[FFmpeg-devel] [PATCH v3 1/4] libavutil/dovi_meta: Add nlq_pivots to AVDOVIDataMapping

[Andreas Rheinhardt]

quietvoid:
> The NLQ pivots are not documented but should be present
> in the header for profile 7 RPU format.
> It has been verified using Dolby's verification toolkit.
> 
> Signed-off-by: quietvoid <tcChlisop0 at gmail.com>
> ---
>  libavcodec/dovi_rpu.c | 9 ++++++++-
>  libavutil/dovi_meta.h | 1 +
>  2 files changed, 9 insertions(+), 1 deletion(-)
> 
> diff --git a/libavcodec/dovi_rpu.c b/libavcodec/dovi_rpu.c
> index a87562c8a3..31e87cfbcc 100644
> --- a/libavcodec/dovi_rpu.c
> +++ b/libavcodec/dovi_rpu.c
> @@ -117,7 +117,7 @@ int ff_dovi_attach_side_data(DOVIContext *s, AVFrame *frame)
>      /* Copy only the parts of these structs known to us at compiler-time. */
>  #define COPY(t, a, b, last) memcpy(a, b, offsetof(t, last) + sizeof((b)->last))
>      COPY(AVDOVIRpuDataHeader, av_dovi_get_header(dovi), &s->header, disable_residual_flag);
> -    COPY(AVDOVIDataMapping, av_dovi_get_mapping(dovi), s->mapping, nlq[2].linear_deadzone_threshold);
> +    COPY(AVDOVIDataMapping, av_dovi_get_mapping(dovi), s->mapping, nlq_pivots[1]);

Do we need the [1] here? I think not.

>      COPY(AVDOVIColorMetadata, av_dovi_get_color(dovi), s->color, source_diagonal);
>      return 0;
>  }
> @@ -315,7 +315,14 @@ int ff_dovi_rpu_parse(DOVIContext *s, const uint8_t *rpu, size_t rpu_size)
>          }
>  
>          if (use_nlq) {
> +            int nlq_pivot = 0;
>              vdr->mapping.nlq_method_idc = get_bits(gb, 3);
> +
> +            for (int i = 0; i < 2; i++) {
> +                nlq_pivot += get_bits(gb, hdr->bl_bit_depth);
> +                vdr->mapping.nlq_pivots[i] = av_clip_uint16(nlq_pivot);
> +            }
> +
>              /**
>               * The patent mentions another legal value, NLQ_MU_LAW, but it's
>               * not documented anywhere how to parse or apply that type of NLQ.
> diff --git a/libavutil/dovi_meta.h b/libavutil/dovi_meta.h
> index 3d11e02bff..6afc7b055a 100644
> --- a/libavutil/dovi_meta.h
> +++ b/libavutil/dovi_meta.h
> @@ -147,6 +147,7 @@ typedef struct AVDOVIDataMapping {
>      uint32_t num_x_partitions;
>      uint32_t num_y_partitions;
>      AVDOVINLQParams nlq[3]; /* per component */
> +    uint16_t nlq_pivots[2]; /* nlq_pred_pivot_value */
>  } AVDOVIDataMapping;
>  
>  /**