Message ID | 20240913075750.35115-2-stefan.klug@ideasonboard.com |
---|---|
State | Superseded |
Headers | show |
Series |
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Related | show |
Quoting Stefan Klug (2024-09-13 08:57:19) > The MatrixInterpolator is great for interpolation of matrices for > different color temperatures. It has however one limitation - it can > only handle matrices. For LSC it would be great to interpolate the LSC > tables (or even polynomials) using the same approach. Add a generic > Interpolator class based on the existing MatrixInterpolator. This calss s/calss/class/ > can be adapted to any other type using partial template specialization. > > Signed-off-by: Stefan Klug <stefan.klug@ideasonboard.com> > --- > src/ipa/libipa/interpolator.cpp | 156 ++++++++++++++++++++++++++++++++ > src/ipa/libipa/interpolator.h | 131 +++++++++++++++++++++++++++ > src/ipa/libipa/meson.build | 2 + > 3 files changed, 289 insertions(+) > create mode 100644 src/ipa/libipa/interpolator.cpp > create mode 100644 src/ipa/libipa/interpolator.h > > diff --git a/src/ipa/libipa/interpolator.cpp b/src/ipa/libipa/interpolator.cpp > new file mode 100644 > index 000000000000..05a4af984f9a > --- /dev/null > +++ b/src/ipa/libipa/interpolator.cpp > @@ -0,0 +1,156 @@ > +/* SPDX-License-Identifier: LGPL-2.1-or-later */ > +/* > + * Copyright (C) 2024, Paul Elder <paul.elder@ideasonboard.com> > + * > + * Helper class for interpolating objects > + */ > +#include "interpolator.h" > + > +#include <algorithm> > +#include <string> > + > +#include <libcamera/base/log.h> > + > +#include "libcamera/internal/yaml_parser.h" > + > +#include "interpolator.h" > + > +/** > + * \file interpolator.h > + * \brief Helper class for linear interpolating a set of objects > + */ > + > +namespace libcamera { > + > +LOG_DEFINE_CATEGORY(Interpolator) > + > +namespace ipa { > + > +/** > + * \class Interpolator > + * \brief Class for storing, retrieving, and interpolating objects > + * \tparam T Type of objects stored in the interpolator > + * > + * The main use case is to pass a map from color temperatures to corresponding > + * objects (eg. matrices for color correction), and then requesting a > + * interpolated object for a specific color temperature. This class will > + * abstract away the interpolation portion. > + */ > + > +/** > + * \fn Interpolator::Interpolator() > + * \brief Construct a empty interpolator > + */ > + > +/** > + * \fn Interpolator::Interpolator(const std::map<unsigned int, T> &data) > + * \brief Construct a interpolator from a map of objects > + * \param data Map from which to construct the interpolator > + */ > + > +/** > + * \fn Interpolator::Interpolator(std::map<unsigned int, T> &&data) > + * \brief Construct a interpolator from a map of objects s/a interpolator/an interpolator/ > + * \param data Map from which to construct the interpolator > + */ > + > +/** > + * \fn int Interpolator<T>::readYaml(const libcamera::YamlObject &yaml, > + const std::string &key_name, > + const std::string &value_name) > + * \brief Initialize an Interpolator instance from yaml > + * \tparam T Type of data stored in the interpolator > + * \param[in] yaml The yaml object that contains the map of unsigned integers to objects > + * \param[in] key_name The name of the key in the yaml object > + * \param[in] value_name The name of the value in the yaml object > + * > + * The yaml object is expected to be a list of maps. Each map has two or more > + * pairs: one of \a key_name to the key value (usually color temperature), and > + * one or more of \a value_name to the object. This is a bit difficult to > + * explain, so here is an example (in python, as it is easier to parse than > + * yaml): > + * [ > + * { > + * 'ct': 2860, > + * 'ccm': [ 2.12089, -0.52461, -0.59629, > + * -0.85342, 