[FFmpeg-devel] [PATCH 1/3] avcodec/dxva2_hevc: add support for parsing HEVC Range Extension data

[Hendrik Leppkes]

On Fri, Mar 13, 2020 at 11:25 AM Steve Lhomme <robux4 at ycbcr.xyz> wrote:
>
> Mimick the existing structure and add the extra fields from the Range Extension
> in a wrapping structure.
>
> The FF_DXVA2_WORKAROUND_HEVC_REXT is set by the decoder user to signal the
> selected decoder is expecting this extended structure rather than the default
> one.
> ---
>  libavcodec/d3d11va.h    |  1 +
>  libavcodec/dxva2.h      |  1 +
>  libavcodec/dxva2_hevc.c | 79 ++++++++++++++++++++++++++++++++++++++---
>  3 files changed, 76 insertions(+), 5 deletions(-)
>
> diff --git a/libavcodec/d3d11va.h b/libavcodec/d3d11va.h
> index 6816b6c1e6..68a69c372d 100644
> --- a/libavcodec/d3d11va.h
> +++ b/libavcodec/d3d11va.h
> @@ -47,6 +47,7 @@
>
>  #define FF_DXVA2_WORKAROUND_SCALING_LIST_ZIGZAG 1 ///< Work around for Direct3D11 and old UVD/UVD+ ATI video cards
>  #define FF_DXVA2_WORKAROUND_INTEL_CLEARVIDEO    2 ///< Work around for Direct3D11 and old Intel GPUs with ClearVideo interface
> +#define FF_DXVA2_WORKAROUND_HEVC_REXT           4 ///< Signal the D3D11VA decoder is using the HEVC Rext picture structure
>
>  /**
>   * This structure is used to provides the necessary configurations and data
> diff --git a/libavcodec/dxva2.h b/libavcodec/dxva2.h
> index 22c93992f2..024999239d 100644
> --- a/libavcodec/dxva2.h
> +++ b/libavcodec/dxva2.h
> @@ -47,6 +47,7 @@
>
>  #define FF_DXVA2_WORKAROUND_SCALING_LIST_ZIGZAG 1 ///< Work around for DXVA2 and old UVD/UVD+ ATI video cards
>  #define FF_DXVA2_WORKAROUND_INTEL_CLEARVIDEO    2 ///< Work around for DXVA2 and old Intel GPUs with ClearVideo interface
> +#define FF_DXVA2_WORKAROUND_HEVC_REXT           4 ///< Signal the DXVA2 decoder is using the HEVC Rext picture structure
>
>  /**
>   * This structure is used to provides the necessary configurations and data
> diff --git a/libavcodec/dxva2_hevc.c b/libavcodec/dxva2_hevc.c
> index dbb701fb1c..98b3e74bd7 100644
> --- a/libavcodec/dxva2_hevc.c
> +++ b/libavcodec/dxva2_hevc.c
> @@ -26,10 +26,47 @@
>  #include "hevc_data.h"
>  #include "hevcdec.h"
>
> +#pragma pack(push, 1)
> +typedef struct
> +{
> +    DXVA_PicParams_HEVC main;
> +
> +    // HEVC Range Extension
> +    __C89_NAMELESS union {
> +        __C89_NAMELESS struct {
> +            UINT32 transform_skip_rotation_enabled_flag : 1;
> +            UINT32 transform_skip_context_enabled_flag : 1;
> +            UINT32 implicit_rdpcm_enabled_flag : 1;
> +            UINT32 explicit_rdpcm_enabled_flag : 1;
> +            UINT32 extended_precision_processing_flag : 1;
> +            UINT32 intra_smoothing_disabled_flag : 1;
> +            UINT32 high_precision_offsets_enabled_flag : 1;
> +            UINT32 persistent_rice_adaptation_enabled_flag : 1;
> +            UINT32 cabac_bypass_alignment_enabled_flag : 1;
> +            UINT32 cross_component_prediction_enabled_flag : 1;
> +            UINT32 chroma_qp_offset_list_enabled_flag : 1;
> +            UINT32 BitDepthLuma16 : 1; // TODO merge in ReservedBits5 if not needed
> +            UINT32 BitDepthChroma16 : 1; // TODO merge in ReservedBits5 if not needed
> +            UINT32 ReservedBits8 : 19;
> +        };
> +        UINT32 dwRangeExtensionFlags;
> +    };
> +
> +    UCHAR diff_cu_chroma_qp_offset_depth;
> +    UCHAR chroma_qp_offset_list_len_minus1;
> +    UCHAR log2_sao_offset_scale_luma;
> +    UCHAR log2_sao_offset_scale_chroma;
> +    UCHAR log2_max_transform_skip_block_size_minus2;
> +    CHAR cb_qp_offset_list[6];
> +    CHAR cr_qp_offset_list[6];
> +
> +} DXVA_PicParams_HEVC_Rext;
> +#pragma pack(pop)
> +

Where is this struct specified? I don't see it in the latest released
Windows SDK.

- Hendrik