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WICHeifHdrProperties enumeration (wincodec.h)

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Specifies the HDR properties of a High Efficiency Image Format (HEIF) image.

Syntax

typedef enum WICHeifHdrProperties {
  WICHeifHdrMaximumLuminanceLevel = 0x1,
  WICHeifHdrMaximumFrameAverageLuminanceLevel = 0x2,
  WICHeifHdrMinimumMasteringDisplayLuminanceLevel = 0x3,
  WICHeifHdrMaximumMasteringDisplayLuminanceLevel = 0x4,
  WICHeifHdrCustomVideoPrimaries = 0x5,
  WICHeifHdrProperties_FORCE_DWORD = 0x7fffffff
} ;

Constants

 
WICHeifHdrMaximumLuminanceLevel
Value: 0x1
[VT_UI2] Specifies the maximum luminance level of the content in Nits.
WICHeifHdrMaximumFrameAverageLuminanceLevel
Value: 0x2
[VT_UI2] Specifies the maximum average per-frame luminance level of the content in Nits.
WICHeifHdrMinimumMasteringDisplayLuminanceLevel
Value: 0x3
[VT_UI2] Specifies the maximum luminance of the display on which the content was authored, in Nits.
WICHeifHdrMaximumMasteringDisplayLuminanceLevel
Value: 0x4
[VT_UI2] Specifies the maximum luminance of the display on which the content was authored, in Nits.
WICHeifHdrCustomVideoPrimaries
Value: 0x5
[VT_BLOB] Specifies custom color primaries for a video media type. The value of this property is a MT_CUSTOM_VIDEO_PRIMARIESstructure, returned as an array of bytes (VT_BLOB).
WICHeifHdrProperties_FORCE_DWORD
Value: 0x7fffffff

Remarks

Use IWicMetadataReader::GetValue to retrieve the value of the properties specified with this enumeration. Instantiate the IWicMetadataReader instance using the GUID CLSID_WICMetadataReader. Call IWicMetadataReader::GetMetadataFormat and confirm that the value is GUID_MetadataFormatHeifHDR to verify that the metadata format is HEIF HDR metadata.

Not all HEIF HDR images will have all of these properties present in the file, so only those properties that are available will be exposed by the metadata reader.

using namespace winrt;

std::optional<uint32_t> GetMaximumLuminanceLevelFromMetadataReader(_In_ IWICMetadataReader* metadataReader)
{
    std::optional<uint32_t> result;
    GUID metadataFormat;

    // Retrieve the format of the metadata used by this IWICMetadataReader
    check_hresult(metadataReader->GetMetadataFormat(&metadataFormat));

    // This function only handles HEIF HDR metadata
    if (metadataFormat != GUID_MetadataFormatHeifHDR)
    {
        throw_hresult(E_INVALIDARG);
    }

    PROPVARIANT variantId = {};
    PROPVARIANT variantValue = {};

    variantId.vt = VT_UI4;
    variantId.uiVal = WICHeifHdrMaximumLuminanceLevel;
    if (SUCCEEDED(metadataReader->GetValue(nullptr, &variantId, &variantValue)))
    {
        if (variantValue.vt == VT_UI4)
        {
            result = variantValue.uiVal;
        }
        PropVariantClear(&variantValue);
    }

    return result;
}

Requirements

Requirement Value
Minimum supported client Windows 10, version 1903 [desktop apps only]
Minimum supported server Windows Server, version 1903 [desktop apps only]
Header wincodec.h