2.80445, -0.95103, > + * -0.26897, -1.14788, 2.41685 ], > + * 'offsets': [ 0, 0, 0 ] > + * }, > + * > + * { > + * 'ct': 2960, > + * 'ccm': [ 2.26962, -0.54174, -0.72789, > + * -0.77008, 2.60271, -0.83262, > + * -0.26036, -1.51254, 2.77289 ], > + * 'offsets': [ 0, 0, 0 ] > + * }, > + * > + * { > + * 'ct': 3603, > + * 'ccm': [ 2.18644, -0.66148, -0.52496, > + * -0.77828, 2.69474, -0.91645, > + * -0.25239, -0.83059, 2.08298 ], > + * 'offsets': [ 0, 0, 0 ] > + * }, > + * ] > + * > + * In this case, \a key_name would be 'ct', and \a value_name can be either > + * 'ccm' or 'offsets'. This way multiple interpolators can be defined in > + * one set of color temperature ranges in the tuning file, and they can be > + * retrieved separately with the \a value_name parameter. > + * > + * \return Zero on success, negative error code otherwise > + */ > + > +/** > + * \fn void Interpolator<T>::setQuantization(const unsigned int q) > + * \brief Set the quantization value > + * \param[in] q The quantization value > + * > + * Sets the quantization value. When this is set, 'key' gets quantized to this > + * size, before doing the interpolation. This can help in reducing the number of > + * updated pushed to the hardware. s/updated/updates/ And that's all I can find so ... Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> > + * > + * Note that normally a threshold needs to be combined with quantization. > + * Otherwise a value that swings around the edge of the quantization step will > + * lead to constant updates. > + */ > + > +/** > + * \fn void Interpolator<T>::setData(std::map<unsigned int, T> &&data) > + * \brief Set the internal map > + * > + * Overwrites the internal map using move semantics. > + */ > + > +/** > + * \fn const T& Interpolator<T>::getInterpolated(unsigned int key, unsigned int *quantizedKey = nullptr) > + * \brief Retrieve a a interpolated value for the given key > + * \param[in] key The unsigned integer key of the object to retrieve > + * \param[out] quantizedKey If provided, the key value after quantization > + * \return The object corresponding to the key. The object is cached internally, > + * so on successive calls with the same key (after quantization) interpolation > + * is not recalculated. > + */ > + > +/** > + * \fn void Interpolator<T>::interpolate(const T &a, const T &b, T &dest, double > + * lambda) > + * \brief Interpolate between two instances of T > + * \param a The first value to interpolate > + * \param b The second value to interpolate > + * \param dest The destination for the interpolated value > + * \param lambda The interpolation factor (0..1) > + * > + * Interpolates between a and b according to lambda. It calculates dest = a * > + * (1.0 - lambda) + b * lambda; > + * > + * If T supports multiplication with double and addition, this function can be > + * used as is. For other types this function can be overwritten using partial > + * template specialization. > + */ > + > +} /* namespace ipa */ > + > +} /* namespace libcamera */ > diff --git a/src/ipa/libipa/interpolator.h b/src/ipa/libipa/interpolator.h > new file mode 100644 > index 000000000000..fffce21465fe > --- /dev/null > +++ b/src/ipa/libipa/interpolator.h > @@ -0,0 +1,131 @@ > +/* SPDX-License-Identifier: LGPL-2.1-or-later */ > +/* > + * Copyright (C) 2024, Paul Elder <paul.elder@ideasonboard.com> > + * > + * Helper class for interpolating maps of objects > + */ > + > +#pragma once > + > +#include <algorithm> > +#include <cmath> > +#include <map> > +#include <string> > +#include <tuple> > + > +#include <libcamera/base/log.h> > + > +#include "libcamera/internal/yaml_parser.h" > + > +namespace libcamera { > + > +LOG_DECLARE_CATEGORY(Interpolator) > + > +namespace ipa { > + > +template<typename T> > +class Interpolator > +{ > +public: > + Interpolator() = default; > + Interpolator(const