AVSphericalMapping Struct Reference

This structure describes how to handle spherical videos, outlining information about projection, initial layout, and any other view modifier. More...

#include <spherical.h>

Public Attributes
enum AVSphericalProjection	projection
	Projection type.
uint32_t	padding
	Number of pixels to pad from the edge of each cube face. More...
Initial orientation
There fields describe additional rotations applied to the sphere after the video frame is mapped onto it. The sphere is rotated around the viewer, who remains stationary. The order of transformation is always yaw, followed by pitch, and finally by roll. The coordinate system matches the one defined in OpenGL, where the forward vector (z) is coming out of screen, and it is equivalent to a rotation matrix of R = r_y(yaw) * r_x(pitch) * r_z(roll). A positive yaw rotates the portion of the sphere in front of the viewer toward their right. A positive pitch rotates the portion of the sphere in front of the viewer upwards. A positive roll tilts the portion of the sphere in front of the viewer to the viewer's right. These values are exported as 16.16 fixed point. See this equirectangular projection as example: Yaw -180 0 180 90 +-------------+-------------+ 180 | | | up P | | | y| forward i | ^ | | /z t 0 +-------------X-------------+ 0 Roll | / c | | | | / h | | | 0|/_____right | | | x -90 +-------------+-------------+ -180 X - the default camera center ^ - the default up vector
int32_t	yaw
	Rotation around the up vector [-180, 180].
int32_t	pitch
	Rotation around the right vector [-90, 90].
int32_t	roll
	Rotation around the forward vector [-180, 180].
Bounding rectangle
These fields indicate the location of the current tile, and where it should be mapped relative to the original surface. They are exported as 0.32 fixed point, and can be converted to classic pixel values with av_spherical_bounds(). +----------------+----------+ | |bound_top | | +--------+ | | bound_left |tile | | +<---------->| |<--->+bound_right | +--------+ | | | | | bound_bottom| | +----------------+----------+ If needed, the original video surface dimensions can be derived by adding the current stream or frame size to the related bounds, like in the following example: original_width = tile->width + bound_left + bound_right; original_height = tile->height + bound_top + bound_bottom; Note These values are valid only for the tiled equirectangular projection type (AV_SPHERICAL_EQUIRECTANGULAR_TILE), and should be ignored in all other cases.
uint32_t	bound_left
	Distance from the left edge.
uint32_t	bound_top
	Distance from the top edge.
uint32_t	bound_right
	Distance from the right edge.
uint32_t	bound_bottom
	Distance from the bottom edge.

Detailed Description

This structure describes how to handle spherical videos, outlining information about projection, initial layout, and any other view modifier.

Note

The struct must be allocated with av_spherical_alloc() and its size is not a part of the public ABI.

Member Data Documentation

padding

uint32_t AVSphericalMapping::padding

Number of pixels to pad from the edge of each cube face.

Note

This value is valid for only for the cubemap projection type (AV_SPHERICAL_CUBEMAP), and should be ignored in all other cases.

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The documentation for this struct was generated from the following file:

• libavutil/spherical.h