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H263_D

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The H263_D restricted profile contains the set of features required for support of ITU-T Rec. H.263 and a specific set of enhanced optional capabilities. Support of this profile is currently encouraged, but not required. This set of features is specified by the restrictions for the H263_C restricted profile, except for the following additional restrictions.

Restrictions on DXVA_ConnectMode

The following restriction on the DXVA_ConnectMode structure applies when the bDXVA_Func variable defined in the dwFunction member of the DXVA_ConfigPictureDecode structure is equal to 1 (picture decoding) or 4 (picture resampling).

Structure Member Value

wRestrictedMode

DXVA_RESTRICTED_MODE_H263_D

Restrictions on DXVA_PictureParameters

Structure Member Value

bBidirectionalAveragingMode

1 (H.263 bidirectional averaging) or 0 (MPEG-2 bidirectional averaging)

bMV_RPS

Zero or 1

Restrictions on DXVA_MBctrl_I_HostResidDiff_1, DXVA_MBctrl_I_OffHostIDCT_1, DXVA_MBctrl_P_HostResidDiff_1, and DXVA_MBctrl_P_OffHostIDCT_1

Structure Member Value

wMBtype

The MotionBackward variable defined by this member may be zero or 1.

Restrictions on Bitstream Buffers

The contents of any bitstream buffers may also contain data in the H.263 video format with any subset of Annexes K, O, P (factor-of-two resizing with clipping only in one or both dimensions), S, and U.

Restrictions on DXVA_PicResample

The following restrictions on the DXVA_PicResample structure apply when the bDXVA_Func variable defined in the dwFunction member of the DXVA_ConfigPictureDecode structure is equal to 4.

Structure Member Value

dwPicResampleSourceWidth

Must be equal to dwPicResampleDestWidth or related to dwPicResampleDestWidth by a multiplication factor of 2 (or 1/2).

dwPicResampleDestWidth

Must be equal to dwPicResampleSourceWidth or related to dwPicResampleSourceWidth by a multiplication factor of 2 (or 1/2).

dwPicResampleSourceHeight

Must be equal to dwPicResampleDestHeight or related to dwPicResampleDestHeight by a multiplication factor of 2 (or 1/2).

dwPicResampleDestHeight

Must be equal to dwPicResampleSourceHeight or related to dwPicResampleSourceHeight by a multiplication factor of 2 (or 1/2).

If dwPicResampleSourceHeight and dwPicResampleDestHeight are equal, dwPicResampleSourceWidth and dwPicResampleDestWidth must be related by a multiplication factor of 2 (or 1/2). If dwPicResampleSourceHeight and dwPicResampleDestHeight indicate an upsampling operation, dwPicResampleSourceWidth and dwPicResampleDestWidth must not indicate a downsampling operation, and vice versa.

Note   Although H.263 requires only support of the bBidirectionalAveragingMode member of DXVA_PictureParameters equal to 1 when MotionForward is 1 and MotionBackward is 1, the H263_D restricted profile also allows bBidirectionalAveragingMode to be zero. This is intended to allow the H263_D restricted profile to support MPEG-4 video as well as H.263 video (MPEG-4 uses the MPEG-1/MPEG-2 style of bidirectional averaging).