VideoMeta

Extra buffer metadata describing image properties

This meta can also be used by downstream elements to specifiy their buffer layout requirements for upstream. Upstream should try to fit those requirements, if possible, in order to prevent buffer copies.

This is done by passing a custom #GstStructure to gst.query.Query.addAllocationMeta when handling the ALLOCATION query. This structure should be named 'video-meta' and can have the following fields:

padding-top (uint): extra pixels on the top
padding-bottom (uint): extra pixels on the bottom
padding-left (uint): extra pixels on the left side
padding-right (uint): extra pixels on the right side

The padding fields have the same semantic as #GstVideoMeta.alignment and so represent the paddings requested on produced video buffers.

Since 1.24 it can be serialized using gst.meta.Meta.serialize and gst.meta.Meta.deserialize.

class VideoMeta {

GstVideoMeta cInstance;

bool getPlaneHeight(uint[] planeHeight);

bool getPlaneSize(size_t[] planeSize);

bool map(uint plane, gst.map_info.MapInfo info, void* data, int stride, gst.types.MapFlags flags);

bool unmap(uint plane, gst.map_info.MapInfo info);

static gst.meta_info.MetaInfo getInfo();

}

Members

Functions

getPlaneHeight bool getPlaneHeight(uint[] planeHeight): Compute the padded height of each plane from meta (padded size divided by stride).
getPlaneSize bool getPlaneSize(size_t[] planeSize): Compute the size, in bytes, of each video plane described in meta including any padding and alignment constraint defined in meta->alignment.
map bool map(uint plane, gst.map_info.MapInfo info, void* data, int stride, gst.types.MapFlags flags): Map the video plane with index plane in meta and return a pointer to the first byte of the plane and the stride of the plane.
unmap bool unmap(uint plane, gst.map_info.MapInfo info): Unmap a previously mapped plane with gstvideo.video_meta.VideoMeta.map.

Static functions

getInfo gst.meta_info.MetaInfo getInfo()

gstvideo video_meta classes

VideoMeta