[PATCH v2 09/10] ipa: mali-c55: Add Lens Shading Correction algorithm
Kieran Bingham
kieran.bingham at ideasonboard.com
Wed Oct 9 17:43:59 CEST 2024
Quoting Daniel Scally (2024-07-09 15:49:49)
> Add a lens shading correction algorithm to the mali-c55 IPA. This
> algorithm parses tables from Yaml in a easy to follow format before
> munging them into Arm's interleaved mesh to be copied to the ISP.
> A colour temperature estimate from the AGC statistics is used to
> select the appropriate table to apply; this can be some interpolation
> of two tables, in which case the colour temperature estimate is also
> used to derive the coefficient that does the blending.
>
> Acked-by: Nayden Kanchev <nayden.kanchev at arm.com>
> Co-developed-by: Jacopo Mondi <jacopo.mondi at ideasonboard.com>
> Signed-off-by: Jacopo Mondi <jacopo.mondi at ideasonboard.com>
> Signed-off-by: Daniel Scally <dan.scally at ideasonboard.com>
> ---
> Changes in v2:
>
> - Use the union rather than reinterpret_cast<>() to abstract the block
>
> src/ipa/mali-c55/algorithms/lsc.cpp | 216 ++++++++++++++++++++++++
> src/ipa/mali-c55/algorithms/lsc.h | 45 +++++
> src/ipa/mali-c55/algorithms/meson.build | 1 +
> 3 files changed, 262 insertions(+)
> create mode 100644 src/ipa/mali-c55/algorithms/lsc.cpp
> create mode 100644 src/ipa/mali-c55/algorithms/lsc.h
>
> diff --git a/src/ipa/mali-c55/algorithms/lsc.cpp b/src/ipa/mali-c55/algorithms/lsc.cpp
> new file mode 100644
> index 00000000..8d574779
> --- /dev/null
> +++ b/src/ipa/mali-c55/algorithms/lsc.cpp
> @@ -0,0 +1,216 @@
> +/* SPDX-License-Identifier: LGPL-2.1-or-later */
> +/*
> + * Copyright (C) 2024, Ideas On Board Oy
> + *
> + * lsc.cpp - Mali-C55 Lens shading correction algorithm
> + */
> +
> +#include "lsc.h"
> +
> +#include "libcamera/internal/yaml_parser.h"
> +
> +namespace libcamera {
> +
> +namespace ipa::mali_c55::algorithms {
> +
> +LOG_DEFINE_CATEGORY(MaliC55Lsc)
> +
> +Lsc::Lsc()
> +{
> +}
I don't think we need to declare emtpy/default constructors?
> +
> +int Lsc::init([[maybe_unused]] IPAContext &context, const YamlObject &tuningData)
> +{
> + if (!tuningData.contains("meshScale")) {
> + LOG(MaliC55Lsc, Error) << "meshScale missing from tuningData";
> + return -EINVAL;
> + }
> +
> + meshScale_ = tuningData["meshScale"].get<uint32_t>(0);
> +
> + const YamlObject &yamlSets = tuningData["sets"];
> + if (!yamlSets.isList()) {
> + LOG(MaliC55Lsc, Error) << "LSC tables missing or invalid";
> + return -EINVAL;
> + }
> +
> + size_t tableSize = 0;
> + const auto &sets = yamlSets.asList();
> + for (const auto &yamlSet : sets) {
> + uint32_t ct = yamlSet["ct"].get<uint32_t>(0);
> +
> + if (!ct) {
> + LOG(MaliC55Lsc, Error) << "Invalid colour temperature";
> + return -EINVAL;
> + }
> +
> + if (std::count(colourTemperatures_.begin(),
> + colourTemperatures_.end(), ct)) {
> + LOG(MaliC55Lsc, Error)
> + << "Multiple sets found for colour temperature";
> + return -EINVAL;
> + }
> +
> + std::vector<uint8_t> rTable =
> + yamlSet["r"].getList<uint8_t>().value_or(std::vector<uint8_t>{});
> + std::vector<uint8_t> gTable =
> + yamlSet["g"].getList<uint8_t>().value_or(std::vector<uint8_t>{});
> + std::vector<uint8_t> bTable =
> + yamlSet["b"].getList<uint8_t>().value_or(std::vector<uint8_t>{});
> +
> + /*
> + * Some validation to do; only 16x16 and 32x32 tables of
> + * coefficients are acceptable, and all tables across all of the
> + * sets must be the same size. The first time we encounter a
> + * table we check that it is an acceptable size and if so make
> + * sure all other tables are of equal size.
