note about audio settings in Nicecast. This is a blog comment I made to a post concerning this issue. 

Possible audio issues with Nicecast

Often when I click broadcast and then Skype is hijacked, I have no sound, in other words, I can hear the tone that Skype has started but when I talk, my meter in Nicecast does not move and I do not have an echo. I am not broadcasting. I now know to check first that the audio device is selected. Even if it was selected, it appears that when Skype launches (is hijacked) Nicecast looses the audio device that you have carefully chosen when you first opened it.

I've been thinking that it's a conflict and trash the skype preference in the library of the root user but then the whole computer needs to be restarted. Worse yet, sometimes that seems to not resolve the problem. Well, now I realize that it is not even the problem - just make sure that your audio device is still selected! Thank you Lee!

Simulcast with Eluminate on a Mac with Nicecast

During the WEBheads in Action Convergence I was able to simulcast Barbara Ganley who was presenting in Eluminate. I made my way to Eluminate and logged in. Then I opened Nicecast and set it to the correct server at WB. Then in Nicecast, for Source I selected Application, found Eluminate LIVE, then went to ADVANCED and selected system output, instead of default, that means that I am streaming the regular system output, not speakers, no mic etc.

Then jump over to the editor, select from the desktop the java. For me it was called meeting-jnlp, when I clicked on that it came up as Java cache viewer. Then I started the broadcast, saw that it was ON AIR, then went back to editor and hijacked. The strange thing is that the number counter doesn't move. Well, I think that is because it is not recording anywhere,  just streaming.

All for now.

May 18, 2007

Cheryl Oakes 


Streaming on two channels with NiceCast

After going through the Simplecast screencast and learning how to stream on both Sandbox A and B at different levels, I returned to NiceCast and was baffled how to do it on Mac. I wrote to Rogue Amoeba Software Support on Lee's suggestion. Here is my question and their answer:

Question: In Simplecast or SAM on my XP machine, I can broadcast using on two channels, one for people with higher bandwidth and one for people with lower bandwidth. In Nicecast, I can set up the different channels as different servers, but I don't see how to broadcast on two at once and how to do it with different quality settings????

Answer: Unfortunately, Nicecast does not support simultaneous broadcast of two streams as of yet. Maybe in the future.

The dreaded echo in Nicecast!

The dreaded echo! While streaming and using Nicecast and Skype, I would experience an echo chamber and I would have to delay my speaking. I checked my system preferences, the microphone was selected. I checked SKYPE and the microphone was selected. I checked Nicecast and the microphone was selected! However, I still had the echo. Then just by chance I checked effects in Nicecast, then editor, then advanced and viola, the hijack had mysteriously taken over and hijacked  all audio streams instead of one audio stream. As soon as I checked that back to select one audio stream, I've been good!

At the end of a 75 min. show, I begin to hear a little echo, but I believe that is just my intel imac and skype dualing.


Good luck.

Cheryl Oakes


PS  The audio stream for the most part still is usable. 

Nicecast Set-up Screencast

 Nicecast Screencast and Skype Preferences Screencast

This screencast has no sound. Hopefully you will be able to follow the steps to set up your Nicecast to record both ends of a conversation now. Do not forget to go to Skype > Preferences and make sure you choose the proper audio source before you begin. Let me know if you have any problems at all. ~Lee

Mac Webcasting Set Up for Nicecast

Set Up - also see Screencasts at bottom of page

For USB mic:

1) Plug the microphone and headphones in, then launch Nicecast and Skype.
2) In Nicecast's Source drawer, set the first pop-up to Audio Device and then select your microphone for the Input Source. This should be the same device selected in Skype's Audio preferences for Input.
3) Next, open the Effects window, and insert the Application Mixer plugin.
4) You need to adjust the Application Mixer's settings, in the Editor window. Set Skype as the Application, and leave the Crossfade at 50%. Click Advanced... and set it to Hijack One Audio Stream (Default). This must not be set to MegaMix, or your audio will come through twice causing major echo.
5) Finally, press the Start Broadcast button in Nicecast.  Audio from your microphone will be broadcast. When you click Hijack in the Application Mixer plugin, audio from Skype will also be brought in.

The audio from your microphone is going two places, into Skype and also into Nicecast. In Skype, this audio is sent to the person to whom you're speaking. In Nicecast, this audio is mixed with the audio pulled from Skype, specifically the other speaker's portion of the conversation. This is combined together to make one audio stream of the conversation.


Now that you are set as described above, you should  hear both sides of the conversation and be set to go.  Speak using the microphone, and accept calls through Skype or start a conference call in Skype and add as many as your Skype version or computer can handle. You can also play any audio that is in iTunes, and grab that with a second instance of the Application Mixer plugin. 


For USB headsets:

1) Plug the headsets in, then launch Nicecast and Skype.
2) In Nicecast's Source drawer, set the first pop-up to Application and then select Skype.
3) Next, click on Advanced.
4) You need to select MegaMix in the Advanced window, not Hijack One Audio Stream
5) Finally, press the Start Broadcast button in Nicecast.  Audio from your headset will be broadcast. 


Now that you are set as described above, you should hear both sides of the conversation and be set to go.  Speak using the headset's microphone, and accept calls through Skype or start a conference call in Skype and add as many as your Skype version or computer can handle.

Relevant Screencasts:



Image icon headsetpic.png138.76 KB

Webcaster Access Info

Stream Access 

Sandbox A
Port: 8000

Sandbox B
Port: 8002

Interns are welcome to use the Webcast Academy Ustream account by logging in at

ID: webcastacademy
Password: Same as above

Chat Logs

Chatlogs are mailed to [email protected]  everyday around 0600GMT .  Password is standard password for this session.

Audio Specifications

Bitrate: 64kbs
Sample rate: 22 or 44khz (required for audio posted with audio module)
File names:  ShowCodeEpisode#-yyyy-mm-dd.mp3 (i.e. EdTechTalk75-2006-12-18.mp3 , Teachers38-2007-01-31.mp3)
ID3 Tags: Include at least Show Title, License, URL
Streaming: If possible stream hi bitrate (64kbs) to EdTechTalk A, and lo bitrate (24kbs) to EdTechTalk B.  If bandwidth is limited, only stream to EdTechTalk A.

Posting Specifications

Posting to the calendar:  (Method changed Dec. 2007)  We now use Google  Calendars to post events.   You can log in to the [email protected] account (password is the same as Sandox passwords) and click calendar/ create event to add an event.  The time zone for this gmail account is GMT/UTC.   You can also click 'manage calendars' / Shared/Edit Settings, and add your gmail address to the share list.  You can then post in your own time zone.  (Stay tuned for Screencast)

Show recordings can be posted as an audio node (create content/ audio).  Body of post can include show name & #, date,  descriptive blurb, and/or  chat log.   To determine with the teaser ends on the front page, go to html mode by clicking the 'toggle html source' icon above and enter <!--break-->


Webcasters can setup their own teleconference and include that in a webcast.  There are number of sites that provide this service for free, including and