libcamera  v0.3.0
Supporting cameras in Linux since 2019
agc_mean_luminance.h
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1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2 /*
3  * Copyright (C) 2024 Ideas on Board Oy
4  *
5  agc_mean_luminance.h - Base class for mean luminance AGC algorithms
6  */
7 
8 #pragma once
9 
10 #include <map>
11 #include <memory>
12 #include <tuple>
13 #include <vector>
14 
15 #include <libcamera/controls.h>
16 
18 
19 #include "exposure_mode_helper.h"
20 #include "histogram.h"
21 
22 namespace libcamera {
23 
24 namespace ipa {
25 
27 {
28 public:
30  virtual ~AgcMeanLuminance();
31 
32  struct AgcConstraint {
33  enum class Bound {
34  lower = 0,
35  upper = 1
36  };
38  double qLo;
39  double qHi;
40  double yTarget;
41  };
42 
43  int parseTuningData(const YamlObject &tuningData);
44 
45  void setLimits(utils::Duration minShutter, utils::Duration maxShutter,
46  double minGain, double maxGain);
47 
48  std::map<int32_t, std::vector<AgcConstraint>> constraintModes()
49  {
50  return constraintModes_;
51  }
52 
53  std::map<int32_t, std::shared_ptr<ExposureModeHelper>> exposureModeHelpers()
54  {
55  return exposureModeHelpers_;
56  }
57 
59  {
60  return controls_;
61  }
62 
63  std::tuple<utils::Duration, double, double>
64  calculateNewEv(uint32_t constraintModeIndex, uint32_t exposureModeIndex,
65  const Histogram &yHist, utils::Duration effectiveExposureValue);
66 
68  {
69  frameCount_ = 0;
70  }
71 
72 private:
73  virtual double estimateLuminance(const double gain) const = 0;
74 
75  void parseRelativeLuminanceTarget(const YamlObject &tuningData);
76  void parseConstraint(const YamlObject &modeDict, int32_t id);
77  int parseConstraintModes(const YamlObject &tuningData);
78  int parseExposureModes(const YamlObject &tuningData);
79  double estimateInitialGain() const;
80  double constraintClampGain(uint32_t constraintModeIndex,
81  const Histogram &hist,
82  double gain);
83  utils::Duration filterExposure(utils::Duration exposureValue);
84 
85  uint64_t frameCount_;
86  utils::Duration filteredExposure_;
87  double relativeLuminanceTarget_;
88 
89  std::map<int32_t, std::vector<AgcConstraint>> constraintModes_;
90  std::map<int32_t, std::shared_ptr<ExposureModeHelper>> exposureModeHelpers_;
91  ControlInfoMap::Map controls_;
92 };
93 
94 } /* namespace ipa */
95 
96 } /* namespace libcamera */
std::unordered_map< const ControlId *, ControlInfo > Map
The base std::unsorted_map<> container.
Definition: controls.h:308
A class representing the tree structure of the YAML content.
Definition: yaml_parser.h:26
A mean-based auto-exposure algorithm.
Definition: agc_mean_luminance.h:27
void setLimits(utils::Duration minShutter, utils::Duration maxShutter, double minGain, double maxGain)
Set the ExposureModeHelper limits for this class.
Definition: agc_mean_luminance.cpp:382
void resetFrameCount()
Reset the frame counter.
Definition: agc_mean_luminance.h:67
std::map< int32_t, std::vector< AgcConstraint > > constraintModes()
Get the constraint modes that have been parsed from tuning data.
Definition: agc_mean_luminance.h:48
int parseTuningData(const YamlObject &tuningData)
Parse tuning data for AeConstraintMode and AeExposureMode controls.
Definition: agc_mean_luminance.cpp:359
ControlInfoMap::Map controls()
Get the controls that have been generated after parsing tuning data.
Definition: agc_mean_luminance.h:58
std::tuple< utils::Duration, double, double > calculateNewEv(uint32_t constraintModeIndex, uint32_t exposureModeIndex, const Histogram &yHist, utils::Duration effectiveExposureValue)
Calculate the new exposure value and splut it between shutter time and gain.
Definition: agc_mean_luminance.cpp:531
std::map< int32_t, std::shared_ptr< ExposureModeHelper > > exposureModeHelpers()
Get the ExposureModeHelpers that have been parsed from tuning data.
Definition: agc_mean_luminance.h:53
The base class for creating histograms.
Definition: histogram.h:24
Helper class from std::chrono::duration that represents a time duration in nanoseconds with double pr...
Definition: utils.h:330
Framework to manage controls related to an object.
Helper class that performs computations relating to exposure.
Class to represent Histograms and manipulate them.
Top-level libcamera namespace.
Definition: backtrace.h:17
The boundaries and target for an AeConstraintMode constraint.
Definition: agc_mean_luminance.h:32
double qHi
The upper quantile to use for the constraint.
Definition: agc_mean_luminance.h:39
Bound
Specify whether the constraint defines a lower or upper bound.
Definition: agc_mean_luminance.h:33
@ upper
The constraint defines an upper bound.
@ lower
The constraint defines a lower bound.
double qLo
The lower quantile to use for the constraint.
Definition: agc_mean_luminance.h:38
Bound bound
The type of constraint bound.
Definition: agc_mean_luminance.h:37
double yTarget
The luminance target for the constraint.
Definition: agc_mean_luminance.h:40
A YAML parser helper.