GstVideoOverlayRectangle

GstVideoOverlayComposition

gst_video_overlay_composition_new

GstVideoOverlayComposition *
gst_video_overlay_composition_new (GstVideoOverlayRectangle * rectangle)

Creates a new video overlay composition object to hold one or more overlay rectangles.

Note that since 1.20 this allows to pass NULL for rectangle.

gst_video_overlay_composition_add_rectangle

gst_video_overlay_composition_add_rectangle (GstVideoOverlayComposition * comp,
                                             GstVideoOverlayRectangle * rectangle)

Adds an overlay rectangle to an existing overlay composition object. This must be done right after creating the overlay composition.

gst_video_overlay_composition_blend

gboolean
gst_video_overlay_composition_blend (GstVideoOverlayComposition * comp,
                                     GstVideoFrame * video_buf)

Blends the overlay rectangles in comp on top of the raw video data contained in video_buf. The data in video_buf must be writable and mapped appropriately.

Since video_buf data is read and will be modified, it ought be mapped with flag GST_MAP_READWRITE.

gst_video_overlay_composition_copy

GstVideoOverlayComposition *
gst_video_overlay_composition_copy (GstVideoOverlayComposition * comp)

Makes a copy of comp and all contained rectangles, so that it is possible to modify the composition and contained rectangles (e.g. add additional rectangles or change the render co-ordinates or render dimension). The actual overlay pixel data buffers contained in the rectangles are not copied.

gst_video_overlay_composition_get_rectangle

GstVideoOverlayRectangle *
gst_video_overlay_composition_get_rectangle (GstVideoOverlayComposition * comp,
                                             guint n)

Returns the n-th GstVideoOverlayRectangle contained in comp.

gst_video_overlay_composition_get_seqnum

guint
gst_video_overlay_composition_get_seqnum (GstVideoOverlayComposition * comp)

Returns the sequence number of this composition. Sequence numbers are monotonically increasing and unique for overlay compositions and rectangles (meaning there will never be a rectangle with the same sequence number as a composition).

gst_video_overlay_composition_make_writable

GstVideoOverlayComposition *
gst_video_overlay_composition_make_writable (GstVideoOverlayComposition * comp)

Takes ownership of comp and returns a version of comp that is writable (i.e. can be modified). Will either return comp right away, or create a new writable copy of comp and unref comp itself. All the contained rectangles will also be copied, but the actual overlay pixel data buffers contained in the rectangles are not copied.

gst_video_overlay_composition_n_rectangles

guint
gst_video_overlay_composition_n_rectangles (GstVideoOverlayComposition * comp)

Returns the number of GstVideoOverlayRectangles contained in comp.

GstVideoOverlayCompositionMeta

gst_video_overlay_composition_meta_get_info

const GstMetaInfo *
gst_video_overlay_composition_meta_get_info ()

GstVideoOverlayRectangle

gst_video_overlay_rectangle_new_raw

GstVideoOverlayRectangle *
gst_video_overlay_rectangle_new_raw (GstBuffer * pixels,
                                     gint render_x,
                                     gint render_y,
                                     guint render_width,
                                     guint render_height,
                                     GstVideoOverlayFormatFlags flags)

Creates a new video overlay rectangle with ARGB or AYUV pixel data. The layout in case of ARGB of the components in memory is B-G-R-A on little-endian platforms (corresponding to GST_VIDEO_FORMAT_BGRA) and A-R-G-B on big-endian platforms (corresponding to GST_VIDEO_FORMAT_ARGB). In other words, pixels are treated as 32-bit words and the lowest 8 bits then contain the blue component value and the highest 8 bits contain the alpha component value. Unless specified in the flags, the RGB values are non-premultiplied. This is the format that is used by most hardware, and also many rendering libraries such as Cairo, for example. The pixel data buffer must have GstVideoMeta set.

gst_video_overlay_rectangle_copy

GstVideoOverlayRectangle *
gst_video_overlay_rectangle_copy (GstVideoOverlayRectangle * rectangle)

Makes a copy of rectangle, so that it is possible to modify it (e.g. to change the render co-ordinates or render dimension). The actual overlay pixel data buffers contained in the rectangle are not copied.

gst_video_overlay_rectangle_get_flags

GstVideoOverlayFormatFlags
gst_video_overlay_rectangle_get_flags (GstVideoOverlayRectangle * rectangle)

Retrieves the flags associated with a GstVideoOverlayRectangle. This is useful if the caller can handle both premultiplied alpha and non premultiplied alpha, for example. By knowing whether the rectangle uses premultiplied or not, it can request the pixel data in the format it is stored in, to avoid unnecessary conversion.

gst_video_overlay_rectangle_get_global_alpha

gfloat
gst_video_overlay_rectangle_get_global_alpha (GstVideoOverlayRectangle * rectangle)

Retrieves the global-alpha value associated with a GstVideoOverlayRectangle.

gst_video_overlay_rectangle_get_pixels_argb

GstBuffer *
gst_video_overlay_rectangle_get_pixels_argb (GstVideoOverlayRectangle * rectangle,
                                             GstVideoOverlayFormatFlags flags)

gst_video_overlay_rectangle_get_pixels_ayuv

GstBuffer *
gst_video_overlay_rectangle_get_pixels_ayuv (GstVideoOverlayRectangle * rectangle,
                                             GstVideoOverlayFormatFlags flags)

gst_video_overlay_rectangle_get_pixels_raw

GstBuffer *
gst_video_overlay_rectangle_get_pixels_raw (GstVideoOverlayRectangle * rectangle,
                                            GstVideoOverlayFormatFlags flags)

gst_video_overlay_rectangle_get_pixels_unscaled_argb

GstBuffer *
gst_video_overlay_rectangle_get_pixels_unscaled_argb (GstVideoOverlayRectangle * rectangle,
                                                      GstVideoOverlayFormatFlags flags)

Retrieves the pixel data as it is. This is useful if the caller can do the scaling itself when handling the overlaying. The rectangle will need to be scaled to the render dimensions, which can be retrieved using gst_video_overlay_rectangle_get_render_rectangle.

gst_video_overlay_rectangle_get_pixels_unscaled_ayuv

GstBuffer *
gst_video_overlay_rectangle_get_pixels_unscaled_ayuv (GstVideoOverlayRectangle * rectangle,
                                                      GstVideoOverlayFormatFlags flags)

Retrieves the pixel data as it is. This is useful if the caller can do the scaling itself when handling the overlaying. The rectangle will need to be scaled to the render dimensions, which can be retrieved using gst_video_overlay_rectangle_get_render_rectangle.

gst_video_overlay_rectangle_get_pixels_unscaled_raw

GstBuffer *
gst_video_overlay_rectangle_get_pixels_unscaled_raw (GstVideoOverlayRectangle * rectangle,
                                                     GstVideoOverlayFormatFlags flags)

Retrieves the pixel data as it is. This is useful if the caller can do the scaling itself when handling the overlaying. The rectangle will need to be scaled to the render dimensions, which can be retrieved using gst_video_overlay_rectangle_get_render_rectangle.

gst_video_overlay_rectangle_get_render_rectangle

gboolean
gst_video_overlay_rectangle_get_render_rectangle (GstVideoOverlayRectangle * rectangle,
                                                  gint * render_x,
                                                  gint * render_y,
                                                  guint * render_width,
                                                  guint * render_height)

Retrieves the render position and render dimension of the overlay rectangle on the video.

gst_video_overlay_rectangle_get_seqnum

guint
gst_video_overlay_rectangle_get_seqnum (GstVideoOverlayRectangle * rectangle)

Returns the sequence number of this rectangle. Sequence numbers are monotonically increasing and unique for overlay compositions and rectangles (meaning there will never be a rectangle with the same sequence number as a composition).

Using the sequence number of a rectangle as an indicator for changed pixel-data of a rectangle is dangereous. Some API calls, like e.g. gst_video_overlay_rectangle_set_global_alpha, automatically update the per rectangle sequence number, which is misleading for renderers/ consumers, that handle global-alpha themselves. For them the pixel-data returned by gst_video_overlay_rectangle_get_pixels_*() won't be different for different global-alpha values. In this case a renderer could also use the GstBuffer pointers as a hint for changed pixel-data.

gst_video_overlay_rectangle_set_global_alpha

gst_video_overlay_rectangle_set_global_alpha (GstVideoOverlayRectangle * rectangle,
                                              gfloat global_alpha)

Sets the global alpha value associated with a GstVideoOverlayRectangle. Per- pixel alpha values are multiplied with this value. Valid values: 0 <= global_alpha <= 1; 1 to deactivate.

rectangle must be writable, meaning its refcount must be 1. You can make the rectangles inside a GstVideoOverlayComposition writable using gst_video_overlay_composition_make_writable or gst_video_overlay_composition_copy.

gst_video_overlay_rectangle_set_render_rectangle

gst_video_overlay_rectangle_set_render_rectangle (GstVideoOverlayRectangle * rectangle,
                                                  gint render_x,
                                                  gint render_y,
                                                  guint render_width,
                                                  guint render_height)

Sets the render position and dimensions of the rectangle on the video. This function is mainly for elements that modify the size of the video in some way (e.g. through scaling or cropping) and need to adjust the details of any overlays to match the operation that changed the size.

rectangle must be writable, meaning its refcount must be 1. You can make the rectangles inside a GstVideoOverlayComposition writable using gst_video_overlay_composition_make_writable or gst_video_overlay_composition_copy.

gst_buffer_add_video_overlay_composition_meta

GstVideoOverlayCompositionMeta *
gst_buffer_add_video_overlay_composition_meta (GstBuffer * buf,
                                               GstVideoOverlayComposition * comp)

Sets an overlay composition on a buffer. The buffer will obtain its own reference to the composition, meaning this function does not take ownership of comp.

gst_video_overlay_composition_meta_api_get_type

GType
gst_video_overlay_composition_meta_api_get_type ()

GST_VIDEO_OVERLAY_COMPOSITION_CAST

#define GST_VIDEO_OVERLAY_COMPOSITION_CAST(obj)			\
  ((GstVideoOverlayComposition *)(obj))

GST_VIDEO_OVERLAY_RECTANGLE_CAST

#define GST_VIDEO_OVERLAY_RECTANGLE_CAST(obj)			\
  ((GstVideoOverlayRectangle *)(obj))

gst_buffer_get_video_overlay_composition_meta

#define gst_buffer_get_video_overlay_composition_meta(b) \
  ((GstVideoOverlayCompositionMeta*)gst_buffer_get_meta((b),GST_VIDEO_OVERLAY_COMPOSITION_META_API_TYPE))

gst_buffer_remove_video_overlay_composition_meta

#define gst_buffer_remove_video_overlay_composition_meta(b,m) \
  gst_buffer_remove_meta((b),((GstMeta *) m))

GstVideoOverlayFormatFlags

Overlay format flags.

GST_CAPS_FEATURE_META_GST_VIDEO_OVERLAY_COMPOSITION

#define GST_CAPS_FEATURE_META_GST_VIDEO_OVERLAY_COMPOSITION "meta:GstVideoOverlayComposition"

GST_TYPE_VIDEO_OVERLAY_COMPOSITION

#define GST_TYPE_VIDEO_OVERLAY_COMPOSITION			\
  (gst_video_overlay_composition_get_type ())

GST_TYPE_VIDEO_OVERLAY_RECTANGLE

#define GST_TYPE_VIDEO_OVERLAY_RECTANGLE			\
  (gst_video_overlay_rectangle_get_type ())

GST_VIDEO_OVERLAY_COMPOSITION_BLEND_FORMATS

#define GST_VIDEO_OVERLAY_COMPOSITION_BLEND_FORMATS GST_VIDEO_FORMATS_ALL

Video formats supported by gst_video_overlay_composition_blend, for use in overlay elements' pad template caps.

Since : 1.2

GST_VIDEO_OVERLAY_COMPOSITION_FORMAT_RGB

#define GST_VIDEO_OVERLAY_COMPOSITION_FORMAT_RGB      GST_VIDEO_FORMAT_BGRA

Supported RGB overlay video format.

GST_VIDEO_OVERLAY_COMPOSITION_FORMAT_YUV

#define GST_VIDEO_OVERLAY_COMPOSITION_FORMAT_YUV      GST_VIDEO_FORMAT_AYUV

Supported YUV overlay video format.

GST_VIDEO_OVERLAY_COMPOSITION_META_API_TYPE

#define GST_VIDEO_OVERLAY_COMPOSITION_META_API_TYPE \
    (gst_video_overlay_composition_meta_api_get_type())

GST_VIDEO_OVERLAY_COMPOSITION_META_INFO

#define GST_VIDEO_OVERLAY_COMPOSITION_META_INFO \
    (gst_video_overlay_composition_meta_get_info())