NekoCWD/libcamera
NekoCWD/libcamera
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages 7 Wiki Activity Actions

libcamera: libipa: camera_sensor_helper: Use variant instead of union

Browse source 
Use an `std::variant` to store the analogue gain instead of a bare union + tag.

Signed-off-by: Barnabás Pőcze <pobrn@protonmail.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
This commit is contained in:
Barnabás Pőcze 2024-12-09 10:04:17 +00:00
parent 3930b94021
commit 65dd707f74
2 changed files with 66 additions and 146 deletions
Download patch file Download diff file Expand all files Collapse all files

194
src/ipa/libipa/camera_sensor_helper.cpp
View file

@ -87,21 +87,16 @@ namespace ipa {
*/ */
uint32_t CameraSensorHelper::gainCode(double gain) const uint32_t CameraSensorHelper::gainCode(double gain) const
{ {
const AnalogueGainConstants &k = gainConstants_; if (auto *l = std::get_if<AnalogueGainLinear>(&gain_)) {
ASSERT(l->m0 == 0 || l->m1 == 0);
switch (gainType_) { return (l->c0 - l->c1 * gain) /
case AnalogueGainLinear: (l->m1 * gain - l->m0);
ASSERT(k.linear.m0 == 0 || k.linear.m1 == 0); } else if (auto *e = std::get_if<AnalogueGainExp>(&gain_)) {
ASSERT(e->a != 0 && e->m != 0);
return (k.linear.c0 - k.linear.c1 * gain) / return std::log2(gain / e->a) / e->m;
(k.linear.m1 * gain - k.linear.m0); } else {
case AnalogueGainExponential:
ASSERT(k.exp.a != 0 && k.exp.m != 0);
return std::log2(gain / k.exp.a) / k.exp.m;
default:
ASSERT(false); ASSERT(false);
return 0; return 0;
} }
@ -119,38 +114,26 @@ uint32_t CameraSensorHelper::gainCode(double gain) const
*/ */
double CameraSensorHelper::gain(uint32_t gainCode) const double CameraSensorHelper::gain(uint32_t gainCode) const
{ {
const AnalogueGainConstants &k = gainConstants_;
double gain = static_cast<double>(gainCode); double gain = static_cast<double>(gainCode);
switch (gainType_) { if (auto *l = std::get_if<AnalogueGainLinear>(&gain_)) {
case AnalogueGainLinear: ASSERT(l->m0 == 0 || l->m1 == 0);
ASSERT(k.linear.m0 == 0 || k.linear.m1 == 0);
return (k.linear.m0 * gain + k.linear.c0) / return (l->m0 * gain + l->c0) /
(k.linear.m1 * gain + k.linear.c1); (l->m1 * gain + l->c1);
} else if (auto *e = std::get_if<AnalogueGainExp>(&gain_)) {
ASSERT(e->a != 0 && e->m != 0);
case AnalogueGainExponential: return e->a * std::exp2(e->m * gain);
ASSERT(k.exp.a != 0 && k.exp.m != 0); } else {
return k.exp.a * std::exp2(k.exp.m * gain);
default:
ASSERT(false); ASSERT(false);
return 0.0; return 0.0;
} }
} }
/** /**
* \enum CameraSensorHelper::AnalogueGainType * \struct CameraSensorHelper::AnalogueGainLinear
* \brief The gain calculation modes as defined by the MIPI CCS * \brief Analogue gain constants for the linear gain model
*
* 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 * The relationship between the integer gain parameter and the resulting gain
* multiplier is given by the following equation: * multiplier is given by the following equation:
@ -165,11 +148,27 @@ double CameraSensorHelper::gain(uint32_t gainCode) const
* The full Gain equation therefore reduces to either: * The full Gain equation therefore reduces to either:
* *
* \f$gain=\frac{c0}{m1x+c1}\f$ or \f$\frac{m0x+c0}{c1}\f$ * \f$gain=\frac{c0}{m1x+c1}\f$ or \f$\frac{m0x+c0}{c1}\f$
*
* \var CameraSensorHelper::AnalogueGainLinear::m0
* \brief Constant used in the linear gain coding/decoding
*
* \note Either m0 or m1 shall be zero.
