gstvideometa

gstvideometa

Functions

Types and Values

Object Hierarchy


Includes

#include <gst/video/gstvideometa.h>

Description

Functions

gst_video_meta_map ()

gboolean
gst_video_meta_map (GstVideoMeta *meta,
                    guint plane,
                    GstMapInfo *info,
                    gpointer *data,
                    gint *stride,
                    GstMapFlags 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.

Parameters

meta

a GstVideoMeta

 

plane

a plane

 

info

a GstMapInfo

 

data

the data of plane

 

stride

the stride of plane

 

flags

GstMapFlags

 

Returns

TRUE if the map operation was successful.


gst_video_meta_unmap ()

gboolean
gst_video_meta_unmap (GstVideoMeta *meta,
                      guint plane,
                      GstMapInfo *info);

Unmap a previously mapped plane with gst_video_meta_map().

Parameters

meta

a GstVideoMeta

 

plane

a plane

 

info

a GstMapInfo

 

Returns

TRUE if the memory was successfully unmapped.


gst_video_meta_get_info ()

const GstMetaInfo *
gst_video_meta_get_info (void);

gst_buffer_add_video_meta ()

GstVideoMeta *
gst_buffer_add_video_meta (GstBuffer *buffer,
                           GstVideoFrameFlags flags,
                           GstVideoFormat format,
                           guint width,
                           guint height);

Attaches GstVideoMeta metadata to buffer with the given parameters and the default offsets and strides for format and width x height .

This function calculates the default offsets and strides and then calls gst_buffer_add_video_meta_full() with them.

Parameters

buffer

a GstBuffer

 

flags

GstVideoFrameFlags

 

format

a GstVideoFormat

 

width

the width

 

height

the height

 

Returns

the GstVideoMeta on buffer .


gst_buffer_add_video_meta_full ()

GstVideoMeta *
gst_buffer_add_video_meta_full (GstBuffer *buffer,
                                GstVideoFrameFlags flags,
                                GstVideoFormat format,
                                guint width,
                                guint height,
                                guint n_planes,
                                gsize offset[GST_VIDEO_MAX_PLANES],
                                gint stride[GST_VIDEO_MAX_PLANES]);

Attaches GstVideoMeta metadata to buffer with the given parameters.

Parameters

buffer

a GstBuffer

 

flags

GstVideoFrameFlags

 

format

a GstVideoFormat

 

width

the width

 

height

the height

 

n_planes

number of planes

 

offset

offset of each plane

 

stride

stride of each plane

 

Returns

the GstVideoMeta on buffer .


gst_buffer_get_video_meta()

#define gst_buffer_get_video_meta(b) ((GstVideoMeta*)gst_buffer_get_meta((b),GST_VIDEO_META_API_TYPE))

gst_buffer_get_video_meta_id ()

GstVideoMeta *
gst_buffer_get_video_meta_id (GstBuffer *buffer,
                              gint id);

Find the GstVideoMeta on buffer with the given id .

Buffers can contain multiple GstVideoMeta metadata items when dealing with multiview buffers.

Parameters

buffer

a GstBuffer

 

id

a metadata id

 

Returns

the GstVideoMeta with id or NULL when there is no such metadata on buffer .


gst_buffer_add_video_crop_meta()

#define gst_buffer_add_video_crop_meta(b) ((GstVideoCropMeta*)gst_buffer_add_meta((b),GST_VIDEO_CROP_META_INFO, NULL))

gst_buffer_get_video_crop_meta()

#define gst_buffer_get_video_crop_meta(b) ((GstVideoCropMeta*)gst_buffer_get_meta((b),GST_VIDEO_CROP_META_API_TYPE))

gst_buffer_add_video_region_of_interest_meta ()

GstVideoRegionOfInterestMeta *
gst_buffer_add_video_region_of_interest_meta
                               (GstBuffer *buffer,
                                const gchar *roi_type,
                                guint x,
                                guint y,
                                guint w,
                                guint h);

Attaches GstVideoRegionOfInterestMeta metadata to buffer with the given parameters.

Parameters

buffer

a GstBuffer

 

roi_type

Type of the region of interest (e.g. "face")

 

x

X position

 

y

Y position

 

w

width

 

h

height

 

Returns

the GstVideoRegionOfInterestMeta on buffer .


gst_buffer_add_video_region_of_interest_meta_id ()

GstVideoRegionOfInterestMeta *
gst_buffer_add_video_region_of_interest_meta_id
                               (GstBuffer *buffer,
                                GQuark roi_type,
                                guint x,
                                guint y,
                                guint w,
                                guint h);

Attaches GstVideoRegionOfInterestMeta metadata to buffer with the given parameters.

Parameters

buffer

a GstBuffer

 

roi_type

Type of the region of interest (e.g. "face")

 

x

X position

 

y

Y position

 

w

width

 

h

height

 

Returns

the GstVideoRegionOfInterestMeta on buffer .


gst_buffer_get_video_region_of_interest_meta()

#define             gst_buffer_get_video_region_of_interest_meta(b)

gst_buffer_get_video_region_of_interest_meta_id ()

GstVideoRegionOfInterestMeta *
gst_buffer_get_video_region_of_interest_meta_id
                               (GstBuffer *buffer,
                                gint id);

Find the GstVideoRegionOfInterestMeta on buffer with the given id .

Buffers can contain multiple GstVideoRegionOfInterestMeta metadata items if multiple regions of interests are marked on a frame.

Parameters

buffer

a GstBuffer

 

id

a metadata id

 

Returns

the GstVideoeRegionOfInterestMeta with id or NULL when there is no such metadata on buffer .


