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CODECAPI_AVEncVideoEnableSpatialAdaptiveQuantization property

Enables or disables spatial adaptive quantization (AQ) in an encoder MFT.

Data type

BOOL (VT_BOOL)

Property GUID

CODECAPI_AVEncVideoEnableSpatialAdaptiveQuantization

Property value

If the value is TRUE, AQ is enabled. If the value is FALSE, AQ is disabled. The default value is implementation-dependent.

Remarks

When AQ is enabled, if the implementation of AQ supports multiple AQ strengths, the default AQ strength will be used.

When AQ is enabled, the CODECAPI_AVEncVideoEncodeQP value is not strictly followed, as AQ dynamically adjusts Quantization Parameter (QP) values. When AQ is enabled, the CODECAPI_AVEncVideoMaxQP and CODECAPI_AVEncVideoMinQP values are still used as the upper and lower bounds for QP by the AQ algorithm.

Use ICodecAPI::IsSupported to check if the encoder supports this property. Use ICodecAPI::GetValue to query the value of this property. Use ICodecAPI::SetValue to configure this property.

Note that while the variant type of the CODECAPI_AVEncVideoEnableSpatialAdaptiveQuantization property is VT_BOOL, IMFAttributes does not support Boolean attributes. Therefore, you should use SetUINT32 instead. Any non-zero value is interpreted as TRUE. The attribute value will be automatically converted to a VT_BOOL property value when it is transferred to the encoder MFT.

Examples

The following example demonstrates how to use the CODECAPI_AVEncVideoEnableSpatialAdaptiveQuantization property to configure an encoder MFT to enable or disable the spatial adaptive quantization feature.

#include <codecapi.h> 
#include <mfapi.h> 
#include <wil.com.h>
#include <wil/result_macros.h>

//  Inform an encoder MFT to enable or disable the spatial adaptive quantization feature. 
//  This function assumes that the encoder MFT supports ICodecAPI interface. 
//  It checks whether the new property CODECAPI_AVEncVideoEnableSpatialAdaptiveQuantization is supported. 
//  If not supported, it returns E_NOTIMPL. 

HRESULT ConfigureEncoderForSpatialAdaptiveQuantization(_In_ IMFTransform* encoder) 
{ 
    wil::com_ptr_nothrow<ICodecAPI> codecAPI; 
    RETURN_IF_FAILED(wil::com_query_to_nothrow(encoder, &codecAPI)); 

    // Check if the encoder supports the property for controlling the usage of spatial adaptive quantization 
    if (!codecAPI->IsSupported(&CODECAPI_AVEncVideoEnableSpatialAdaptiveQuantization)) 
    { 
        return E_NOTIMPL; 
    } 

    // Configure the encoder to enable spatial adaptive quantization 
    VARIANT value{}; 
    value.vt = VT_BOOL; 
    value.boolVal = VARIANT_TRUE; // VARIANT_FALSE: disable; VARIANT_TRUE: enable 
    return codecAPI->SetValue(&CODECAPI_AVEncVideoEnableSpatialAdaptiveQuantization, &value); 
}

Requirements

Requirement Value
Minimum supported client Windows 11, build 26100
Minimum supported server Windows Server 2025
Header Codecapi.h

See also

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