std::map<unsigned int, T> &data) > + : data_(data) > + { > + } > + Interpolator(std::map<unsigned int, T> &&data) > + : data_(std::move(data)) > + { > + } > + > + ~Interpolator() = default; > + > + int readYaml(const libcamera::YamlObject &yaml, > + const std::string &key_name, > + const std::string &value_name) > + { > + data_.clear(); > + lastInterpolatedKey_.reset(); > + > + if (!yaml.isList()) { > + LOG(Interpolator, Error) << "yaml object must be a list"; > + return -EINVAL; > + } > + > + for (const auto &value : yaml.asList()) { > + unsigned int ct = std::stoul(value[key_name].get<std::string>("")); > + std::optional<T> data = > + value[value_name].get<T>(); > + if (!data) { > + return -EINVAL; > + } > + > + data_[ct] = *data; > + } > + > + if (data_.size() < 1) { > + LOG(Interpolator, Error) << "Need at least one element"; > + return -EINVAL; > + } > + > + return 0; > + } > + > + void setQuantization(const unsigned int q) > + { > + quantization_ = q; > + } > + > + void setData(std::map<unsigned int, T> &&data) > + { > + data_ = std::move(data); > + lastInterpolatedKey_.reset(); > + } > + > + const T &getInterpolated(unsigned int key, unsigned int *quantizedKey = nullptr) > + { > + ASSERT(data_.size() > 0); > + > + if (quantization_ > 0) > + key = std::lround(key / static_cast<double>(quantization_)) * quantization_; > + > + if (quantizedKey) > + *quantizedKey = key; > + > + if (lastInterpolatedKey_.has_value() && > + *lastInterpolatedKey_ == key) > + return lastInterpolatedValue_; > + > + auto it = data_.lower_bound(key); > + > + if (it == data_.begin()) > + return it->second; > + > + if (it == data_.end()) > + return std::prev(it)->second; > + > + if (it->first == key) > + return it->second; > + > + auto it2 = std::prev(it); > + double lambda = (key - it2->first) / static_cast<double>(it->first - it2->first); > + interpolate(it2->second, it->second, lastInterpolatedValue_, lambda); > + lastInterpolatedKey_ = key; > + > + return lastInterpolatedValue_; > + } > + > + void interpolate(const T &a, const T &b, T &dest, double lambda) > + { > + dest = a * (1.0 - lambda) + b * lambda; > + } > + > +private: > + std::map<unsigned int, T> data_; > + T lastInterpolatedValue_; > + std::optional<unsigned int> lastInterpolatedKey_; > + unsigned int quantization_ = 0; > +}; > + > +} /* namespace ipa */ > + > +} /* namespace libcamera */ > diff --git a/src/ipa/libipa/meson.build b/src/ipa/libipa/meson.build > index eff8ce2660f1..2c2712a7d252 100644 > --- a/src/ipa/libipa/meson.build > +++ b/src/ipa/libipa/meson.build > @@ -7,6 +7,7 @@ libipa_headers = files([ > 'exposure_mode_helper.h', > 'fc_queue.h', > 'histogram.h', > + 'interpolator.h', > 'matrix.h', > 'matrix_interpolator.h', > 'module.h', > @@ -21,6 +22,7 @@ libipa_sources = files([ > 'exposure_mode_helper.cpp', > 'fc_queue.cpp', > 'histogram.cpp', > + 'interpolator.cpp', > 'matrix.cpp', > 'matrix_interpolator.cpp', > 'module.cpp', > -- > 2.43.0 >
On Fri, Sep 13, 2024 at 09:57:19AM +0200, Stefan Klug wrote: > The MatrixInterpolator is great for interpolation of matrices for > different color temperatures. It has however one limitation - it can > only handle matrices. For LSC it would be great to interpolate the LSC > tables (or even polynomials) using the same approach. Add a generic > Interpolator class based on the existing MatrixInterpolator. This calss > can be adapted to any other type using partial template specialization. > > Signed-off-by: Stefan Klug <stefan.klug@ideasonboard.com> Kieran beat me to it but "an interpolator". Other than that, Reviewed-by: Paul Elder <paul.elder@ideasonboard.com> > --- > src/ipa/libipa/interpolator.cpp | 156 ++++++++++++++++++++++++++++++++ > src/ipa/libipa/interpolator.h | 131 +++++++++++++++++++++++++++ > src/ipa/libipa/meson.build | 2 + > 3 files changed, 289 insertions(+) > create mode 100644 src/ipa/libipa/interpolator.cpp > create mode 100644 src/ipa/libipa/interpolator.h > > diff --git a/src/ipa/libipa/interpolator.cpp b/src/ipa/libipa/interpolator.cpp > new file mode 100644 > index 000000000000..05a4af984f9a > --- /dev/null > +++ b/src/ipa/libipa/interpolator.cpp > @@ -0,0 +1,156 @@ > +/* SPDX-License-Identifier: LGPL-2.1-or-later */ > +/* > + * Copyright (C) 2024, Paul Elder <paul.elder@ideasonboard.com> > + * > + * Helper class for interpolating objects > + */ > +#include "interpolator.h" > + > +#include <algorithm> > +#include <string> > + > +#include <libcamera/base/log.h> > + > +#include "libcamera/internal/yaml_parser.h" > + > +#include "interpolator.h" > + > +/** > + * \file interpolator.h > + * \brief Helper class for linear interpolating a set of objects > + */ > + > +namespace libcamera { > + > +LOG_DEFINE_CATEGORY(Interpolator) > + > +namespace ipa { > + > +/** > + * \class Interpolator > + * \brief Class for storing, retrieving, and interpolating objects > + * \tparam T Type of objects stored in the interpolator > + * > + * The main use case is to pass a map from color temperatures to corresponding > + * objects (eg. matrices for color correction), and then requesting a > + * interpolated object for a specific color temperature. This class will > + * abstract away the interpolation portion. > + */ > + > +/** > + * \fn Interpolator::Interpolator() > + * \brief Construct a empty interpolator > + */ > + > +/** > + * \fn Interpolator::Interpolator(const std::map<unsigned int, T> &data) > + * \brief Construct a interpolator from a map of objects > + * \param data Map from which to construct the interpolator > + */ > + > +/** > + * \fn Interpolator::Interpolator(std::map<unsigned int, T> &&data) > + * \brief Construct a interpolator from a map of objects > + * \param data Map from which to construct the interpolator > + */ > + > +/** > + * \fn int Interpolator<T>::readYaml(const libcamera::YamlObject &yaml, > + const std::string &key_name, > + const std::string &value_name) > + * \brief Initialize an Interpolator instance from yaml > + * \tparam T Type of data stored in the interpolator > + * \param[in] yaml The yaml object that contains the map of unsigned integers to objects > + * \param[in] key_name The name of the key in the yaml object > + * \param[in] value_name The name of the value in the yaml object > + * > + * The yaml object is expected to be a list of maps. Each map has two or more > + * pairs: one of \a key_name to the key value (usually color temperature), and > + * one or more of \a value_name to the object. This is a bit difficult to > + * explain, so here is an example (in python, as it is easier to parse than > + * yaml): > + * [ > + * { > + * 'ct': 2860, > + * 'ccm': [ 2.12089, -0.52461, -0.59629, > + * -0.85342, 2.80445, -0.95103, > + * -0.26897, -1.14788, 2.41685 ], > + * 'offsets': [ 0, 0, 0 ] > + * }, > + * > + * { > + * 'ct': 2960, > + * 'ccm': [ 2.26962, -0.54174, -0.72789, > + * -0.77008, 2.60271, -0.83262, > + * -0.26036, -1.51254, 2.77289 ], > + * 'offsets': [ 0, 0, 0 ] > + * }, > + * > + * { > + * 'ct': 3603, > + * 'ccm': [ 2.18644, -0.66148, -0.52496, > + * -0.77828, 2.69474, -0.91645, > + * -0.25239, -0.83059, 2.08298 ], > + * 'offsets': [ 0, 0, 0 ] > + * }, > + * ] > + * > + * In this case, \a key_name would be 'ct', and \a value_name can be either > + * 'ccm' or 'offsets'. This way multiple interpolators can be defined in > + * one set of color temperature ranges in the tuning file, and they can be > + * retrieved separately with the \a value_name parameter. > + * > + * \return Zero on success, negative error code otherwise > + */ > + > +/** > + * \fn void Interpolator<T>::setQuantization(const unsigned int q) > + * \brief Set