summaryrefslogtreecommitdiff
path: root/test/serialization/control_serialization.cpp
blob: 2989b52774fbadc5a7b94dffe91d636f80e91927 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * Copyright (C) 2019, Google Inc.
 *
 * control_serialization.cpp - Serialize and deserialize controls
 */

#include <iostream>

#include <libcamera/camera.h>
#include <libcamera/control_ids.h>
#include <libcamera/controls.h>

#include "byte_stream_buffer.h"
#include "control_serializer.h"
#include "serialization_test.h"
#include "test.h"

using namespace std;
using namespace libcamera;

class ControlSerializationTest : public SerializationTest
{
protected:
	int init() override
	{
		return status_;
	}

	int run() override
	{
		ControlSerializer serializer;
		ControlSerializer deserializer;

		std::vector<uint8_t> infoData;
		std::vector<uint8_t> listData;

		size_t size;
		int ret;

		/* Create a control list with three controls. */
		const ControlInfoMap &infoMap = camera_->controls();
		ControlList list(infoMap);

		list.set(controls::Brightness, 255);
		list.set(controls::Contrast, 128);
		list.set(controls::Saturation, 50);

		/*
		 * Serialize the control list, this should fail as the control
		 * info map hasn't been serialized.
		 */
		size = serializer.binarySize(list);
		listData.resize(size);
		ByteStreamBuffer buffer(listData.data(), listData.size());

		ret = serializer.serialize(list, buffer);
		if (!ret) {
			cerr << "List serialization without info map should have failed"
			     << endl;
			return TestFail;
		}

		if (buffer.overflow() || buffer.offset()) {
			cerr << "Failed list serialization modified the buffer"
			     << endl;
			return TestFail;
		}

		/* Serialize the control info map. */
		size = serializer.binarySize(infoMap);
		infoData.resize(size);
		buffer = ByteStreamBuffer(infoData.data(), infoData.size());

		ret = serializer.serialize(infoMap, buffer);
		if (ret < 0) {
			cerr << "Failed to serialize ControlInfoMap" << endl;
			return TestFail;
		}

		if (buffer.overflow()) {
			cerr << "Overflow when serializing ControlInfoMap" << endl;
			return TestFail;
		}

		/* Serialize the control list, this should now succeed. */
		size = serializer.binarySize(list);
		listData.resize(size);
		buffer = ByteStreamBuffer(listData.data(), listData.size());

		ret = serializer.serialize(list, buffer);
		if (ret) {
			cerr << "Failed to serialize ControlList" << endl;
			return TestFail;
		}

		if (buffer.overflow()) {
			cerr << "Overflow when serializing ControlList" << endl;
			return TestFail;
		}

		/*
		 * Deserialize the control list, this should fail as the control
		 * info map hasn't been deserialized.
		 */
		buffer = ByteStreamBuffer(const_cast<const uint8_t *>(listData.data()),
					  listData.size());

		ControlList newList = deserializer.deserialize<ControlList>(buffer);
		if (!newList.empty()) {
			cerr << "List deserialization without info map should have failed"
			     << endl;
			return TestFail;
		}

		if (buffer.overflow()) {
			cerr << "Failed list deserialization modified the buffer"
			     << endl;
			return TestFail;
		}

		/* Deserialize the control info map and verify the contents. */
		buffer = ByteStreamBuffer(const_cast<const uint8_t *>(infoData.data()),
					  infoData.size());

		ControlInfoMap newInfoMap = deserializer.deserialize<ControlInfoMap>(buffer);
		if (newInfoMap.empty()) {
			cerr << "Failed to deserialize ControlInfoMap" << endl;
			return TestFail;
		}

		if (buffer.overflow()) {
			cerr << "Overflow when deserializing ControlInfoMap" << endl;
			return TestFail;
		}

		if (!equals(infoMap, newInfoMap)) {
			cerr << "Deserialized map doesn't match original" << endl;
			return TestFail;
		}