*
* \var CameraSensorHelper::AnalogueGainLinear::c0
* \brief Constant used in the linear gain coding/decoding
*
* \var CameraSensorHelper::AnalogueGainLinear::m1
* \brief Constant used in the linear gain coding/decoding
*
* \note Either m0 or m1 shall be zero.
*
* \var CameraSensorHelper::AnalogueGainLinear::c1
* \brief Constant used in the linear gain coding/decoding
*/ */
/** /**
* \var CameraSensorHelper::AnalogueGainExponential * \struct CameraSensorHelper::AnalogueGainExp
* \brief Gain is expressed using an exponential model * \brief Analogue gain constants for the exponential gain model
* *
* The relationship between the integer gain parameter and the resulting gain * The relationship between the integer gain parameter and the resulting gain
* multiplier is given by the following equation: * multiplier is given by the following equation:
@ -185,54 +184,14 @@ double CameraSensorHelper::gain(uint32_t gainCode) const
* *
* When the gain is expressed in dB, 'a' is equal to 1 and 'm' to * When the gain is expressed in dB, 'a' is equal to 1 and 'm' to
* \f$log_{2}{10^{\frac{1}{20}}}\f$. * \f$log_{2}{10^{\frac{1}{20}}}\f$.
*/
/**
* \struct CameraSensorHelper::AnalogueGainLinearConstants
* \brief Analogue gain constants for the linear gain model
* *
* \var CameraSensorHelper::AnalogueGainLinearConstants::m0 * \var CameraSensorHelper::AnalogueGainExp::a
* \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 * \brief Constant used in the exponential gain coding/decoding
* *
* \var CameraSensorHelper::AnalogueGainExpConstants::m * \var CameraSensorHelper::AnalogueGainExp::m
* \brief Constant used in the exponential gain coding/decoding * \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_ * \var CameraSensorHelper::blackLevel_
* \brief The black level of the sensor * \brief The black level of the sensor
@ -240,12 +199,7 @@ double CameraSensorHelper::gain(uint32_t gainCode) const
*/ */
/** /**
* \var CameraSensorHelper::gainType_ * \var CameraSensorHelper::gain_
* \brief The analogue gain model type
*/
/**
* \var CameraSensorHelper::gainConstants_
* \brief The analogue gain parameters used for calculation * \brief The analogue gain parameters used for calculation
* *
* The analogue gain is calculated through a formula, and its parameters are * The analogue gain is calculated through a formula, and its parameters are
@ -526,8 +480,7 @@ public:
{ {
/* From datasheet: 64 at 10bits. */ /* From datasheet: 64 at 10bits. */
blackLevel_ = 4096; blackLevel_ = 4096;
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 100, 0, 0, 1024 };
gainConstants_.linear = { 100, 0, 0, 1024 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("gc05a2", CameraSensorHelperGc05a2) REGISTER_CAMERA_SENSOR_HELPER("gc05a2", CameraSensorHelperGc05a2)
@ -539,8 +492,7 @@ public:
{ {
/* From datasheet: 64 at 10bits. */ /* From datasheet: 64 at 10bits. */
blackLevel_ = 4096; blackLevel_ = 4096;
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 100, 0, 0, 1024 };
gainConstants_.linear = { 100, 0, 0, 1024 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("gc08a3", CameraSensorHelperGc08a3) REGISTER_CAMERA_SENSOR_HELPER("gc08a3", CameraSensorHelperGc08a3)
@ -552,8 +504,7 @@ public:
{ {
/* From datasheet: 64 at 10bits. */ /* From datasheet: 64 at 10bits. */
blackLevel_ = 4096; blackLevel_ = 4096;
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 0, 512, -1, 512 };
gainConstants_.linear = { 0, 512, -1, 512 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("imx214", CameraSensorHelperImx214) REGISTER_CAMERA_SENSOR_HELPER("imx214", CameraSensorHelperImx214)
