DXVA2_VideoChromaSubSampling enumeration (dxva2api.h)

Article
01/31/2022

Describes how chroma values are positioned relative to the luma samples in a YUV video frame. These flags are used in the DXVA2_ExtendedFormat structure.

Syntax

typedef enum _DXVA2_VideoChromaSubSampling {
  DXVA2_VideoChromaSubsamplingMask = 0xf,
  DXVA2_VideoChromaSubsampling_Unknown = 0,
  DXVA2_VideoChromaSubsampling_ProgressiveChroma = 0x8,
  DXVA2_VideoChromaSubsampling_Horizontally_Cosited = 0x4,
  DXVA2_VideoChromaSubsampling_Vertically_Cosited = 0x2,
  DXVA2_VideoChromaSubsampling_Vertically_AlignedChromaPlanes = 0x1,
  DXVA2_VideoChromaSubsampling_MPEG2,
  DXVA2_VideoChromaSubsampling_MPEG1,
  DXVA2_VideoChromaSubsampling_DV_PAL,
  DXVA2_VideoChromaSubsampling_Cosited
} DXVA2_VideoChromaSubSampling;

Constants


`DXVA2_VideoChromaSubsamplingMask` Value: 0xf Bitmask to validate flag values. This value is not a valid flag.
`DXVA2_VideoChromaSubsampling_Unknown` Value: 0 Unknown encoding scheme.
`DXVA2_VideoChromaSubsampling_ProgressiveChroma` Value: 0x8 Chroma should be reconstructed as if the underlying video was progressive content, rather than skipping fields or applying chroma filtering to minimize artifacts from reconstructing 4:2:0 interlaced chroma.
`DXVA2_VideoChromaSubsampling_Horizontally_Cosited` Value: 0x4 Horizontally cosited. Chroma samples are aligned horizontally with multiples of the luma samples. If this flag is not set, chroma samples are located 1/2 pixel to the right of the corresponding luma samples.
`DXVA2_VideoChromaSubsampling_Vertically_Cosited` Value: 0x2 Vertically cosited. Chroma samples are aligned vertically with multiples of the luma samples. If this flag is not set, chroma samples are located 1/2 pixel down from the corresponding luma samples.
`DXVA2_VideoChromaSubsampling_Vertically_AlignedChromaPlanes` Value: 0x1 The chroma planes are vertically aligned. If this flag is not set, chroma planes are out of phase by 1/2 chroma sample, and the Cb and Cr samples are sited on alternate lines.
`DXVA2_VideoChromaSubsampling_MPEG2` Specifies the chroma encoding scheme for MPEG-2 video. Chroma samples are aligned horizontally with the luma samples, but are not aligned vertically. The U and V planes are aligned vertically.
`DXVA2_VideoChromaSubsampling_MPEG1` Specifies the chroma encoding scheme for MPEG-1 video.
`DXVA2_VideoChromaSubsampling_DV_PAL` Specifies the chroma encoding scheme for PAL DV video.
`DXVA2_VideoChromaSubsampling_Cosited` Horizontally and vertically cosited. Chroma samples are aligned vertically and horizontally with the luma samples. YUV formats such as 4:4:4, 4:2:2, and 4:1:1 are always cosited in both directions and should use this flag.