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QuickTime 4 introduced support for receiving real–time streamed data. That is to say, QuickTime–savvy applications can receive video, audio, and other kinds of data streamed across the Internet. Real–time streaming, unlike the progressive downloading of movie files that has been available since QuickTime 3, can handle live data and does not require downloading potentially huge files onto the user’s computer; this permits QuickTime playback applications to support uses such as video–on–demand and rebroadcast streaming.

The real–time streaming provided by QuickTime 4 was a client–side technology only; it did not provide any means to serve up, or transmit, the data streams. QuickTime 5 provides a set of broadcasting functions that allow us to create transmitter applications. For example, we can take the audiovisual data captured by a camcorder attached to one computer and broadcast that data to other computers on a network. Together, the transmitter technologies provided by QuickTime 5 and the receiver technologies provided by QuickTime 4 give us the complete set of tools we need to send audiovisual streams from one computer and view them on another. The good news here is that we need to know virtually nothing about the applicable IETF specifications to do all this; the really good news is that the amount of code we need to write to create a broadcasting application is surprisingly small. Indeed, we'll be able to write this application using fewer than a dozen of these new broadcasting functions.

The Real–Time Streaming Framework featured by the QTPlugin is a set of classes that allow developers to gain access to both the transmitter and receiver technologies provided by the QuickTime APIs within the Realbasic environment.

The QTPlgStreamSessionAudioParams utility class is part of the Real–Time Streaming Framework and is used to specify the characteristics of the audio streams that have to be sent or received from a .

Using this class requires QuickTime 4.0 or later.







The QTPlgStreamSessionAudioParams class constructors are called when you create a new instance of the class, while the ˜QTPlgStreamSessionAudioParams class destructor, is called automatically when the class is no more in use. Also, you can invoke the class destructor by setting the instance of the class to nil.

Once a new class instance is returned, it is good practice to check the class property to be sure that the new object can be used. An instance of this class is valid if the value of the property is not 0.


The class provides you with the following initializer methods:
()
This is the default constructor. Any class property is set to its default status; the default status forces a class instance to use the maximum values for both and properties and to disable
(other as QTPlgStreamSessionAudioParams)
This is the copy constructor. The properties of the object to be copied will be used to initialize the new class instance properties

returns the pointer to the QTSAudioParams structure in use. Useful for toolbox programmers; the client must not dispose of this pointer
determines the volume of stereophonic sound of a . You specify the left and right volumes by setting the and class properties respectively
determines the loudness of stereophonic sound of a . You specify the bass and treble values by setting the and class properties respectively
determines if the metering of the bands frequencies is active

()
use this method to roll all of the class properties back to their initial state
returns nothing