@ -565,8 +516,7 @@ public:
{ {
/* From datasheet: 64 at 10bits. */ /* From datasheet: 64 at 10bits. */
blackLevel_ = 4096; blackLevel_ = 4096;
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 0, 256, -1, 256 };
gainConstants_.linear = { 0, 256, -1, 256 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("imx219", CameraSensorHelperImx219) REGISTER_CAMERA_SENSOR_HELPER("imx219", CameraSensorHelperImx219)
@ -578,8 +528,7 @@ public:
{ {
/* From datasheet: 0x40 at 10bits. */ /* From datasheet: 0x40 at 10bits. */
blackLevel_ = 4096; blackLevel_ = 4096;
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 0, 512, -1, 512 };
gainConstants_.linear = { 0, 512, -1, 512 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("imx258", CameraSensorHelperImx258) REGISTER_CAMERA_SENSOR_HELPER("imx258", CameraSensorHelperImx258)
@ -591,8 +540,7 @@ public:
{ {
/* From datasheet: 0x32 at 10bits. */ /* From datasheet: 0x32 at 10bits. */
blackLevel_ = 3200; blackLevel_ = 3200;
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 0, 2048, -1, 2048 };
gainConstants_.linear = { 0, 2048, -1, 2048 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("imx283", CameraSensorHelperImx283) REGISTER_CAMERA_SENSOR_HELPER("imx283", CameraSensorHelperImx283)
@ -604,8 +552,7 @@ public:
{ {
/* From datasheet: 0xf0 at 12bits. */ /* From datasheet: 0xf0 at 12bits. */
blackLevel_ = 3840; blackLevel_ = 3840;
gainType_ = AnalogueGainExponential; gain_ = AnalogueGainExp{ 1.0, expGainDb(0.3) };
gainConstants_.exp = { 1.0, expGainDb(0.3) };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("imx290", CameraSensorHelperImx290) REGISTER_CAMERA_SENSOR_HELPER("imx290", CameraSensorHelperImx290)
@ -615,8 +562,7 @@ class CameraSensorHelperImx296 : public CameraSensorHelper
public: public:
CameraSensorHelperImx296() CameraSensorHelperImx296()
{ {
gainType_ = AnalogueGainExponential; gain_ = AnalogueGainExp{ 1.0, expGainDb(0.1) };
gainConstants_.exp = { 1.0, expGainDb(0.1) };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("imx296", CameraSensorHelperImx296) REGISTER_CAMERA_SENSOR_HELPER("imx296", CameraSensorHelperImx296)
@ -633,8 +579,7 @@ public:
{ {
/* From datasheet: 0x32 at 10bits. */ /* From datasheet: 0x32 at 10bits. */
blackLevel_ = 3200; blackLevel_ = 3200;
gainType_ = AnalogueGainExponential; gain_ = AnalogueGainExp{ 1.0, expGainDb(0.3) };
gainConstants_.exp = { 1.0, expGainDb(0.3) };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("imx335", CameraSensorHelperImx335) REGISTER_CAMERA_SENSOR_HELPER("imx335", CameraSensorHelperImx335)
@ -644,8 +589,7 @@ class CameraSensorHelperImx415 : public CameraSensorHelper
public: public:
CameraSensorHelperImx415() CameraSensorHelperImx415()
{ {
gainType_ = AnalogueGainExponential; gain_ = AnalogueGainExp{ 1.0, expGainDb(0.3) };
gainConstants_.exp = { 1.0, expGainDb(0.3) };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("imx415", CameraSensorHelperImx415) REGISTER_CAMERA_SENSOR_HELPER("imx415", CameraSensorHelperImx415)
@ -660,8 +604,7 @@ class CameraSensorHelperImx477 : public CameraSensorHelper
public: public:
CameraSensorHelperImx477() CameraSensorHelperImx477()
{ {
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 0, 1024, -1, 1024 };
gainConstants_.linear = { 0, 1024, -1, 1024 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("imx477", CameraSensorHelperImx477) REGISTER_CAMERA_SENSOR_HELPER("imx477", CameraSensorHelperImx477)
@ -675,8 +618,7 @@ public:
* The Sensor Manual doesn't appear to document the gain model. * The Sensor Manual doesn't appear to document the gain model.