		/* Deserialize the control list and verify the contents. */
		buffer = ByteStreamBuffer(const_cast<const uint8_t *>(listData.data()),
					  listData.size());

		newList = deserializer.deserialize<ControlList>(buffer);
		if (newList.empty()) {
			cerr << "Failed to deserialize ControlList" << endl;
			return TestFail;
		}

		if (buffer.overflow()) {
			cerr << "Overflow when deserializing ControlList" << endl;
			return TestFail;
		}

		if (!equals(list, newList)) {
			cerr << "Deserialized list doesn't match original" << endl;
			return TestFail;
		}

		return TestPass;
	}
};

TEST_REGISTER(ControlSerializationTest)
n588' href='#n588'>588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789
/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
 * Copyright (C) 2021, Google Inc.
 *
 * Helper class that performs sensor-specific
 * parameter computations
 */
#include "camera_sensor_helper.h"

#include <cmath>
#include <limits>

#include <libcamera/base/log.h>

/**
 * \file camera_sensor_helper.h
 * \brief Helper class that performs sensor-specific parameter computations
 *
 * Computation of sensor configuration parameters is a sensor specific
 * operation. Each CameraHelper derived class computes the value of
 * configuration parameters, for example the analogue gain value, using
 * sensor-specific functions and constants.
 *
 * Every subclass of CameraSensorHelper shall be registered with libipa using
 * the REGISTER_CAMERA_SENSOR_HELPER() macro.
 */

namespace libcamera {

LOG_DEFINE_CATEGORY(CameraSensorHelper)

namespace ipa {

/**
 * \class CameraSensorHelper
 * \brief Base class for computing sensor tuning parameters using
 * sensor-specific constants
 *
 * Instances derived from CameraSensorHelper class are sensor-specific.
 * Each supported sensor will have an associated base class defined.
 */

/**
 * \fn CameraSensorHelper::CameraSensorHelper()
 * \brief Construct a CameraSensorHelper instance
 *
 * CameraSensorHelper derived class instances shall never be constructed
 * manually but always through the CameraSensorHelperFactoryBase::create()
 * function.
 */

/**
 * \fn CameraSensorHelper::blackLevel()
 * \brief Fetch the black level of the sensor
 *
 * This function returns the black level of the sensor scaled to a 16bit pixel
 * width. If it is unknown an empty optional is returned.
 *
 * \todo Fill the blanks and add pedestal values for all supported sensors. Once
 * done, drop the std::optional<>.
 *
 * Black levels are typically the result of the following phenomena:
 * - Pedestal added by the sensor to pixel values. They are typically fixed,
 *   sometimes programmable and should be reported in datasheets (but
 *   documentation is not always available).
 * - Dark currents and other physical effects that add charge to pixels in the
 *   absence of light. Those can depend on the integration time and the sensor
 *   die temperature, and their contribution to pixel values depend on the
 *   sensor gains.
 *
 * The pedestal is usually the value with the biggest contribution to the
 * overall black level. In most cases it is either known before or in rare cases
 * (there is not a single driver with such a control in the linux kernel) can be
 * queried from the sensor. This function provides that fixed, known value.
 *
 * \return The black level of the sensor, or std::nullopt if not known
 */

/**
 * \brief Compute gain code from the analogue gain absolute value
 * \param[in] gain The real gain to pass
 *
 * This function aims to abstract the calculation of the gain letting the IPA
 * use the real gain for its estimations.
 *
 * \return The gain code to pass to V4L2
 */
uint32_t CameraSensorHelper::gainCode(double gain) const
{
	const AnalogueGainConstants &k = gainConstants_;

	switch (gainType_) {
	case AnalogueGainLinear:
		ASSERT(k.linear.m0 == 0 || k.linear.m1 == 0);

		return (k.linear.c0 - k.linear.c1 * gain) /
		       (k.linear.m1 * gain - k.linear.m0);

	case AnalogueGainExponential:
		ASSERT(k.exp.a != 0 && k.exp.m != 0);

		return std::log2(gain / k.exp.a) / k.exp.m;

	default:
		ASSERT(false);
		return 0;
	}
}

/**
 * \brief Compute the real gain from the V4L2 subdev control gain code
 * \param[in] gainCode The V4L2 subdev control gain
 *
 * This function aims to abstract the calculation of the gain letting the IPA
 * use the real gain for its estimations. It is the counterpart of the function
 * CameraSensorHelper::gainCode.
 *
 * \return The real gain
 */
double CameraSensorHelper::gain(uint32_t gainCode) const
{
	const AnalogueGainConstants &k = gainConstants_;
	double gain = static_cast<double>(gainCode);

