EVT_IDD_CX_PARSE_MONITOR_DESCRIPTION2 callback function (iddcx.h)

Article
10/24/2023

The OS calls EVT_IDD_CX_PARSE_MONITOR_DESCRIPTION2 to ask the driver to parse a monitor description into a list of modes that the monitor supports. The OS calls this callback version (instead of EVT_IDD_CX_PARSE_MONITOR_DESCRIPTION) to allow the driver to report extra information needed for HDR10 or WCG monitor modes.

Syntax

EVT_IDD_CX_PARSE_MONITOR_DESCRIPTION2 EvtIddCxParseMonitorDescription2;

NTSTATUS EvtIddCxParseMonitorDescription2(
  const IDARG_IN_PARSEMONITORDESCRIPTION2 *pInArgs,
  IDARG_OUT_PARSEMONITORDESCRIPTION *pOutArgs
)
{...}

Parameters

pInArgs

[in] Pointer to an IDARG_IN_PARSEMONITORDESCRIPTION2 structure that contains the input arguments for this callback function.

pOutArgs

[out] Pointer to an IDARG_OUT_PARSEMONITORDESCRIPTION structure that contains the output arguments for this callback function.

Return value

EVT_IDD_CX_PARSE_MONITOR_DESCRIPTION2 returns an NTSTATUS value. If the operation is successful, it returns STATUS_SUCCESS or another status value for which NT_SUCCESS(status) equals TRUE. Otherwise, it returns an appropriate NTSTATUS error code.

Remarks

A version 1.10 or later indirect display driver that supports HDR must expose this function to report modes. Setting the following IDDCX_WIRE_BITS_PER_COMPONENT values is equivalent to creating a mode via the pre-1.10 functions:

BitsPerComponent.Rgb to IDDCX_BITS_PER_COMPONENT_8
BitsPerComponent.YCbCr444, BitsPerComponent.YCbCr422 and BitsPerComponent.YCbCr420 to IDDCX_BITS_PER_COMPONENT_NONE

Version 1.10 and later drivers that don't set the IDDCX_ADAPTER_FLAGS_CAN_PROCESS_FP16 adapter flag can continue to report only the pre-1.10 function.

The IDDCX_MONITOR_MODE2::BitsPerComponent field is designed to allow multiple formats and bit depths to be reported in a single mode. For example, a driver can report 8 and 10 bits per component in RGB by setting both IDDCX_BITS_PER_COMPONENT_8 and IDDCX_BITS_PER_COMPONENT_10 in IDDCX_MONITOR_MODE2::BitsPerComponent::Rgb. A driver should only report different bits per component as unique modes if other mode details also differ.

Drivers returning modes with SDR WCG or HDR parameters will fail if they have not also reported IDDCX_ADAPTER_FLAGS_CAN_PROCESS_FP16 in the IddCxAdapterInitAsync call. SDR WCG and HDR parameters can be:

Any value for IDDCX_WIRE_BITS_PER_COMPONENT::BitsPerComponent.Rgb other than IDDCX_BITS_PER_COMPONENT_8, or
Any IDDCX_WIRE_BITS_PER_COMPONENT::BitsPerComponent value for YCbCr444, YCbCr422, or YCbCr420 other than IDDCX_BITS_PER_COMPONENT_NONE.

For more information about HDR support, see IddCx version 1.10 updates.

Requirements

Requirement	Value
Minimum supported client	Windows 11, version 22H2 September Update (IddCx version 1.10)
Header	iddcx.h