t_camera_models.h File Reference

Simple, untemplated, C, float-only, camera (un)projection functions for various camera models. More...

#include "math/m_vec2.h"
#include "math/m_matrix_2x2.h"
#include "math/m_mathinclude.h"
#include "t_tracking.h"
#include <assert.h>

Include dependency graph for t_camera_models.h:

Go to the source code of this file.

Data Structures
struct	t_camera_calibration_kb4_params_float
	Floating point parameters for T_DISTORTION_FISHEYE_KB4. More...
struct	t_camera_calibration_rt8_params_float
	Floating point parameters for T_DISTORTION_OPENCV_RT8, also including metric_radius. More...
struct	t_camera_model_params
	Floating point calibration data for a single calibrated camera. More...

Functions
static float	kb4_calc_r_theta (const struct t_camera_model_params *dist, const float theta, const float theta2)
static bool	kb4_project (const struct t_camera_model_params *dist, const float x, const float y, const float z, float *out_x, float *out_y)
static float	kb4_solve_theta (const struct t_camera_model_params *dist, const float *r_theta, float *d_func_d_theta)
static bool	kb4_unproject (const struct t_camera_model_params *dist, const float x, const float y, float *out_x, float *out_y, float *out_z)
static void	kb4_undistort (const struct t_camera_model_params *dist, const float x, const float y, float *out_x, float *out_y)
static bool	rt8_project (const struct t_camera_model_params *dist, const float x, const float y, const float z, float *out_x, float *out_y)
static void	rt8_distort (const struct t_camera_model_params *params, const struct xrt_vec2 *undist, struct xrt_vec2 *dist, struct xrt_matrix_2x2 *d_dist_d_undist)
static void	rt8_undistort (const struct t_camera_model_params *hg_dist, const float u, const float v, float *out_x, float *out_y)
static bool	rt8_unproject (const struct t_camera_model_params *hg_dist, const float u, const float v, float *out_x, float *out_y, float *out_z)
static void	interpret_as_rt8 (const struct t_camera_calibration *cc, struct t_camera_model_params *out_params)
static void	t_camera_model_params_from_t_camera_calibration (const struct t_camera_calibration *cc, struct t_camera_model_params *out_params)
	Takes a t_camera_calibration through cc, and returns a t_camera_model_params that shadows cc 's parameters through out_params. More...
static bool	t_camera_models_unproject (const struct t_camera_model_params *dist, const float x, const float y, float *out_x, float *out_y, float *out_z)
	Takes a 2D image-space point through x and y, unprojects it to a normalized 3D direction, and returns the result through out_x, out_y and out_z. More...
static bool	t_camera_models_unproject_and_flip (const struct t_camera_model_params *dist, const float x, const float y, float *out_x, float *out_y, float *out_z)
	Takes a 2D image-space point through x and y, unprojects it to a normalized 3D direction, flips its Y and Z values (performing a coordinate space transform from +Z forward -Y up to -Z forward +Y up) and returns the result through out_x, out_y and out_z. More...
static void	t_camera_models_undistort (const struct t_camera_model_params *dist, const float x, const float y, float *out_x, float *out_y)
	Takes a distorted 2D point through x and y and computes the undistorted point into out_x and out_y. More...
static bool	t_camera_models_project (const struct t_camera_model_params *dist, const float x, const float y, const float z, float *out_x, float *out_y)
	Takes a 3D point through x, y, and z, projects it into image space, and returns the result through out_x and out_y. More...
static bool	t_camera_models_flip_and_project (const struct t_camera_model_params *dist, const float x, const float y, const float z, float *out_x, float *out_y)
	Takes a 3D point through x, y, and z, flips its Y and Z values (performing a coordinate space transform from -Z forward +Y up to +Z forward -Y up), projects it into image space, and returns the result through out_x and out_y. More...

Variables
static const float	SQRT_EPSILON = 0.00316

Detailed Description

Simple, untemplated, C, float-only, camera (un)projection functions for various camera models.

