MFSetAttributeRatio function (mfapi.h)

Article
02/22/2024

Sets a ratio as a 64-bit attribute value.

Syntax

HRESULT MFSetAttributeRatio(
  [in] IMFAttributes *pAttributes,
  [in] REFGUID       guidKey,
  [in] UINT32        unNumerator,
  [in] UINT32        unDenominator
);

Parameters

[in] pAttributes

A pointer to the IMFAttributes interface of the attribute store.

[in] guidKey

A GUID that identifies the value to set. If this key already exists, the function overwrites the old value.

[in] unNumerator

The numerator of the ratio.

[in] unDenominator

The denominator of the ratio.

Return value

If this function succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.

Remarks

Some attributes specify a ratio as a packed UINT64 value. This function packs the numerator and denominator into a single UINT64 value.

Requirements

Requirement	Value
Minimum supported client	Windows Vista [desktop apps \| UWP apps]
Minimum supported server	Windows Server 2008 [desktop apps \| UWP apps]
Target Platform	Windows
Header	mfapi.h