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MCI_LIST command

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The MCI_LIST command obtains information about the number and types of inputs available to the device. Digital-video and VCR devices recognize this command.

To send this command, call the mciSendCommand function with the following parameters.

MCIERROR mciSendCommand(
  MCIDEVICEID wDeviceID, 
  MCI_LIST, 
  DWORD dwFlags, 
  (DWORD) (LPMCI_GENERIC_PARMS) lpList
);

Parameters

wDeviceID

Device identifier of the MCI device that is to receive the command message.

dwFlags

MCI_NOTIFY, MCI_WAIT, or MCI_TEST. For information about these flags, see The Wait, Notify, and Test Flags.

lpList

Pointer to an MCI_GENERIC_PARMS structure. (Devices with extended command sets might replace this structure with a device-specific structure.)

Return Value

Returns zero if successful or an error otherwise.

Remarks

The following additional flags apply to the digitalvideo device type:

MCI_DGV_LIST_ALG

The lpstrAlgorithm member of the structure identified by lpList contains an address of a buffer containing the name of an algorithm. The name is used to retrieve the types of quality descriptors associated with an algorithm.

MCI_DGV_LIST_COUNT

Returns the number of options of the specified type.

MCI_DGV_LIST_ITEM

A constant indicating the list type is included in the dwItem member of the structure identified by lpList. This flag is required. Use one of the following constants to indicate the list type:

MCI_DGV_LIST_AUDIO_ALG

The command should retrieve names of audio algorithms.

MCI_DGV_LIST_AUDIO_QUALITY

The command should retrieve audio quality levels. The levels returned are associated with the algorithm referenced by the lpstrAlgorithm member of the structure identified by lpList. If that member is specified using the string "current", then the qualities associated with the current algorithm are returned.

MCI_DGV_LIST_AUDIO_STREAM

The command should retrieve names of audio streams.

MCI_DGV_LIST_STILL_AL

The command should retrieve names of still algorithms.

MCI_DGV_LIST_STILL_QUALITY

The command should retrieve quality levels. The levels returned are associated with the algorithm referenced by the lpstrAlgorithm member of the structure identified by lpList. If that member is specified using the string "current", then the qualities associated with the current algorithm are returned.

MCI_DGV_LIST_VIDEO_ALG

The command should retrieve names of video algorithms.

MCI_DGV_LIST_VIDEO_QUALITY

The command should retrieve video quality levels. The levels returned are associated with the algorithm referenced by the lpstrAlgorithm member of the structure identified by lpList. If that member is specified using the string "current", then the qualities associated with the current algorithm are returned.

MCI_DGV_LIST_VIDEO_SOURCE

The command should return information about the video sources. When used with MCI_DGV_LIST_COUNT, the command returns the number of video sources. When used with MCI_DGV_LIST_NUMBER, the command returns the type of a video source. MCI defines the following types:

  • MCI_DGV_SETVIDEO_SRC_GENERIC
  • MCI_DGV_SETVIDEO_SRC_NTSC
  • MCI_DGV_SETVIDEO_SRC_PAL
  • MCI_DGV_SETVIDEO_SRC_RGB
  • MCI_DGV_SETVIDEO_SRC_SECAM
  • MCI_DGV_SETVIDEO_SRC_SVIDEO

There might be more than one source of each type returned. The generic source type is used when more than one type of signal is allowed for that connector.

MCI_DGV_LIST_VIDEO_STREAM

The command should retrieve names of video streams.

MCI_DGV_LIST_NUMBER

An index is specified in the dwNumber member of the structure identified by lpList. The index must be an integer between 1 and the value returned for the MCI_DGV_LIST_COUNT flag.

For digital-video devices, lpList points to an MCI_DGV_LIST_PARMS structure.

The following additional flags apply to the vcr device type:

MCI_VCR_LIST_AUDIO_SOURCE

List audio inputs or types.

MCI_VCR_LIST_COUNT

Sets the dwReturn member of the structure identified by lpList to the total number of video or audio inputs.

MCI_VCR_LIST_NUMBER

Sets the dwReturn member of the structure identified by lpList to the type of the video or audio input specified by the dwNumber member.

MCI_VCR_LIST_VIDEO_SOURCE

List video inputs or types.

For VCR devices, lpList points to an MCI_VCR_LIST_PARMS structure.

Requirements

Requirement Value
Minimum supported client
 Windows 2000 Professional [desktop apps only]
Minimum supported server
 Windows 2000 Server [desktop apps only]
Header
Mmsystem.h (include Windows.h)

See also

MCI

MCI Commands