the quantization value > + * \param[in] q The quantization value > + * > + * Sets the quantization value. When this is set, 'key' gets quantized to this > + * size, before doing the interpolation. This can help in reducing the number of > + * updated pushed to the hardware. > + * > + * Note that normally a threshold needs to be combined with quantization. > + * Otherwise a value that swings around the edge of the quantization step will > + * lead to constant updates. > + */ > + > +/** > + * \fn void Interpolator<T>::setData(std::map<unsigned int, T> &&data) > + * \brief Set the internal map > + * > + * Overwrites the internal map using move semantics. > + */ > + > +/** > + * \fn const T& Interpolator<T>::getInterpolated(unsigned int key, unsigned int *quantizedKey = nullptr) > + * \brief Retrieve a a interpolated value for the given key > + * \param[in] key The unsigned integer key of the object to retrieve > + * \param[out] quantizedKey If provided, the key value after quantization > + * \return The object corresponding to the key. The object is cached internally, > + * so on successive calls with the same key (after quantization) interpolation > + * is not recalculated. > + */ > + > +/** > + * \fn void Interpolator<T>::interpolate(const T &a, const T &b, T &dest, double > + * lambda) > + * \brief Interpolate between two instances of T > + * \param a The first value to interpolate > + * \param b The second value to interpolate > + * \param dest The destination for the interpolated value > + * \param lambda The interpolation factor (0..1) > + * > + * Interpolates between a and b according to lambda. It calculates dest = a * > + * (1.0 - lambda) + b * lambda; > + * > + * If T supports multiplication with double and addition, this function can be > + * used as is. For other types this function can be overwritten using partial > + * template specialization. > + */ > + > +} /* namespace ipa */ > + > +} /* namespace libcamera */ > diff --git a/src/ipa/libipa/interpolator.h b/src/ipa/libipa/interpolator.h > new file mode 100644 > index 000000000000..fffce21465fe > --- /dev/null > +++ b/src/ipa/libipa/interpolator.h > @@ -0,0 +1,131 @@ > +/* SPDX-License-Identifier: LGPL-2.1-or-later */ > +/* > + * Copyright (C) 2024, Paul Elder <paul.elder@ideasonboard.com> > + * > + * Helper class for interpolating maps of objects > + */ > + > +#pragma once > + > +#include <algorithm> > +#include <cmath> > +#include <map> > +#include <string> > +#include <tuple> > + > +#include <libcamera/base/log.h> > + > +#include "libcamera/internal/yaml_parser.h" > + > +namespace libcamera { > + > +LOG_DECLARE_CATEGORY(Interpolator) > + > +namespace ipa { > + > +template<typename T> > +class Interpolator > +{ > +public: > + Interpolator() = default; > + Interpolator(const std::map<unsigned int, T> &data) > + : data_(data) > + { > + } > + Interpolator(std::map<unsigned int, T> &&data) > + : data_(std::move(data)) > + { > + } > + > + ~Interpolator() = default; > + > + int readYaml(const libcamera::YamlObject &yaml, > + const std::string &key_name, > + const std::string &value_name) > + { > + data_.clear(); > + lastInterpolatedKey_.reset(); > + > + if (!yaml.isList()) { > + LOG(Interpolator, Error) << "yaml object must be a list"; > + return -EINVAL; > + } > + > + for (const auto &value : yaml.asList()) { > + unsigned int ct = std::stoul(value[key_name].get<std::string>("")); > + std::optional<T> data = > + value[value_name].get<T>(); > + if (!data) { > + return -EINVAL; > + } > + > + data_[ct] = *data; > + } > + > + if (data_.size() < 1) { > + LOG(Interpolator, Error) << "Need at least one element"; > + return -EINVAL; > + } > + > + return 0; > + } > + > + void setQuantization(const unsigned int q) > + { > + quantization_ = q; > + } > + > + void setData(std::map<unsigned