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MCI_QUALITY command

The MCI_QUALITY command defines a custom quality level for audio, video, or still image data compression. Digital-video devices recognize this command.

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

MCIERROR mciSendCommand(
  MCIDEVICEID wDeviceID, 
  MCI_QUALITY, 
  DWORD dwFlags, 
  (DWORD) (LPMCI_DGV_QUALITY_PARMS) lpQuality
);

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.

lpQuality

Pointer to an MCI_DGV_QUALITY_PARMS structure.

Return Value

Returns zero if successful or an error otherwise.

Remarks

The name defined for this quality level can be used when setting the audio, video, or still quality with the MCI_SETAUDIO and MCI_SETVIDEO commands.

The following additional flags apply to digital-video devices:

MCI_QUALITY_ALG

The lpstrAlgorithm member of the structure identified by lpQuality contains an address of a buffer containing the name of the algorithm. This algorithm must be supported by the device driver, and must be compatible with the audio, still, or video descriptor that is used. If this flag is omitted, the current algorithm is used.

MCI_QUALITY_DIALOG

The device driver should display a dialog box for specifying the quality level. The dialog box has algorithm-specific fields used internally by the device driver to create a structure describing a specific quality level.

MCI_QUALITY_HANDLE

The dwHandle member of the structure identified by lpQuality contains a handle to a structure. The structure contains algorithmic-specific data describing the specific quality level. The format of the structures for the algorithms is device dependent.

MCI_QUALITY_ITEM

A constant indicating the type of algorithm is included in the dwItem member of the structure identified by lpQuality.

MCI_QUALITY_NAME

The lpstrName member of the structure identified by lpQuality contains an address of a buffer containing the quality descriptor.

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