LINEMEDIACONTROL_ Constants

The LINEMEDIACONTROL_ bit-flag constants describe a set of generic operations on media streams. The interpretations are determined by the media stream. The line device must have the media control capability in order for any media control operations to be effective.

LINEMEDIACONTROL_NONE: No change is to be made to the media stream.
LINEMEDIACONTROL_START: Start the media stream.
LINEMEDIACONTROL_RESET: Reset the media stream. Provide the effect of an end-of-input. All buffers are released.
LINEMEDIACONTROL_PAUSE: Temporarily pause the media stream.
LINEMEDIACONTROL_RESUME: Resume a paused media stream.
LINEMEDIACONTROL_RATEUP: The speed of the media stream is increased by some stream-defined quantity.
LINEMEDIACONTROL_RATEDOWN: The speed of the media stream is decreased by some stream-defined quantity.
LINEMEDIACONTROL_RATENORMAL: The speed of the media stream is returned to normal.
LINEMEDIACONTROL_VOLUMEUP: The amplitude of the media stream is increased by some stream-defined quantity.
LINEMEDIACONTROL_VOLUMEDOWN: The amplitude of the media stream is decreased by some stream-defined quantity.
LINEMEDIACONTROL_VOLUMENORMAL: The amplitude of the media stream is returned to normal.

The high-order 16 bits can be assigned for device-specific extensions. The low-order 16 bits are reserved.

Media control is provided as a way of improving the performance of actions on media streams on calls in response to telephony related events. The application should normally manage a media stream through the media-specific API; the media control functionality provided here is not intended as a replacemenet for the native media APIs.

Media control actions can be associated with the detection of digits, the detection of tones, the transition into a call state, and the detection of a media mode. Consult a line's device capabilities to determine whether media control is available on a line.

LINEMEDIACONTROL_ Constants

See Also