int, T> &&data) > + { > + data_ = std::move(data); > + lastInterpolatedKey_.reset(); > + } > + > + const T &getInterpolated(unsigned int key, unsigned int *quantizedKey = nullptr) > + { > + ASSERT(data_.size() > 0); > + > + if (quantization_ > 0) > + key = std::lround(key / static_cast<double>(quantization_)) * quantization_; > + > + if (quantizedKey) > + *quantizedKey = key; > + > + if (lastInterpolatedKey_.has_value() && > + *lastInterpolatedKey_ == key) > + return lastInterpolatedValue_; > + > + auto it = data_.lower_bound(key); > + > + if (it == data_.begin()) > + return it->second; > + > + if (it == data_.end()) > + return std::prev(it)->second; > + > + if (it->first == key) > + return it->second; > + > + auto it2 = std::prev(it); > + double lambda = (key - it2->first) / static_cast<double>(it->first - it2->first); > + interpolate(it2->second, it->second, lastInterpolatedValue_, lambda); > + lastInterpolatedKey_ = key; > + > + return lastInterpolatedValue_; > + } > + > + void interpolate(const T &a, const T &b, T &dest, double lambda) > + { > + dest = a * (1.0 - lambda) + b * lambda; > + } > + > +private: > + std::map<unsigned int, T> data_; > + T lastInterpolatedValue_; > + std::optional<unsigned int> lastInterpolatedKey_; > + unsigned int quantization_ = 0; > +}; > + > +} /* namespace ipa */ > + > +} /* namespace libcamera */ > diff --git a/src/ipa/libipa/meson.build b/src/ipa/libipa/meson.build > index eff8ce2660f1..2c2712a7d252 100644 > --- a/src/ipa/libipa/meson.build > +++ b/src/ipa/libipa/meson.build > @@ -7,6 +7,7 @@ libipa_headers = files([ > 'exposure_mode_helper.h', > 'fc_queue.h', > 'histogram.h', > + 'interpolator.h', > 'matrix.h', > 'matrix_interpolator.h', > 'module.h', > @@ -21,6 +22,7 @@ libipa_sources = files([ > 'exposure_mode_helper.cpp', > 'fc_queue.cpp', > 'histogram.cpp', > + 'interpolator.cpp', > 'matrix.cpp', > 'matrix_interpolator.cpp', > 'module.cpp', > -- > 2.43.0 >
diff --git a/src/ipa/libipa/interpolator.cpp b/src/ipa/libipa/interpolator.cpp new file mode 100644 index 000000000000..05a4af984f9a --- /dev/null +++ b/src/ipa/libipa/interpolator.cpp @@ -0,0 +1,156 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +/* + * Copyright (C) 2024, Paul Elder <paul.elder@ideasonboard.com> + * + * Helper class for interpolating objects + */ +#include "interpolator.h" + +#include <algorithm> +#include <string> + +#include <libcamera/base/log.h> + +#include "libcamera/internal/yaml_parser.h" + +#include "interpolator.h" + +/** + * \file interpolator.h + * \brief Helper class for linear interpolating a set of objects + */ + +namespace libcamera { + +LOG_DEFINE_CATEGORY(Interpolator) + +namespace ipa { + +/** + * \class Interpolator + * \brief Class for storing, retrieving, and interpolating objects + * \tparam T Type of objects stored in the interpolator + * + * The main use case is to pass a map from color temperatures to corresponding + * objects (eg. matrices for color correction), and then requesting a + * interpolated object for a specific color temperature. This class will + * abstract away the interpolation portion. + */ + +/** + * \fn Interpolator::Interpolator() + * \brief Construct a empty interpolator + */ + +/** + * \fn Interpolator::Interpolator(const std::map<unsigned int, T> &data) + * \brief Construct a interpolator from a map of objects + * \param data Map from which to construct the interpolator + */ + +/** + * \fn Interpolator::Interpolator(std::map<unsigned int, T> &&data) + * \brief Construct a interpolator from a map of objects + * \param data Map from which to construct the interpolator + */ + +/** + * \fn int Interpolator<T>::readYaml(const libcamera::YamlObject &yaml, + const std::string &key_name, + const std::string &value_name) + * \brief Initialize an Interpolator instance from yaml + * \tparam T Type of data