Struct VideoMeta

pub struct VideoMeta(/* private fields */);

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 gst::Structure to [gst::Query::add_allocation_meta()][crate::gst::Query::add_allocation_meta()] 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
• stride-align0 (uint): stride align requirements for plane 0
• stride-align1 (uint): stride align requirements for plane 1
• stride-align2 (uint): stride align requirements for plane 2
• stride-align3 (uint): stride align requirements for plane 3 The padding and stride-align fields have the same semantic as GstVideoMeta.alignment and so represent the paddings and stride-align requested on produced video buffers.

Since 1.24 it can be serialized using gst_meta_serialize() and gst_meta_deserialize().

Implementations

impl VideoMeta

pub fn add( buffer: &mut BufferRef, video_frame_flags: VideoFrameFlags, format: VideoFormat, width: u32, height: u32, ) -> Result<MetaRefMut<'_, Self, Standalone>, BoolError>

pub fn add_full<'a>( buffer: &'a mut BufferRef, video_frame_flags: VideoFrameFlags, format: VideoFormat, width: u32, height: u32, offset: &[usize], stride: &[i32], ) -> Result<MetaRefMut<'a, Self, Standalone>, BoolError>

pub fn video_frame_flags(&self) -> VideoFrameFlags

pub fn format(&self) -> VideoFormat

pub fn id(&self) -> i32

pub fn width(&self) -> u32

pub fn height(&self) -> u32

pub fn n_planes(&self) -> u32

pub fn offset(&self) -> &[usize]

pub fn stride(&self) -> &[i32]

pub fn alignment(&self) -> VideoAlignment

pub fn plane_size(&self) -> Result<[usize; 4], BoolError>

Compute the size, in bytes, of each video plane described in self including any padding and alignment constraint defined in self->alignment.

Returns

true if self’s alignment is valid and plane_size has been updated, false otherwise

plane_size

array used to store the plane sizes

pub fn plane_height(&self) -> Result<[u32; 4], BoolError>

Compute the padded height of each plane from self (padded size divided by stride).

It is not valid to call this function with a meta associated to a TILED video format.

Returns

true if self’s alignment is valid and plane_height has been updated, false otherwise

plane_height

array used to store the plane height

pub fn set_alignment( &mut self, alignment: &VideoAlignment, ) -> Result<(), BoolError>

Set the alignment of self to alignment. This function checks that the paddings defined in alignment are compatible with the strides defined in self and will fail to update if they are not.

alignment

a GstVideoAlignment

Returns

true if alignment’s meta has been updated, false if not

Trait Implementations

impl Debug for VideoMeta

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl MetaAPI for VideoMeta

type GstType = GstVideoMeta

fn meta_api() -> Type

impl Send for VideoMeta

impl Sync for VideoMeta