MCI_UNFREEZE

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The MCI_UNFREEZE command restores motion to an area of the video buffer frozen with the MCI_FREEZE command. Digital-video, VCR, and video-overlay devices recognize this command.

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

MCIERROR mciSendCommand(
  MCIDEVICEID wDeviceID, 
  MCI_UNFREEZE, 
  DWORD dwFlags, 
  (DWORD) (LPMCI_GENERIC_PARMS) lpUnfreeze
);

Parameters

wDeviceID

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

dwFlags

MCI_NOTIFY, MCI_WAIT, or, for digital-video and VCR devices, MCI_TEST. For information about these flags, see The Wait, Notify, and Test Flags.

lpUnfreeze

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

Return Values

Returns zero if successful or an error otherwise.

Remarks

The following additional flag is used with the digitalvideo device type:

MCI_DGV_RECT

The rc member of the structure identified by lpUnfreeze contains a valid display rectangle. The rectangle specifies a region within the frame buffer whose pixels should have their lock mask bit turned off. Rectangular regions are specified as described for the MCI_PUT command. If omitted, the rectangle defaults to the entire frame buffer. By using a sequence of freeze and unfreeze commands with different rectangles, arbitrary patterns of lock mask bits can be described.

For digital-video devices, the lpUnfreeze parameter points to an MCI_DGV_UNFREEZE_PARMS structure. For more information, see the comments for the MCI_DGV_RECT_PARMS structure.

The following additional flags are used with the vcr device type:

MCI_VCR_UNFREEZE_INPUT

Unfreeze the input.

MCI_VCR_UNFREEZE_OUTPUT

Unfreeze the output.

The following additional flag is used with the overlay device type:

MCI_OVLY_RECT

The rc member of the structure identified by lpUnfreeze contains a valid display rectangle. This is a required parameter.

For video-overlay devices, the lpUnfreeze parameter points to an MCI_OVLY_RECT_PARMS structure.

Requirements

**  Windows NT/2000/XP:** Included in Windows NT 3.1 and later.
**  Windows 95/98/Me:** Included in Windows 95 and later.
**  Header:** Declared in Mmsystem.h; include Windows.h.

See Also

MCI, MCI Commands, MCI_DGV_RECT_PARMS, MCI_FREEZE, MCI_GENERIC_PARMS, MCI_OVLY_RECT_PARMS, MCI_PUT