	switch (gainType_) {
	case AnalogueGainLinear:
		ASSERT(k.linear.m0 == 0 || k.linear.m1 == 0);

		return (k.linear.m0 * gain + k.linear.c0) /
		       (k.linear.m1 * gain + k.linear.c1);

	case AnalogueGainExponential:
		ASSERT(k.exp.a != 0 && k.exp.m != 0);

		return k.exp.a * std::exp2(k.exp.m * gain);

	default:
		ASSERT(false);
		return 0.0;
	}
}

/**
 * \enum CameraSensorHelper::AnalogueGainType
 * \brief The gain calculation modes as defined by the MIPI CCS
 *
 * Describes the image sensor analogue gain capabilities.
 * Two modes are possible, depending on the sensor: Linear and Exponential.
 */

/**
 * \var CameraSensorHelper::AnalogueGainLinear
 * \brief Gain is computed using linear gain estimation
 *
 * The relationship between the integer gain parameter and the resulting gain
 * multiplier is given by the following equation:
 *
 * \f$gain=\frac{m0x+c0}{m1x+c1}\f$
 *
 * Where 'x' is the gain control parameter, and m0, m1, c0 and c1 are
 * image-sensor-specific constants of the sensor.
 * These constants are static parameters, and for any given image sensor either
 * m0 or m1 shall be zero.
 *
 * The full Gain equation therefore reduces to either:
 *
 * \f$gain=\frac{c0}{m1x+c1}\f$ or \f$\frac{m0x+c0}{c1}\f$
 */

/**
 * \var CameraSensorHelper::AnalogueGainExponential
 * \brief Gain is expressed using an exponential model
 *
 * The relationship between the integer gain parameter and the resulting gain
 * multiplier is given by the following equation:
 *
 * \f$gain = a \cdot 2^{m \cdot x}\f$
 *
 * Where 'x' is the gain control parameter, and 'a' and 'm' are image
 * sensor-specific constants.
 *
 * This is a subset of the MIPI CCS exponential gain model with the linear
 * factor 'a' being a constant, but with the exponent being configurable
 * through the 'm' coefficient.
 *
 * When the gain is expressed in dB, 'a' is equal to 1 and 'm' to
 * \f$log_{2}{10^{\frac{1}{20}}}\f$.
 */

/**
 * \struct CameraSensorHelper::AnalogueGainLinearConstants
 * \brief Analogue gain constants for the linear gain model
 *
 * \var CameraSensorHelper::AnalogueGainLinearConstants::m0
 * \brief Constant used in the linear gain coding/decoding
 *
 * \note Either m0 or m1 shall be zero.
 *
 * \var CameraSensorHelper::AnalogueGainLinearConstants::c0
 * \brief Constant used in the linear gain coding/decoding
 *
 * \var CameraSensorHelper::AnalogueGainLinearConstants::m1
 * \brief Constant used in the linear gain coding/decoding
 *
 * \note Either m0 or m1 shall be zero.
 *
 * \var CameraSensorHelper::AnalogueGainLinearConstants::c1
 * \brief Constant used in the linear gain coding/decoding
 */

/**
 * \struct CameraSensorHelper::AnalogueGainExpConstants
 * \brief Analogue gain constants for the exponential gain model
 *
 * \var CameraSensorHelper::AnalogueGainExpConstants::a
 * \brief Constant used in the exponential gain coding/decoding
 *
 * \var CameraSensorHelper::AnalogueGainExpConstants::m
 * \brief Constant used in the exponential gain coding/decoding
 */

/**
 * \struct CameraSensorHelper::AnalogueGainConstants
 * \brief Analogue gain model constants
 *
 * This union stores the constants used to calculate the analogue gain. The
 * CameraSensorHelper::gainType_ variable selects which union member is valid.
 *
 * \var CameraSensorHelper::AnalogueGainConstants::linear
 * \brief Constants for the linear gain model
 *
 * \var CameraSensorHelper::AnalogueGainConstants::exp
 * \brief Constants for the exponential gain model
 */

