[FFmpeg-devel] [PATCH v3 1/5] avutil: add ambient viewing environment metadata side data

[Andreas Rheinhardt]

lance.lmwang at gmail.com:
> From: Limin Wang <lance.lmwang at gmail.com>
> 
> Signed-off-by: Limin Wang <lance.lmwang at gmail.com>
> ---
>  libavutil/frame.c                      |  1 +
>  libavutil/frame.h                      |  6 +++++
>  libavutil/mastering_display_metadata.c | 23 +++++++++++++++++
>  libavutil/mastering_display_metadata.h | 45 ++++++++++++++++++++++++++++++++++
>  libavutil/version.h                    |  2 +-
>  5 files changed, 76 insertions(+), 1 deletion(-)
> 
> diff --git a/libavutil/frame.c b/libavutil/frame.c
> index fbb869f..8882da2 100644
> --- a/libavutil/frame.c
> +++ b/libavutil/frame.c
> @@ -815,6 +815,7 @@ const char *av_frame_side_data_name(enum AVFrameSideDataType type)
>      case AV_FRAME_DATA_DETECTION_BBOXES:            return "Bounding boxes for object detection and classification";
>      case AV_FRAME_DATA_DOVI_RPU_BUFFER:             return "Dolby Vision RPU Data";
>      case AV_FRAME_DATA_DOVI_METADATA:               return "Dolby Vision Metadata";
> +    case AV_FRAME_DATA_AMBIENT_VIEWING_ENV:         return "Ambient Viewing Environment";
>      }
>      return NULL;
>  }
> diff --git a/libavutil/frame.h b/libavutil/frame.h
> index 33fac20..92413c9 100644
> --- a/libavutil/frame.h
> +++ b/libavutil/frame.h
> @@ -209,6 +209,12 @@ enum AVFrameSideDataType {
>       * volume transform - CUVA 005.1-2021.
>       */
>      AV_FRAME_DATA_DYNAMIC_HDR_VIVID,
> +
> +    /**
> +     * ambient viewing environment for a video frame, as described by
> +     * the AVAmbientViewingEnv
> +     */
> +    AV_FRAME_DATA_AMBIENT_VIEWING_ENV,
>  };
>  
>  enum AVActiveFormatDescription {
> diff --git a/libavutil/mastering_display_metadata.c b/libavutil/mastering_display_metadata.c
> index 6069347..f094eab 100644
> --- a/libavutil/mastering_display_metadata.c
> +++ b/libavutil/mastering_display_metadata.c
> @@ -64,3 +64,26 @@ AVContentLightMetadata *av_content_light_metadata_create_side_data(AVFrame *fram
>  
>      return (AVContentLightMetadata *)side_data->data;
>  }
> +
> +AVAmbientViewingEnv *av_ambient_viewing_env_alloc(size_t *size)
> +{
> +    AVAmbientViewingEnv *metadata = av_mallocz(sizeof(*metadata));
> +
> +    if (size)
> +        *size = sizeof(*metadata);
> +
> +    return metadata;
> +}
> +
> +AVAmbientViewingEnv *av_ambient_viewing_env_create_side_data(AVFrame *frame)
> +{
> +    AVFrameSideData *side_data = av_frame_new_side_data(frame,
> +            AV_FRAME_DATA_AMBIENT_VIEWING_ENV,
> +            sizeof(AVAmbientViewingEnv));
> +    if (!side_data)
> +        return NULL;
> +
> +    memset(side_data->data, 0, sizeof(AVAmbientViewingEnv));
> +
> +    return (AVAmbientViewingEnv *)side_data->data;
> +}
> diff --git a/libavutil/mastering_display_metadata.h b/libavutil/mastering_display_metadata.h
> index c23b07c..c1ba659 100644
> --- a/libavutil/mastering_display_metadata.h
> +++ b/libavutil/mastering_display_metadata.h
> @@ -125,4 +125,49 @@ AVContentLightMetadata *av_content_light_metadata_alloc(size_t *size);
>   */
>  AVContentLightMetadata *av_content_light_metadata_create_side_data(AVFrame *frame);
>  
> +/**
> + * The characteristics of the nominal ambient viewing environment for
> + * the display of the associated video content.
> + * To be used as payload of a AVFrameSideData the appropriate type.
> + *
> + * @note The struct should be allocated with av_ambient_viewing_env_alloc()
> + *       and its size is not a part of the public ABI.
> + */
> +typedef struct AVAmbientViewingEnv {
> +    /**
> +     * specifies the environmental illuminance of the ambient viewing
> +     * environment in units of 0.0001 lux.
> +     * ambient_illuminance shall not be equal to 0.
> +     */
> +    uint32_t ambient_illuminance;
> +    /**
> +     * specify the normalized x and y chromaticity coordinates, respectively,
> +     * of the environmental ambient light in the nominal viewing environment,
> +     * according to the CIE 1931 definition of x and y as specified in ISO
> +     * 11664-1 (see also ISO 11664-3 and CIE 15), in normalized increments of
> +     * 0.00002. The values of ambient_light_x and ambient_light_y shall be in
> +     * the range of 0 to 50000
> +     */
> +    uint16_t ambient_light_x;
> +    uint16_t ambient_light_y;
> +} AVAmbientViewingEnv;
> +
> +/**
> + * Allocate an AVAmbientViewingEnv structure and set its fields to
> + * default values. The resulting struct can be freed using av_freep().
> + *
> + * @return An AVAmbientViewingEnv filled with default values or NULL
> + *         on failure.
> + */
> +AVAmbientViewingEnv *av_ambient_viewing_env_alloc(size_t *size);
> +
> +/**
> + * Allocate a complete AVAmbientViewingEnv and add it to the frame.
> + *
> + * @param frame The frame which side data is added to.
> + *
> + * @return The AVAmbientViewingEnv structure to be filled by caller.
> + */
> +AVAmbientViewingEnv *av_ambient_viewing_env_create_side_data(AVFrame *frame);

All this boilerplate code for the various side-data--types makes me
wonder whether they should not be replaced by something like
void *av_frame_side_data_alloc(enum AVFrameSideDataType, size_t *size)
and a corresponding av_frame_create_side_data(AVFrame *frame, enum
AVFrameSideDataType).
These functions would return an error in case it doesn't make sense to
create a side data this way (because there is no struct associated to
this side data type or because the size of this struct depends upon
other parameters, too).

> +
>  #endif /* AVUTIL_MASTERING_DISPLAY_METADATA_H */
> diff --git a/libavutil/version.h b/libavutil/version.h
> index 6735c20..998202f 100644
> --- a/libavutil/version.h
> +++ b/libavutil/version.h
> @@ -79,7 +79,7 @@
>   */
>  
>  #define LIBAVUTIL_VERSION_MAJOR  57
> -#define LIBAVUTIL_VERSION_MINOR  24
> +#define LIBAVUTIL_VERSION_MINOR  25
>  #define LIBAVUTIL_VERSION_MICRO 101

Micro needs to be reset when minor is bumped.

>  
>  #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \