GstVideoAffineTransformationMeta

GstVideoAffineTransformationMeta — GstMeta for video affine transformation

Functions

Types and Values

Includes

#include <gst/video/video.h>

Description

Functions

GstVideoAffineTransformationGetMatrix ()

gboolean
(*GstVideoAffineTransformationGetMatrix)
                               (GstVideoAffineTransformationMeta *meta,
                                gfloat *matrix);

gst_buffer_add_video_affine_transformation_meta ()

GstVideoAffineTransformationMeta *
gst_buffer_add_video_affine_transformation_meta
                               (GstBuffer *buffer);

Attaches GstVideoAffineTransformationMeta metadata to buffer with the given parameters.

Parameters

buffer

a GstBuffer

 

Returns

the GstVideoAffineTransformationMeta on buffer .

[transfer none]

Since: 1.8


gst_buffer_get_video_affine_transformation_meta()

#define             gst_buffer_get_video_affine_transformation_meta(b)

gst_video_affine_transformation_meta_apply_matrix ()

void
gst_video_affine_transformation_meta_apply_matrix
                               (GstVideoAffineTransformationMeta *meta,
                                const gfloat matrix[16]);

Apply a transformation using the given 4x4 transformation matrix. Performs the multiplication, meta->matrix X matrix.

Parameters

meta

a GstVideoAffineTransformationMeta

 

matrix

a 4x4 transformation matrix to be applied

 

Since: 1.8

Types and Values

struct GstVideoAffineTransformationMeta

struct GstVideoAffineTransformationMeta {
  GstMeta meta;

  gfloat matrix[16];
};

Extra buffer metadata for performing an affine transformation using a 4x4 matrix. The transformation matrix can be composed with gst_video_affine_transformation_meta_apply_matrix().

The vertices operated on are all in the range 0 to 1, not in Normalized Device Coordinates (-1 to +1). Transforming points in this space are assumed to have an origin at (0.5, 0.5, 0.5) in a left-handed coordinate system with the x-axis moving horizontally (positive values to the right), the y-axis moving vertically (positive values up the screen) and the z-axis perpendicular to the screen (positive values into the screen).

Members

GstMeta meta;

parent GstMeta

 

gfloat matrix[16];

the column-major 4x4 transformation matrix

 

Since: 1.8


GST_BUFFER_POOL_OPTION_VIDEO_AFFINE_TRANSFORMATION_META

#define GST_BUFFER_POOL_OPTION_VIDEO_AFFINE_TRANSFORMATION_META "GstBufferPoolOptionVideoAffineTransformation"