bDXVA_Func Variable

The bDXVA_Func variable is an 8-bit value that is associated with DirectX VA operations as follows.

bDXVA_Func Value Operation

1

Compressed picture decoding

2

Alpha-blend data loading

3

Alpha-blend combination

4

Picture resampling

The bDXVA_Func variable is used to perform the following tasks:

  • Probe and lock a configuration for a specific DirectX VA function. This is done by including bDXVA_Func in a DXVA_ConfigQueryOrReplyFlag variable and in a DXVA_ConfigQueryOrReplyFlag variable when these variables are sent in the dwFunction member of a DD_RENDERMOCOMPDATA structure in a call to DdMoCompRender.

  • Specify the function associated with a configuration structure passed with a probe or lock command by inclusion with a DXVA_ConfigQueryOrReplyFlag variable in a DXVA_ConfigQueryOrReplyFlag variable sent in the dwFunction member of the following structures: DXVA_ConfigPictureDecode for compressed picture decoding DXVA_ConfigAlphaLoad for alpha-blending data loading DXVA_ConfigAlphaCombine for alpha-blending combination

  • Initialize an encryption protocol for a specific DirectX VA function by inclusion in a DXVA_EncryptProtocolFunc variable sent in the dwFunction member of a DD_RENDERMOCOMPDATA structure in a call to DdMoCompRender.

  • Specify the function associated with an encryption protocol by inclusion in the dwFunction member of the DXVA_EncryptProtocolHeader structure.

  • Signal an operation to be performed by inclusion in a series of bDXVA_Func byte values in the dwFunction member of a DD_RENDERMOCOMPDATA structure in a call to DdMoCompRender. The first bDXVA_Func operation is specified in the most significant byte, the next operation is specified in the next most significant byte, and so on. Remaining bytes in dwFunction not used to signal an operation are set to zero.