/**
 * \var CameraSensorHelper::blackLevel_
 * \brief The black level of the sensor
 * \sa CameraSensorHelper::blackLevel()
 */

/**
 * \var CameraSensorHelper::gainType_
 * \brief The analogue gain model type
 */

/**
 * \var CameraSensorHelper::gainConstants_
 * \brief The analogue gain parameters used for calculation
 *
 * The analogue gain is calculated through a formula, and its parameters are
 * sensor specific. Use this variable to store the values at init time.
 */

/**
 * \class CameraSensorHelperFactoryBase
 * \brief Base class for camera sensor helper factories
 *
 * The CameraSensorHelperFactoryBase class is the base of all specializations of
 * the CameraSensorHelperFactory class template. It implements the factory
 * registration, maintains a registry of factories, and provides access to the
 * registered factories.
 */

/**
 * \brief Construct a camera sensor helper factory base
 * \param[in] name Name of the camera sensor helper class
 *
 * Creating an instance of the factory base registers it with the global list of
 * factories, accessible through the factories() function.
 *
 * The factory \a name is used to look up factories and shall be unique.
 */
CameraSensorHelperFactoryBase::CameraSensorHelperFactoryBase(const std::string name)
	: name_(name)
{
	registerType(this);
}

/**
 * \brief Create an instance of the CameraSensorHelper corresponding to
 * a named factory
 * \param[in] name Name of the factory
 *
 * \return A unique pointer to a new instance of the CameraSensorHelper subclass
 * corresponding to the named factory or a null pointer if no such factory
 * exists
 */
std::unique_ptr<CameraSensorHelper> CameraSensorHelperFactoryBase::create(const std::string &name)
{
	const std::vector<CameraSensorHelperFactoryBase *> &factories =
		CameraSensorHelperFactoryBase::factories();

	for (const CameraSensorHelperFactoryBase *factory : factories) {
		if (name != factory->name_)
			continue;

		return factory->createInstance();
	}

	return nullptr;
}

/**
 * \brief Add a camera sensor helper class to the registry
 * \param[in] factory Factory to use to construct the camera sensor helper
 *
 * The caller is responsible to guarantee the uniqueness of the camera sensor
 * helper name.
 */
void CameraSensorHelperFactoryBase::registerType(CameraSensorHelperFactoryBase *factory)
{
	std::vector<CameraSensorHelperFactoryBase *> &factories =
		CameraSensorHelperFactoryBase::factories();

	factories.push_back(factory);
}

/**
 * \brief Retrieve the list of all camera sensor helper factories
 * \return The list of camera sensor helper factories
 */
std::vector<CameraSensorHelperFactoryBase *> &CameraSensorHelperFactoryBase::factories()
{
	/*
	 * The static factories map is defined inside the function to ensure
	 * it gets initialized on first use, without any dependency on link
	 * order.
	 */
	static std::vector<CameraSensorHelperFactoryBase *> factories;
	return factories;
}

/**
 * \class CameraSensorHelperFactory
 * \brief Registration of CameraSensorHelperFactory classes and creation of instances
 * \tparam _Helper The camera sensor helper class type for this factory
 *
 * To facilitate discovery and instantiation of CameraSensorHelper classes, the
 * CameraSensorHelperFactory class implements auto-registration of camera sensor
 * helpers. Each CameraSensorHelper subclass shall register itself using the
 * REGISTER_CAMERA_SENSOR_HELPER() macro, which will create a corresponding
 * instance of a CameraSensorHelperFactory subclass and register it with the
 * static list of factories.
 */

/**
 * \fn CameraSensorHelperFactory::CameraSensorHelperFactory(const char *name)
 * \brief Construct a camera sensor helper factory
 * \param[in] name Name of the camera sensor helper class
 *
 * Creating an instance of the factory registers it with the global list of
 * factories, accessible through the CameraSensorHelperFactoryBase::factories()
 * function.
 *
 * The factory \a name is used to look up factories and shall be unique.
 */

