u_autoexpgain.h File Reference

Automatically compute exposure and gain values from an image stream. More...

#include "xrt/xrt_frame.h"
#include <stdint.h>

Include dependency graph for u_autoexpgain.h:

Go to the source code of this file.

Data Structures
struct	u_aeg_step
	These are steps for constructing a piecewise linear function that maps brightness into (exposure, gain) pairs. More...

Macros
#define	U_AEG_MAX_STEPS   16
	Most steps a custom table passed to u_autoexpgain_create_with_steps can have.

Enumerations
enum	u_aeg_strategy { U_AEG_STRATEGY_TRACKING = 0 , U_AEG_STRATEGY_DYNAMIC_RANGE , U_AEG_STRATEGY_COUNT }
	An auto exposure/gain strategy tunes the algorithm for specific objectives. More...

Functions
struct u_autoexpgain *	u_autoexpgain_create (enum u_aeg_strategy strategy, bool enabled_from_start, int frame_delay)
	Create auto exposure and gain (AEG) algorithm object.
struct u_autoexpgain *	u_autoexpgain_create_with_steps (enum u_aeg_strategy strategy, bool enabled_from_start, int frame_delay, const struct u_aeg_step *steps, int step_count)
	Create auto exposure and gain (AEG) algorithm object.
void	u_autoexpgain_add_vars (struct u_autoexpgain *aeg, void *root, char *prefix)
	Setup UI for the AEG algorithm.
void	u_autoexpgain_update (struct u_autoexpgain *aeg, struct xrt_frame *xf)
	Update the AEG with a frame.
float	u_autoexpgain_get_exposure (struct u_autoexpgain *aeg)
	Get currently computed exposure value in usecs.
float	u_autoexpgain_get_gain (struct u_autoexpgain *aeg)
	Get currently computed gain value.
void	u_autoexpgain_destroy (struct u_autoexpgain **aeg)
	Destroy AEG object.

Detailed Description

Automatically compute exposure and gain values from an image stream.

Author

Mateo de Mayo mateo.nosp@m..dem.nosp@m.ayo@c.nosp@m.olla.nosp@m.bora..nosp@m.com

Macro Definition Documentation

U_AEG_MAX_STEPS

#define U_AEG_MAX_STEPS   16

Most steps a custom table passed to u_autoexpgain_create_with_steps can have.

Enumeration Type Documentation

u_aeg_strategy

enum u_aeg_strategy

An auto exposure/gain strategy tunes the algorithm for specific objectives.

Enumerator
U_AEG_STRATEGY_TRACKING	Lower exposure and gain at the cost of darker images.
U_AEG_STRATEGY_DYNAMIC_RANGE	Tries to maximize the image information.

Function Documentation

u_autoexpgain_add_vars()

void u_autoexpgain_add_vars	(	struct u_autoexpgain *	aeg,
		void *	root,
		char *	prefix
	)

Setup UI for the AEG algorithm.

References u_autoexpgain::brightness, u_autoexpgain::current_score, u_autoexpgain::enable, u_autoexpgain::frame_delay, u_autoexpgain::histogram_ui, u_autoexpgain::max_brightness_step, u_autoexpgain::strategy_combo, and u_autoexpgain::threshold.

Referenced by rift_s_camera_create().

u_autoexpgain_create()

struct u_autoexpgain * u_autoexpgain_create	(	enum u_aeg_strategy	strategy,
		bool	enabled_from_start,
		int	frame_delay
	)

Create auto exposure and gain (AEG) algorithm object.

Parameters

strategy	What objective is preferred for the algorithm.
enabled_from_start	Update exposure/gain from the start.
frame_delay	About how many frames does it take for exp and gain to settle in.

Returns

struct u_autoexpgain* Created object

References u_autoexpgain::brightness, brightness_to_expgain(), u_var_combo::count, u_var_histogram_f32::count, u_autoexpgain::enable, u_autoexpgain::exposure, u_autoexpgain::frame_delay, u_autoexpgain::gain, u_autoexpgain::histogram, u_autoexpgain::histogram_ui, u_autoexpgain::last_brightness, LEVELS, u_autoexpgain::max_brightness_step, u_var_combo::options, u_autoexpgain::overshoots, u_autoexpgain::state, u_autoexpgain::strategy, u_autoexpgain::strategy_combo, u_autoexpgain::threshold, U_TYPED_CALLOC, u_var_combo::value, u_var_histogram_f32::values, and u_autoexpgain::wait.

Referenced by rift_s_camera_create(), and u_autoexpgain_create_with_steps().

u_autoexpgain_create_with_steps()

struct u_autoexpgain * u_autoexpgain_create_with_steps	(	enum u_aeg_strategy	strategy,
		bool	enabled_from_start,
		int	frame_delay,
		const struct u_aeg_step *	steps,
		int	step_count
	)

Create auto exposure and gain (AEG) algorithm object.

Parameters

strategy	What objective is preferred for the algorithm.
enabled_from_start	Update exposure/gain from the start.
frame_delay	About how many frames does it take for exp and gain to settle in.

Returns

struct u_autoexpgain* Created object

Parameters

steps	Brightness ascending, from 0 to 1; copied.
step_count	Between 2 and U_AEG_MAX_STEPS.

References u_autoexpgain::brightness, brightness_to_expgain(), u_autoexpgain::exposure, u_autoexpgain::frame_delay, u_autoexpgain::gain, u_autoexpgain::steps, u_autoexpgain::strategy, U_AEG_MAX_STEPS, and u_autoexpgain_create().

u_autoexpgain_destroy()

void u_autoexpgain_destroy

(

struct u_autoexpgain **

aeg

)

Destroy AEG object.

u_autoexpgain_get_exposure()

float u_autoexpgain_get_exposure

(

struct u_autoexpgain *

aeg

)

Get currently computed exposure value in usecs.

References u_autoexpgain::exposure.

Referenced by update_expgain().

u_autoexpgain_get_gain()

float u_autoexpgain_get_gain

(

struct u_autoexpgain *

aeg

)

Get currently computed gain value.

References u_autoexpgain::gain.

Referenced by update_expgain().

u_autoexpgain_update()

void u_autoexpgain_update	(	struct u_autoexpgain *	aeg,
		struct xrt_frame *	xf
	)

Update the AEG with a frame.

References update_expgain().

Referenced by update_expgain().