Macromedia flash media server 2-client-side actionscript language reference for flash media server 2 ユーザーズマニュアル

Camera class

37

  An integer that specifies the required level of picture quality, as determined by the 

amount of compression being applied to each video frame. Acceptable values range from 1 
(lowest quality, maximum compression) to 100 (highest quality, no compression). To specify 
that picture quality can vary as needed to avoid exceeding bandwidth, pass 0 for 

. The 

default value is 0.

Returns

Nothing. 

Description

Method; sets the maximum amount of bandwidth per second or the required picture quality 
of the current outgoing video feed.

Use this method to specify which element of the outgoing video feed is more important to 
your application—bandwidth use or picture quality.

■

To indicate that bandwidth use takes precedence, pass a value for 

 and 0 for 

. Flash will transmit video at the highest quality possible within the specified 

bandwidth. If necessary, Flash will reduce picture quality to avoid exceeding the specified 
bandwidth. In general, as motion increases, quality decreases.

■

To indicate that quality takes precedence, pass 0 for 

 and a numeric value for 

. Flash will use as much bandwidth as required to maintain the specified quality. 

If necessary, Flash will reduce the frame rate to maintain picture quality. In general, as 
motion increases, bandwidth use also increases.

■

To specify that both bandwidth and quality are equally important, pass numeric values for 
both parameters. Flash will transmit video that achieves the specified quality and that 
doesn’t exceed the specified bandwidth. If necessary, Flash will reduce the frame rate to 
maintain picture quality without exceeding the specified bandwidth.

Example

The following examples illustrate how to use this method to control bandwidth use and 
picture quality:

// Ensure that no more than 8192 (8K/second) is used to send video.
active_cam.setQuality(8192,0);

/* Ensure that no more than 8192 (8K/second) is used to send video
with a minimum quality of 50.*/
active_cam.setQuality(8192,50);

// Ensure a minimum quality of 50, no matter how much bandwidth it takes.
active_cam.setQuality(0,50);

TIP

Streams compressed with the lossless codec are larger than streams compressed with 
the default Sorenson codec.