GstVideoGLTextureUpload ()

gboolean
(*GstVideoGLTextureUpload) (GstVideoGLTextureUploadMeta *meta,
                            guint texture_id[4]);

gst_buffer_add_video_gl_texture_upload_meta ()

GstVideoGLTextureUploadMeta *
gst_buffer_add_video_gl_texture_upload_meta
                               (GstBuffer *buffer,
                                GstVideoGLTextureOrientation texture_orientation,
                                guint n_textures,
                                GstVideoGLTextureType texture_type[4],
                                GstVideoGLTextureUpload upload,
                                gpointer user_data,
                                GBoxedCopyFunc user_data_copy,
                                GBoxedFreeFunc user_data_free);

Attaches GstVideoGLTextureUploadMeta metadata to buffer with the given parameters.

Parameters

buffer

a GstBuffer

 

upload

the function to upload the buffer to a specific texture ID

 

user_data

user data for the implementor of upload

 

user_data_copy

function to copy user_data

 

user_data_free

function to free user_data

 

Returns

the GstVideoGLTextureUploadMeta on buffer .


gst_buffer_get_video_gl_texture_upload_meta()

#define gst_buffer_get_video_gl_texture_upload_meta(b) ((GstVideoGLTextureUploadMeta*)gst_buffer_get_meta((b),GST_VIDEO_GL_TEXTURE_UPLOAD_META_API_TYPE))

gst_video_gl_texture_upload_meta_upload ()

gboolean
gst_video_gl_texture_upload_meta_upload
                               (GstVideoGLTextureUploadMeta *meta,
                                guint texture_id[4]);

Uploads the buffer which owns the meta to a specific texture ID.

Parameters

meta

a GstVideoGLTextureUploadMeta

 

texture_id

the texture IDs to upload to

 

Returns

TRUE if uploading succeeded, FALSE otherwise.

Types and Values

struct GstVideoMeta

struct GstVideoMeta {
  GstMeta            meta;

  GstBuffer         *buffer;

  GstVideoFrameFlags flags;
  GstVideoFormat     format;
  gint               id;
  guint              width;
  guint              height;

  guint              n_planes;
  gsize              offset[GST_VIDEO_MAX_PLANES];
  gint               stride[GST_VIDEO_MAX_PLANES];

  gboolean (*map)    (GstVideoMeta *meta, guint plane, GstMapInfo *info,
                      gpointer *data, gint * stride, GstMapFlags flags);
  gboolean (*unmap)  (GstVideoMeta *meta, guint plane, GstMapInfo *info);
};

Extra buffer metadata describing image properties

Members

GstMeta meta;

parent GstMeta

 

GstBuffer *buffer;

the buffer this metadata belongs to

 

GstVideoFrameFlags flags;

additional video flags

 

GstVideoFormat format;

the video format

 

gint id;

identifier of the frame

 

guint width;

the video width

 

guint height;

the video height

 

guint n_planes;

the number of planes in the image

 

gsize offset[GST_VIDEO_MAX_PLANES];

array of offsets for the planes. This field might not always be valid, it is used by the default implementation of map .

 

gint stride[GST_VIDEO_MAX_PLANES];

array of strides for the planes. This field might not always be valid, it is used by the default implementation of map .

 

map ()

map the memory of a plane

 

unmap ()

unmap the memory of a plane

 

GstVideoMetaTransform

typedef struct {
  GstVideoInfo *in_info;
  GstVideoInfo *out_info;
} GstVideoMetaTransform;

Extra data passed to a video transform GstMetaTransformFunction such as: "gst-video-scale".

Members

GstVideoInfo *in_info;

the input GstVideoInfo

 

GstVideoInfo *out_info;

the output GstVideoInfo

 

struct GstVideoCropMeta

struct GstVideoCropMeta {
  GstMeta       meta;

  guint         x;
  guint         y;
  guint         width;
  guint         height;
};

Extra buffer metadata describing image cropping.

Members

GstMeta meta;

parent GstMeta

 

guint x;

the horizontal offset

 

guint y;

the vertical offset

 

guint width;

the cropped width

 

guint height;

the cropped height

 

GstVideoRegionOfInterestMeta

typedef struct {
  GstMeta meta;

  GQuark roi_type;
  gint id;
  gint parent_id;

  guint x;
  guint y;
  guint w;
  guint h;
} GstVideoRegionOfInterestMeta;

Extra buffer metadata describing an image region of interest

Members

GstMeta meta;

parent GstMeta

 

GQuark roi_type;

GQuark describing the semantic of the Roi (f.i. a face, a pedestrian)

 

gint id;

identifier of this particular ROI

 

gint parent_id;

identifier of its parent ROI, used f.i. for ROI hierarchisation.

 

guint x;

x component of upper-left corner

 

guint y;

y component of upper-left corner

 

guint w;

   

guint h;

   

struct GstVideoGLTextureUploadMeta

struct GstVideoGLTextureUploadMeta {
  GstMeta       meta;

  GstVideoGLTextureOrientation texture_orientation;
  guint n_textures;
  GstVideoGLTextureType texture_type[4];
};

Extra buffer metadata for uploading a buffer to an OpenGL texture ID. The caller of gst_video_gl_texture_upload_meta_upload() must have OpenGL set up and call this from a thread where it is valid to upload something to an OpenGL texture.

Members

GstMeta meta;

parent GstMeta

 

GstVideoGLTextureOrientation texture_orientation;

Orientation of the textures

 

guint n_textures;

Number of textures that are generated

 

GstVideoGLTextureType texture_type[4];

Type of each texture