LINEMEDIACONTROL
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4/8/2010
These 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 for any media-control operation to be effective.
The following table shows the LINEMEDIACONTROL constants.
| Value | Description |
|---|---|
LINEMEDIACONTROL_NONE = 0x00000001 |
No change is to be made to the media stream. |
LINEMEDIACONTROL_PAUSE = 0x00000008 |
Temporarily pause the media stream. |
LINEMEDIACONTROL_RATENORMAL = 0x00000080 |
The speed of the media stream is returned to normal. |
LINEMEDIACONTROL_RATEDOWN = 0x00000040 |
The speed of the media stream is decreased by some stream-defined quantity. |
LINEMEDIACONTROL_RATEUP = 0x00000020 |
The speed of the media stream is increased by some stream-defined quantity. |
LINEMEDIACONTROL_RESET = 0x00000004 |
Reset the media stream. Equivalent to an end-of-input. All buffers are released. |
LINEMEDIACONTROL_RESUME = 0x00000010 |
Resume a paused media stream. |
LINEMEDIACONTROL_START = 0x00000002 |
Start the media stream. |
LINEMEDIACONTROL_VOLUMEDOWN = 0x00000200 |
The amplitude of the media stream is decreased by some stream-defined quantity. |
LINEMEDIACONTROL_VOLUMENORMAL = 0x00000400 |
The amplitude of the media stream is returned to normal. |
LINEMEDIACONTROL_VOLUMEUP = 0x00000100 |
The amplitude of the media stream is increased by some stream-defined quantity. |
Remarks
The high-order 16 bits can be assigned for device-specific extensions. The low-order 16 bits are reserved.
Media control is provided to improve performance of actions on media streams 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 to replace the native media functions.
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 type. Consult a line's device capabilities to determine whether media control is available on the line.
Requirements
| Header | tapi.h |
| Windows Embedded CE | Windows CE 3.0 and later |
| Windows Mobile | Windows Mobile Version 5.0 and later |