/**
 * \fn CameraSensorHelperFactory::createInstance() const
 * \brief Create an instance of the CameraSensorHelper corresponding to the
 * factory
 *
 * \return A unique pointer to a newly constructed instance of the
 * CameraSensorHelper subclass corresponding to the factory
 */

/**
 * \def REGISTER_CAMERA_SENSOR_HELPER
 * \brief Register a camera sensor helper with the camera sensor helper factory
 * \param[in] name Sensor model name used to register the class
 * \param[in] helper Class name of CameraSensorHelper derived class to register
 *
 * Register a CameraSensorHelper subclass with the factory and make it available
 * to try and match sensors.
 */

/* -----------------------------------------------------------------------------
 * Sensor-specific subclasses
 */

#ifndef __DOXYGEN__

/*
 * Helper function to compute the m parameter of the exponential gain model
 * when the gain code is expressed in dB.
 */
static constexpr double expGainDb(double step)
{
	constexpr double log2_10 = 3.321928094887362;

	/*
	 * The gain code is expressed in step * dB (e.g. in 0.1 dB steps):
	 *
	 * G_code = G_dB/step = 20/step*log10(G_linear)
	 *
	 * Inverting the formula, we get
	 *
	 * G_linear = 10^(step/20*G_code) = 2^(log2(10)*step/20*G_code)
	 */
	return log2_10 * step / 20;
}

class CameraSensorHelperAr0144 : public CameraSensorHelper
{
public:
	CameraSensorHelperAr0144()
	{
		/* Power-on default value: 168 at 12bits. */
		blackLevel_ = 2688;
	}

	uint32_t gainCode(double gain) const override
	{
		/* The recommended minimum gain is 1.6842 to avoid artifacts. */
		gain = std::clamp(gain, 1.0 / (1.0 - 13.0 / 32.0), 18.45);

		/*
		 * The analogue gain is made of a coarse exponential gain in
		 * the range [2^0, 2^4] and a fine inversely linear gain in the
		 * range [1.0, 2.0[. There is an additional fixed 1.153125
		 * multiplier when the coarse gain reaches 2^2.
		 */

		if (gain > 4.0)
			gain /= 1.153125;

		unsigned int coarse = std::log2(gain);
		unsigned int fine = (1 - (1 << coarse) / gain) * 32;

		/* The fine gain rounding depends on the coarse gain. */
		if (coarse == 1 || coarse == 3)
			fine &= ~1;
		else if (coarse == 4)
			fine &= ~3;

		return (coarse << 4) | (fine & 0xf);
	}

	double gain(uint32_t gainCode) const override
	{
		unsigned int coarse = gainCode >> 4;
		unsigned int fine = gainCode & 0xf;
		unsigned int d1;
		double d2, m;

		switch (coarse) {
		default:
		case 0:
			d1 = 1;
			d2 = 32.0;
			m = 1.0;
			break;
		case 1:
			d1 = 2;
			d2 = 16.0;
			m = 1.0;
			break;
		case 2:
			d1 = 1;
			d2 = 32.0;
			m = 1.153125;
			break;
		case 3:
			d1 = 2;
			d2 = 16.0;
			m = 1.153125;
			break;
		case 4:
			d1 = 4;
			d2 = 8.0;
			m = 1.153125;
			break;
		}

		/*
		 * With infinite precision, the calculated gain would be exact,
		 * and the reverse conversion with gainCode() would produce the
		 * same gain code. In the real world, rounding errors may cause
		 * the calculated gain to be lower by an amount negligible for
		 * all purposes, except for the reverse conversion. Converting
		 * the gain to a gain code could then return the quantized value
		 * just lower than the original gain code. To avoid this, tests
		 * showed that adding the machine epsilon to the multiplier m is
		 * sufficient.
		 */
		m += std::numeric_limits<decltype(m)>::epsilon();

		return m * (1 << coarse) / (1.0 - (fine / d1) / d2);
	}

private:
	static constexpr double kStep_ = 16;
};
REGISTER_CAMERA_SENSOR_HELPER("ar0144", CameraSensorHelperAr0144)

class CameraSensorHelperAr0521 : public CameraSensorHelper
{
public:
	uint32_t gainCode(double gain) const override
	{
		gain = std::clamp(gain, 1.0, 15.5);
		unsigned int coarse = std::log2(gain);
		unsigned int fine = (gain / (1 << coarse) - 1) * kStep_;