Author

Moses Turner moses.nosp@m.@col.nosp@m.labor.nosp@m.a.co.nosp@m.m

Some notes: These functions should return exactly the same values as basalt-headers, down to floating point bits.

They were mainly written as an expedient way to stop depending on OpenCV-based (un)projection code in Monado's hand tracking code, and to encourage compiler optimizations through inlining.

Current users:

• Mercury hand tracking

Function Documentation

kb4_unproject()

static bool kb4_unproject ( const struct t_camera_model_params *  dist, const float  x, const float  y, float *  out_x, float *  out_y, float *  out_z  )

inlinestatic

Todo:

I'm not 100% sure if kb4 is always non-injective. basalt-headers always returns true here, so it might be wrong too.

rt8_undistort()

static void rt8_undistort ( const struct t_camera_model_params *  hg_dist, const float  u, const float  v, float *  out_x, float *  out_y  )

inlinestatic

Todo:

Decide if besides rpmax, it could be useful to have an rppmax field. A good starting point to having this would be using the sqrt of the max rpp2 value computed in the optimization of computeRpmax().

Referenced by t_camera_models_undistort().

t_camera_model_params_from_t_camera_calibration()

static void t_camera_model_params_from_t_camera_calibration ( const struct t_camera_calibration *  cc, struct t_camera_model_params *  out_params  )

inlinestatic

Takes a t_camera_calibration through cc, and returns a t_camera_model_params that shadows cc 's parameters through out_params.

References t_camera_calibration::distortion_model, t_camera_calibration::intrinsics, T_DISTORTION_FISHEYE_KB4, T_DISTORTION_OPENCV_RADTAN_14, T_DISTORTION_OPENCV_RADTAN_5, T_DISTORTION_OPENCV_RADTAN_8, T_DISTORTION_WMR, and U_ZERO.

t_camera_models_flip_and_project()

static bool t_camera_models_flip_and_project ( const struct t_camera_model_params *  dist, const float  x, const float  y, const float  z, float *  out_x, float *  out_y  )

inlinestatic

Takes a 3D point through x, y, and z, flips its Y and Z values (performing a coordinate space transform from -Z forward +Y up to +Z forward -Y up), projects it into image space, and returns the result through out_x and out_y.

References t_camera_models_project().

t_camera_models_project()

static bool t_camera_models_project ( const struct t_camera_model_params *  dist, const float  x, const float  y, const float  z, float *  out_x, float *  out_y  )

inlinestatic

Takes a 3D point through x, y, and z, projects it into image space, and returns the result through out_x and out_y.

References T_DISTORTION_OPENCV_RADTAN_8.

Referenced by t_camera_models_flip_and_project().

t_camera_models_undistort()

static void t_camera_models_undistort ( const struct t_camera_model_params *  dist, const float  x, const float  y, float *  out_x, float *  out_y  )

inlinestatic

Takes a distorted 2D point through x and y and computes the undistorted point into out_x and out_y.

References rt8_undistort(), T_DISTORTION_FISHEYE_KB4, and T_DISTORTION_OPENCV_RADTAN_8.

t_camera_models_unproject()

static bool t_camera_models_unproject ( const struct t_camera_model_params *  dist, const float  x, const float  y, float *  out_x, float *  out_y, float *  out_z  )

inlinestatic

Takes a 2D image-space point through x and y, unprojects it to a normalized 3D direction, and returns the result through out_x, out_y and out_z.

References T_DISTORTION_OPENCV_RADTAN_8.

Referenced by t_camera_models_unproject_and_flip().

t_camera_models_unproject_and_flip()

static bool t_camera_models_unproject_and_flip ( const struct t_camera_model_params *  dist, const float  x, const float  y, float *  out_x, float *  out_y, float *  out_z  )

inlinestatic

Takes a 2D image-space point through x and y, unprojects it to a normalized 3D direction, flips its Y and Z values (performing a coordinate space transform from +Z forward -Y up to -Z forward +Y up) and returns the result through out_x, out_y and out_z.

References t_camera_models_unproject().