H263_D
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).