libcamera
v0.3.0+156644986c2
Supporting cameras in Linux since 2019

Base class for computing sensor tuning parameters using sensorspecific constants. More...
Classes  
struct  AnalogueGainConstants 
Analogue gain model constants. More...  
struct  AnalogueGainExpConstants 
Analogue gain constants for the exponential gain model. More...  
struct  AnalogueGainLinearConstants 
Analogue gain constants for the linear gain model. More...  
Public Member Functions  
std::optional< int16_t >  blackLevel () const 
Construct a CameraSensorHelper instance. More...  
virtual uint32_t  gainCode (double gain) const 
Compute gain code from the analogue gain absolute value. More...  
virtual double  gain (uint32_t gainCode) const 
Compute the real gain from the V4L2 subdev control gain code. More...  
Protected Types  
enum  AnalogueGainType { AnalogueGainLinear, AnalogueGainExponential } 
The gain calculation modes as defined by the MIPI CCS. More...  
Protected Attributes  
std::optional< int16_t >  blackLevel_ 
The black level of the sensor.  
AnalogueGainType  gainType_ 
The analogue gain model type.  
AnalogueGainConstants  gainConstants_ 
The analogue gain parameters used for calculation. More...  
Base class for computing sensor tuning parameters using sensorspecific constants.
Instances derived from CameraSensorHelper class are sensorspecific. Each supported sensor will have an associated base class defined.

protected 
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.

inline 
Construct a CameraSensorHelper instance.
CameraSensorHelper derived class instances shall never be constructed manually but always through the CameraSensorHelperFactoryBase::create() function.
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.
Black levels are typically the result of the following phenomena:
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.

virtual 
Compute the real gain from the V4L2 subdev control gain code.
[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.

virtual 
Compute gain code from the analogue gain absolute value.
[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.

protected 
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.