In order to choose the correct tool, you'll need to understand the basic types of NetShow content. NetShow tools take source information (either in live or stored form) and turn it into the Active Streaming format that NetShow Server can easily stream. Live information can be anything you can input into your audio or video card, including a CD player, microphone, VCR, or video camera. Stored information can be .avi, .mov, .wav, .jpg, or .bmp files. Once the media has been converted to Active Streaming format, you can deliver it to NetShow Server for streaming either as a stored .asf file or as a live ASF stream.
An ASF stream can be sent out over the network and received immediately. This means that a live event can be captured with a video camera, turned into an ASF stream, sent to a NetShow Server, and streamed over the network to various clients with minimal delay.
.Asf files serve as the storage place for ASF streams, but .asf files can also be .avi, .mov, or .wav files that have been converted for streaming. With certain tools, you can take audio and image files and arrange them along a time line for synchronized playback. This synchronized playback can also be saved as an .asf file. NetShow content can be anything from low-quality stored audio and image files to high-quality live video.
This content can be delivered via unicast or multicast. When NetShow Server receives a request from NetShow Player, establishes a direct link to a client, and then streams an .asf file to only that client, it is unicasting. NetShow Server can unicast many streams; the key to this is the fact that each stream takes up only part of the network bandwidth. When NetShow Server delivers a live ASF stream, it is multicasting. This stream is not directed to any one NetShow Player; instead any NetShow Player that knows where to look can listen in to the live ASF stream. NetShow Player is made aware of when and where the ASF stream will be by an active stream redirector (.asx) file, which can be sent via e-mail.
Having NetShow Server and the content tools is analogous to having your own regular and pay-per view television studio. The regular portion of your television studio multicasts ASF streams over the network. Anyone on the network with NetShow Player who wants to watch or listen to the content can do so. The pay-per-view portion of your television studio unicasts .asf files only to the NetShow Player that requested the file. When a viewer requests a particular file (an .asf file), NetShow Server makes a connection to that player, and streams the .asf file to that viewer and no one else.
With the NetShow tools provided here and the third-party tools available elsewhere, you can create .asf files from other types of stored media such as .wav, .bmp, .jpg, .mov, or .avi files. You can also mix and synchronize script commands into an .asf file. When users play back the .asf file, they will see the images and hear the audio the way that you intended. If you used script commands, those commands will be executed at the times you specified.
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