		return (coarse << 4) | (fine & 0xf);
	}

	double gain(uint32_t gainCode) const override
	{
		unsigned int coarse = gainCode >> 4;
		unsigned int fine = gainCode & 0xf;

		return (1 << coarse) * (1 + fine / kStep_);
	}

private:
	static constexpr double kStep_ = 16;
};
REGISTER_CAMERA_SENSOR_HELPER("ar0521", CameraSensorHelperAr0521)

class CameraSensorHelperImx214 : public CameraSensorHelper
{
public:
	CameraSensorHelperImx214()
	{
		/* From datasheet: 64 at 10bits. */
		blackLevel_ = 4096;
		gainType_ = AnalogueGainLinear;
		gainConstants_.linear = { 0, 512, -1, 512 };
	}
};
REGISTER_CAMERA_SENSOR_HELPER("imx214", CameraSensorHelperImx214)

class CameraSensorHelperImx219 : public CameraSensorHelper
{
public:
	CameraSensorHelperImx219()
	{
		/* From datasheet: 64 at 10bits. */
		blackLevel_ = 4096;
		gainType_ = AnalogueGainLinear;
		gainConstants_.linear = { 0, 256, -1, 256 };
	}
};
REGISTER_CAMERA_SENSOR_HELPER("imx219", CameraSensorHelperImx219)

class CameraSensorHelperImx258 : public CameraSensorHelper
{
public:
	CameraSensorHelperImx258()
	{
		/* From datasheet: 0x40 at 10bits. */
		blackLevel_ = 4096;
		gainType_ = AnalogueGainLinear;
		gainConstants_.linear = { 0, 512, -1, 512 };
	}
};
REGISTER_CAMERA_SENSOR_HELPER("imx258", CameraSensorHelperImx258)

class CameraSensorHelperImx283 : public CameraSensorHelper
{
public:
	CameraSensorHelperImx283()
	{
		/* From datasheet: 0x32 at 10bits. */
		blackLevel_ = 3200;
		gainType_ = AnalogueGainLinear;
		gainConstants_.linear = { 0, 2048, -1, 2048 };
	}
};
REGISTER_CAMERA_SENSOR_HELPER("imx283", CameraSensorHelperImx283)

class CameraSensorHelperImx290 : public CameraSensorHelper
{
public:
	CameraSensorHelperImx290()
	{
		gainType_ = AnalogueGainExponential;
		gainConstants_.exp = { 1.0, expGainDb(0.3) };
	}
};
REGISTER_CAMERA_SENSOR_HELPER("imx290", CameraSensorHelperImx290)

class CameraSensorHelperImx296 : public CameraSensorHelper
{
public:
	CameraSensorHelperImx296()
	{
		gainType_ = AnalogueGainExponential;
		gainConstants_.exp = { 1.0, expGainDb(0.1) };
	}
};
REGISTER_CAMERA_SENSOR_HELPER("imx296", CameraSensorHelperImx296)

class CameraSensorHelperImx327 : public CameraSensorHelperImx290
{
};
REGISTER_CAMERA_SENSOR_HELPER("imx327", CameraSensorHelperImx327)

class CameraSensorHelperImx335 : public CameraSensorHelper
{
public:
	CameraSensorHelperImx335()
	{
		/* From datasheet: 0x32 at 10bits. */
		blackLevel_ = 3200;
		gainType_ = AnalogueGainExponential;
		gainConstants_.exp = { 1.0, expGainDb(0.3) };
	}
};
REGISTER_CAMERA_SENSOR_HELPER("imx335", CameraSensorHelperImx335)

class CameraSensorHelperImx415 : public CameraSensorHelper
{
public:
	CameraSensorHelperImx415()
	{
		gainType_ = AnalogueGainExponential;
		gainConstants_.exp = { 1.0, expGainDb(0.3) };
	}
};
REGISTER_CAMERA_SENSOR_HELPER("imx415", CameraSensorHelperImx415)

class CameraSensorHelperImx477 : public CameraSensorHelper
{
public:
	CameraSensorHelperImx477()
	{