* This has been validated with some empirical testing only. * This has been validated with some empirical testing only.
*/ */
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 1, 0, 0, 128 };
gainConstants_.linear = { 1, 0, 0, 128 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("ov2685", CameraSensorHelperOv2685) REGISTER_CAMERA_SENSOR_HELPER("ov2685", CameraSensorHelperOv2685)
@ -686,8 +628,7 @@ class CameraSensorHelperOv2740 : public CameraSensorHelper
public: public:
CameraSensorHelperOv2740() CameraSensorHelperOv2740()
{ {
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 1, 0, 0, 128 };
gainConstants_.linear = { 1, 0, 0, 128 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("ov2740", CameraSensorHelperOv2740) REGISTER_CAMERA_SENSOR_HELPER("ov2740", CameraSensorHelperOv2740)
@ -699,8 +640,7 @@ public:
{ {
/* From datasheet: 0x40 at 12bits. */ /* From datasheet: 0x40 at 12bits. */
blackLevel_ = 1024; blackLevel_ = 1024;
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 1, 0, 0, 128 };
gainConstants_.linear = { 1, 0, 0, 128 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("ov4689", CameraSensorHelperOv4689) REGISTER_CAMERA_SENSOR_HELPER("ov4689", CameraSensorHelperOv4689)
@ -712,8 +652,7 @@ public:
{ {
/* From datasheet: 0x10 at 10bits. */ /* From datasheet: 0x10 at 10bits. */
blackLevel_ = 1024; blackLevel_ = 1024;
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 1, 0, 0, 16 };
gainConstants_.linear = { 1, 0, 0, 16 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("ov5640", CameraSensorHelperOv5640) REGISTER_CAMERA_SENSOR_HELPER("ov5640", CameraSensorHelperOv5640)
@ -723,8 +662,7 @@ class CameraSensorHelperOv5647 : public CameraSensorHelper
public: public:
CameraSensorHelperOv5647() CameraSensorHelperOv5647()
{ {
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 1, 0, 0, 16 };
gainConstants_.linear = { 1, 0, 0, 16 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("ov5647", CameraSensorHelperOv5647) REGISTER_CAMERA_SENSOR_HELPER("ov5647", CameraSensorHelperOv5647)
@ -734,8 +672,7 @@ class CameraSensorHelperOv5670 : public CameraSensorHelper
public: public:
CameraSensorHelperOv5670() CameraSensorHelperOv5670()
{ {
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 1, 0, 0, 128 };
gainConstants_.linear = { 1, 0, 0, 128 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("ov5670", CameraSensorHelperOv5670) REGISTER_CAMERA_SENSOR_HELPER("ov5670", CameraSensorHelperOv5670)
@ -747,8 +684,7 @@ public:
{ {
/* From Linux kernel driver: 0x40 at 10bits. */ /* From Linux kernel driver: 0x40 at 10bits. */
blackLevel_ = 4096; blackLevel_ = 4096;
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 1, 0, 0, 128 };
gainConstants_.linear = { 1, 0, 0, 128 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("ov5675", CameraSensorHelperOv5675) REGISTER_CAMERA_SENSOR_HELPER("ov5675", CameraSensorHelperOv5675)
@ -758,8 +694,7 @@ class CameraSensorHelperOv5693 : public CameraSensorHelper
public: public:
CameraSensorHelperOv5693() CameraSensorHelperOv5693()
{ {
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 1, 0, 0, 16 };
gainConstants_.linear = { 1, 0, 0, 16 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("ov5693", CameraSensorHelperOv5693) REGISTER_CAMERA_SENSOR_HELPER("ov5693", CameraSensorHelperOv5693)
@ -769,8 +704,7 @@ class CameraSensorHelperOv64a40 : public CameraSensorHelper
public: public:
CameraSensorHelperOv64a40() CameraSensorHelperOv64a40()
{ {
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 1, 0, 0, 128 };
gainConstants_.linear = { 1, 0, 0, 128 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("ov64a40", CameraSensorHelperOv64a40) REGISTER_CAMERA_SENSOR_HELPER("ov64a40", CameraSensorHelperOv64a40)
@ -780,15 +714,13 @@ class CameraSensorHelperOv8858 : public CameraSensorHelper
public: public:
CameraSensorHelperOv8858() CameraSensorHelperOv8858()
{ {
gainType_ = AnalogueGainLinear;
/* /*
* \todo Validate the selected 1/128 step value as it differs * \todo Validate the selected 1/128 step value as it differs
* from what the sensor manual describes. * from what the sensor manual describes.