stored in the interpolator + * \param[in] yaml The yaml object that contains the map of unsigned integers to objects + * \param[in] key_name The name of the key in the yaml object + * \param[in] value_name The name of the value in the yaml object + * + * The yaml object is expected to be a list of maps. Each map has two or more + * pairs: one of \a key_name to the key value (usually color temperature), and + * one or more of \a value_name to the object. This is a bit difficult to + * explain, so here is an example (in python, as it is easier to parse than + * yaml): + * [ + * { + * 'ct': 2860, + * 'ccm': [ 2.12089, -0.52461, -0.59629, + * -0.85342, 2.80445, -0.95103, + * -0.26897, -1.14788, 2.41685 ], + * 'offsets': [ 0, 0, 0 ] + * }, + * + * { + * 'ct': 2960, + * 'ccm': [ 2.26962, -0.54174, -0.72789, + * -0.77008, 2.60271, -0.83262, + * -0.26036, -1.51254, 2.77289 ], + * 'offsets': [ 0, 0, 0 ] + * }, + * + * { + * 'ct': 3603, + * 'ccm': [ 2.18644, -0.66148, -0.52496, + * -0.77828, 2.69474, -0.91645, + * -0.25239, -0.83059, 2.08298 ], + * 'offsets': [ 0, 0, 0 ] + * }, + * ] + * + * In this case, \a key_name would be 'ct', and \a value_name can be either + * 'ccm' or 'offsets'. This way multiple interpolators can be defined in + * one set of color temperature ranges in the tuning file, and they can be + * retrieved separately with the \a value_name parameter. + * + * \return Zero on success, negative error code otherwise + */ + +/** + * \fn void Interpolator<T>::setQuantization(const unsigned int q) + * \brief Set the quantization value + * \param[in] q The quantization value + * + * Sets the quantization value. When this is set, 'key' gets quantized to this + * size, before doing the interpolation. This can help in reducing the number of + * updated pushed to the hardware. + * + * Note that normally a threshold needs to be combined with quantization. + * Otherwise a value that swings around the edge of the quantization step will + * lead to constant updates. + */ + +/** + * \fn void Interpolator<T>::setData(std::map<unsigned int, T> &&data) + * \brief Set the internal map + * + * Overwrites the internal map using move semantics. + */ + +/** + * \fn const T& Interpolator<T>::getInterpolated(unsigned int key, unsigned int *quantizedKey = nullptr) + * \brief Retrieve a a interpolated value for the given key + * \param[in] key The unsigned integer key of the object to retrieve + * \param[out] quantizedKey If provided, the key value after quantization + * \return The object corresponding to the key. The object is cached internally, + * so on successive calls with the same key (after quantization) interpolation + * is not recalculated. + */ + +/** + * \fn void Interpolator<T>::interpolate(const T &a, const T &b, T &dest, double + * lambda) + * \brief Interpolate between two instances of T + * \param a The first value to interpolate + * \param b The second value to interpolate + * \param dest The destination for the interpolated value + * \param lambda The interpolation factor (0..1) + * + * Interpolates between a and b according to lambda. It calculates dest = a * + * (1.0 - lambda) + b * lambda; + * + * If T supports multiplication with double and addition, this function can be + * used as is. For other types this function can be overwritten using partial + * template specialization. + */ + +} /* namespace ipa */ + +} /* namespace libcamera */ diff --git a/src/ipa/libipa/interpolator.h b/src/ipa/libipa/interpolator.h new file mode 100644 index 000000000000..fffce21465fe --- /dev/null +++ b/src/ipa/libipa/interpolator.h @@ -0,0 +1,131 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +/* + * Copyright (C) 2024, Paul Elder <paul.elder@ideasonboard.com> + * + * Helper class for interpolating maps of objects + */ + +#pragma once + +#include <algorithm> +#include <cmath> +#include <map> +#include <string> +#include <tuple> + +#include <libcamera/base/log.h> + +#include "libcamera/internal/yaml_parser.h" + +namespace libcamera { + +LOG_DECLARE_CATEGORY(Interpolator) + +namespace ipa { + +template<typename T> +class Interpolator +{ +public: + Interpolator() = default; + Interpolator(const std::map<unsigned int, T> &data) + : data_(data) + { + } + Interpolator(std::map<unsigned int, T> &&data) + : data_(std::move(data)) + { + } + + ~Interpolator() = default; + + int readYaml(const libcamera::YamlObject &yaml, + const std::string &key_name, + const std::string &value_name) + { + data_.clear(); + lastInterpolatedKey_.reset(); + + if (!yaml.isList()) { + LOG(Interpolator, Error) << "yaml object must be a list"; + return -EINVAL; + } + + for (const auto &value : yaml.asList()) { + unsigned int ct = std::stoul(value[key_name].get<std::string>("")); + std::optional<T> data = + value[value_name].get<T>(); + if (!data) { + return -EINVAL; + } + + data_[ct] = *data; + } + + if (data_.size() < 1) { + LOG(Interpolator, Error) << "Need at least one element"; + return -EINVAL; + } + + return 0; + } + + void setQuantization(const unsigned int q) + { + quantization_ = q; + } + + void setData(std::map<unsigned int, T> &&data) + { + data_ = std::move(data); + lastInterpolatedKey_.reset(); + } + + const T &getInterpolated(unsigned int key, unsigned int *quantizedKey = nullptr) + { + ASSERT(data_.size() > 0); + + if (quantization_ > 0) + key = std::lround(key / static_cast<double>(quantization_)) * quantization_; + + if (quantizedKey) + *quantizedKey = key; + + if (lastInterpolatedKey_.has_value() && + *lastInterpolatedKey_ == key) + return lastInterpolatedValue_; + + auto it = data_.lower_bound(key); + + if (it == data_.begin()) + return it->second; + + if (it == data_.end()) + return std::prev(it)->second; + + if (it->first == key) + return it->second; + + auto it2 = std::prev(it); + double lambda = (key - it2->first) / static_cast<double>(it->first - it2->first); + interpolate(it2->second, it->second, lastInterpolatedValue_, lambda); + lastInterpolatedKey_ = key; + + return lastInterpolatedValue_; + } + + void interpolate(const T &a, const T &b, T &dest, double lambda) + { + dest = a * (1.0 - lambda) + b * lambda; + } + +private: + std::map<unsigned int, T> data_; + T lastInterpolatedValue_; + std::optional<unsigned int> lastInterpolatedKey_; + unsigned int quantization_ = 0; +}; + +} /* namespace ipa */ + +} /* namespace libcamera */ diff --git a/src/ipa/libipa/meson.build b/src/ipa/libipa/meson.build index eff8ce2660f1..2c2712a7d252 100644 --- a/src/ipa/libipa/meson.build +++ b/src/ipa/libipa/meson.build @@ -7,6 +7,7 @@ libipa_headers = files([ 'exposure_mode_helper.h', 'fc_queue.h', 'histogram.h', + 'interpolator.h', 'matrix.h', 'matrix_interpolator.h', 'module.h', @@ -21,6 +22,7 @@ libipa_sources = files([ 'exposure_mode_helper.cpp', 'fc_queue.cpp', 'histogram.cpp', + 'interpolator.cpp', 'matrix.cpp', 'matrix_interpolator.cpp', 'module.cpp',
The MatrixInterpolator is great for interpolation of matrices for different color temperatures. It has however one limitation - it can only handle matrices. For LSC it would be great to interpolate the LSC tables (or even polynomials) using the same approach. Add a generic Interpolator class based on the existing MatrixInterpolator. This calss can be adapted to any other type using partial template specialization. Signed-off-by: Stefan Klug <stefan.klug@ideasonboard.com> --- src/ipa/libipa/interpolator.cpp | 156 ++++++++++++++++++++++++++++++++ src/ipa/libipa/interpolator.h | 131 +++++++++++++++++++++++++++ src/ipa/libipa/meson.build | 2 + 3 files changed, 289 insertions(+) create mode 100644 src/ipa/libipa/interpolator.cpp create mode 100644 src/ipa/libipa/interpolator.h