PDD_VPORTCB_GETFIELD callback function

The DdVideoPortGetField callback function determines whether the current field of an interlaced signal is even or odd.

Syntax


PDD_VPORTCB_GETFIELD DdVideoPortGetField;

DWORD APIENTRY DdVideoPortGetField(
   PDD_GETVPORTFIELDDATA lpGetField
)
{ ... }

Parameters

lpGetField

Points to a DD_GETVPORTFIELDDATA structure that contains the information required for the driver to determine whether the current field is even or odd.

Return value

DdVideoPortGetField returns one of the following callback codes:

DDHAL_DRIVER_HANDLED
DDHAL_DRIVER_NOTHANDLED

Remarks

DirectDraw drivers that set the DDVPCAPS_READBACKFIELD flag in the dwCaps member of the DDVIDEOPORTCAPS structure must implement DdVideoPortGetField.

The driver should determine whether the current field is even or odd and write TRUE or FALSE in the bField member of the DD_GETVPORTFIELDDATA structure at lpGetField, accordingly. If the query cannot be performed because the hardware video port is disabled, the driver should return DDHAL_DRIVER_HANDLED and set DDERR_VIDEONOTACTIVE in the ddRVal member of DD_GETVPORTFIELDDATA.

Requirements

Target platform

Desktop

Header

Ddrawint.h (include Winddi.h)

See also

DD_GETVPORTFIELDDATA
DDVIDEOPORTCAPS

 

 

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