* *
* See: https://patchwork.linuxtv.org/project/linux-media/patch/20221106171129.166892-2-nicholas@rothemail.net/#142267 * See: https://patchwork.linuxtv.org/project/linux-media/patch/20221106171129.166892-2-nicholas@rothemail.net/#142267
*/ */
gainConstants_.linear = { 1, 0, 0, 128 }; gain_ = AnalogueGainLinear{ 1, 0, 0, 128 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("ov8858", CameraSensorHelperOv8858) REGISTER_CAMERA_SENSOR_HELPER("ov8858", CameraSensorHelperOv8858)
@ -798,8 +730,7 @@ class CameraSensorHelperOv8865 : public CameraSensorHelper
public: public:
CameraSensorHelperOv8865() CameraSensorHelperOv8865()
{ {
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 1, 0, 0, 128 };
gainConstants_.linear = { 1, 0, 0, 128 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("ov8865", CameraSensorHelperOv8865) REGISTER_CAMERA_SENSOR_HELPER("ov8865", CameraSensorHelperOv8865)
@ -809,8 +740,7 @@ class CameraSensorHelperOv13858 : public CameraSensorHelper
public: public:
CameraSensorHelperOv13858() CameraSensorHelperOv13858()
{ {
gainType_ = AnalogueGainLinear; gain_ = AnalogueGainLinear{ 1, 0, 0, 128 };
gainConstants_.linear = { 1, 0, 0, 128 };
} }
}; };
REGISTER_CAMERA_SENSOR_HELPER("ov13858", CameraSensorHelperOv13858) REGISTER_CAMERA_SENSOR_HELPER("ov13858", CameraSensorHelperOv13858)

18
src/ipa/libipa/camera_sensor_helper.h
View file

@ -11,6 +11,7 @@
#include <optional> #include <optional>
#include <stdint.h> #include <stdint.h>
#include <string> #include <string>
#include <variant>
#include <vector> #include <vector>
#include <libcamera/base/class.h> #include <libcamera/base/class.h>
@ -30,31 +31,20 @@ public:
virtual double gain(uint32_t gainCode) const; virtual double gain(uint32_t gainCode) const;
protected: protected:
enum AnalogueGainType { struct AnalogueGainLinear {
AnalogueGainLinear,
AnalogueGainExponential,
};
struct AnalogueGainLinearConstants {
int16_t m0; int16_t m0;
int16_t c0; int16_t c0;
int16_t m1; int16_t m1;
int16_t c1; int16_t c1;
}; };
struct AnalogueGainExpConstants { struct AnalogueGainExp {
double a; double a;
double m; double m;
}; };
union AnalogueGainConstants {
AnalogueGainLinearConstants linear;
AnalogueGainExpConstants exp;
};
std::optional<int16_t> blackLevel_; std::optional<int16_t> blackLevel_;
AnalogueGainType gainType_; std::variant<std::monostate, AnalogueGainLinear, AnalogueGainExp> gain_;
AnalogueGainConstants gainConstants_;
private: private:
LIBCAMERA_DISABLE_COPY_AND_MOVE(CameraSensorHelper) LIBCAMERA_DISABLE_COPY_AND_MOVE(CameraSensorHelper)