DVM_PALETTERGB555

The DVM_PALETTERGB555 message requests a user-mode video capture driver to store a logical palette and an RGB555 translation table.

Parameters

dwDriverID

Video channel identifier. One of VIDEO_EXTERNALIN, VIDEO_IN, VIDEO_OUT, VIDEO_EXTERNALOUT. (For details, see Opening Video Channels.) Typically, drivers only allow VIDEO_IN for this message.

hDriver

Driver handle.

uMsg

DVM_PALETTERGB555

lParam1

Contains flags. The following flags are defined.

Flag	Definition
VIDEO_CONFIGURE_SET	The driver sets a client-specified palette description and translation table.
VIDEO_CONFIGURE_QUERY	The driver indicates whether or not it supports the DVM_PALETTERGB555 message.

lParam2

Pointer to a VIDEOCONFIGPARMS structure. For the DVM_PALETTERGB555 message, the structure members are used as follows:

lpdwReturn

Pointer to a DWORD in which the driver returns the size, in bytes, of the currently stored palette, if the VIDEO_CONFIGURE_QUERYSIZE flag is set.

lpData1

Pointer to a client-supplied LOGPALETTE structure. (For more information about the LOGPALETTE structure, see the Win32 SDK.)

dwSize1

Size, in bytes, of the LOGPALETTE structure.

lpData2

Pointer to a 32-kilobyte RGB555 translation table.

dwSize2

Size of the translation table. Must be 32768.

Return Value

The driver should return DV_ERR_OK if the operation succeeds. Otherwise, it should return one of the DV_ERR error codes defined in msvideo.h. Custom error codes are also allowed (see DVM_GETERRORTEXT).

Comments

A client sends the DVM_PALETTERGB555 message by calling the driver’s DriverProc entry point, passing the specified parameter values. Applications can send this message by calling the videoConfigure function, which is described in the Video for Windows Development Kit.

This message does not support the VIDEO_CONFIGURE_GET flag. Clients can send DVM_PALETTE to obtain the current palette.

For more information on how drivers can handle palettes and color translation tables, see Setting Palettes.

User-mode video capture drivers using VCUser.lib can call VC_ConfigFormat when processing the DVM_PALETTERGB555 message.