Live streaming

1) QuickTime Broadcaster is a stand-alone application that is used to stream live material. It can stream, audio, or video, or both. Quicktime Broadcaster is only supported by Mac OSX/Server v10.1.5 or later AND PowerPC G3 or later. Normally, for live material, you would plug a video camera into MAC OSX through FireWire and use that as the input source. Broadcaster would then take that material, encode it, and stream it out. Broadcaster can either stream directly to the client (called unicasting, used for one-on-one presentation), or multicast it (used on a LAN). Multicasting works only on a LAN through a Multicast Backbone (MBONE) network and not on the internet. (For more information regarding MBONE, go to http://www.serpentine.com/~bos/tech/mbone/) If you want to stream video to one person on the net, you would use manual unicasting. If you want to stream video to more than one person over the net, this is where Darwin Streaming Server comes into play.

2) Darwin Streaming Server is the multicasting (sending to multiple users) aspect of a QuickTime streaming solution. It runs as a daemon in the background on Windows, as well as on a variety of UNIX environments (such as Linux and Solaris) and Mac OS X. In order to stream to multiple users on the net, QuickTime Broadcaster would unicast a stream to a streaming server and users would connect to the streaming server, rather than directly to QuickTime Broadcaster. There are two ways of unicasting a stream; manual, and automatic.

3) Manual unicasting involves exporting an SDP (session description protocol) file to the "Movies" folder of the streaming server (usually C:/Program Files/DarwinStreaming/Movies on Windows). You will need to set the audio, video and network settings on the Broadcaster before exporting the SDP file. To export the SDP file, simply click on File->Export->SDP and save it to a temporary file on your desktop. Then you just send/copy the file over to the movie folder mentioned above on the Darwin Streaming Server. The user would then access the streaming server in QuickTime Player using the URL "rtsp://myserver/mystream.sdp", replacing "myserver" with the IP or domain name of the streaming server and "mystream.sdp" with the name of the stream which is defined in QuickTime Broadcaster. To do this, simply click on File->Open URL in a new player and enter the URL above. (Note: The machine that Darwin Streaming Server is running on should not have VPN client running because the VPN Client will assign another IP address to the machine hence blocking the streaming of the video to other client computers as well as the receiving of the encoded stream from Quicktime Braodcaster.)

4) Automatic unicasting is easier than manual unicasting. Instead of generating an SDP file and placing it in the Movies directory, the user simply enters the IP address or domain name of the server, admin login and password for the streaming server. The SDP file is then automatically generated by the server, no extra configuration needed. This is useful because with manual unicasting, if you change settings then you have to re-export the SDP file and re-upload it to the streaming server Movies directory. Whether you use manual or automatic unicasting is transparent to the user, they simply access the stream using the rtsp:// URL from QuickTime Player.

On-demand streaming

5) For on-demand streaming of archived video files, you only need to put the video file into the “Movies” folder as mentioned. The user would then access the streaming server in QuickTime Player using the URL "rtsp://myserver/mystream.mp4", replacing "myserver" with the IP or domain name of the streaming server and "mystream.mp4" with the name of the movie which is to be viewed. (mp4 refers to MPEG4 movies, Darwin Streaming Server can stream many other video file types including MOV, MPEG1, MPEG2, etc)

Achieving almost real-time broadcasting

1) Almost real-time live broadcasting (less than 1 second)can be achieved by changing some settings at the Quicktime Broadcaster, Quicktime Streaming Server as well as the Quicktime Player.

2) Quicktime Player – go to Edit->Preferences->Quicktime Preference. Next choose Instant-On from the drop-down menu and set Play Streams to Immediate. With this, the Quicktime Player will play the incoming video stream immediately and not keep a buffer.

3) Quicktime Broadcaster – click Show Details and click on the Networks panel. Set buffer to zero to enable the Quicktime Broadcaster to send out the video stream immediately after compression.

4) Darwin Streaming Server – set the “reflector_buffer_size_sec” property in the streamingserver.xml in the Darwin Streaming Server to be zero which was previously set to 10.

5) Whatever delay that is now visible will just be the networking delay.

( Tutorial edited from jonoid//weblog http://projectprime.com/~jonoid/weblog/archives/000144.html )

Darwin Streaming Server is supported by various Operating Systems such as MAC, Linux FreeBSD and Windows 2000/NT/XP. The following tutorial details the installation of the Darwin Streaming Server on a Windows 2000/NT system. The Darwin Streaming Server for Windows OS can be downloaded from okayama/kogepan/Farzam/Darwin_video Streaming. The file to be downloaded is DarwinStreamingSrvr4.1.3-Windows.exe.