> + */
> + if (!tableSize) {
> + if (rTable.size() != 256 && rTable.size() != 1024) {
> + LOG(MaliC55Lsc, Error)
> + << "Invalid table size for colour temperature " << ct;
> + return -EINVAL;
> + }
> + tableSize = rTable.size();
> + }
> +
> + if (rTable.size() != tableSize ||
> + gTable.size() != tableSize ||
> + bTable.size() != tableSize) {
> + LOG(MaliC55Lsc, Error)
> + << "Invalid or mismatched table size for colour temperature " << ct;
> + return -EINVAL;
> + }
> +
> + if (colourTemperatures_.size() >= 3) {
> + LOG(MaliC55Lsc, Error)
> + << "A maximum of 3 colour temperatures are supported";
> + return -EINVAL;
> + }
> +
> + for (unsigned int i = 0; i < tableSize; i++) {
> + mesh_[kRedOffset + i] |=
> + (rTable[i] << (colourTemperatures_.size() * 8));
> + mesh_[kGreenOffset + i] |=
> + (gTable[i] << (colourTemperatures_.size() * 8));
> + mesh_[kBlueOffset + i] |=
> + (bTable[i] << (colourTemperatures_.size() * 8));
> + }
> +
> + colourTemperatures_.push_back(ct);
> + }
> +
A comment here about meshSize_ would be helpful. I have no idea what
this next block of code is doing or why.
Seems that's all I've got in here for now.
Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> + if (tableSize == 256)
> + meshSize_ = 15;
> + else
> + meshSize_ = 31;
> +
> + return 0;
> +}
> +
> +size_t Lsc::fillConfigParamsBlock(mali_c55_params_block block) const
> +{
> + block.header->type = MALI_C55_PARAM_MESH_SHADING_CONFIG;
> + block.header->enabled = true;
> + block.header->size = sizeof(struct mali_c55_params_mesh_shading_config);
> +
> + block.shading_config->mesh_show = false;
> + block.shading_config->mesh_scale = meshScale_;
> + block.shading_config->mesh_page_r = 0;
> + block.shading_config->mesh_page_g = 1;
> + block.shading_config->mesh_page_b = 2;
> + block.shading_config->mesh_width = meshSize_;
> + block.shading_config->mesh_height = meshSize_;
> +
> + std::copy(mesh_.begin(), mesh_.end(), block.shading_config->mesh);
> +
> + return block.header->size;
> +}
> +
> +size_t Lsc::fillSelectionParamsBlock(mali_c55_params_block block, uint8_t bank,
> + uint8_t alpha) const
> +{
> + block.header->type = MALI_C55_PARAM_MESH_SHADING_SELECTION;
> + block.header->enabled = true;
> + block.header->size = sizeof(struct mali_c55_params_mesh_shading_selection);
> +
> + block.shading_selection->mesh_alpha_bank_r = bank;
> + block.shading_selection->mesh_alpha_bank_g = bank;
> + block.shading_selection->mesh_alpha_bank_b = bank;
> + block.shading_selection->mesh_alpha_r = alpha;
> + block.shading_selection->mesh_alpha_g = alpha;
> + block.shading_selection->mesh_alpha_b = alpha;
> + block.shading_selection->mesh_strength = 0x1000; /* Otherwise known as 1.0 */
> +
> + return block.header->size;
> +}
> +
> +std::tuple<uint8_t, uint8_t> Lsc::findBankAndAlpha(uint32_t ct) const
> +{
> + unsigned int i;
> +
> + ct = std::clamp<uint32_t>(ct, colourTemperatures_.front(),
> + colourTemperatures_.back());
> +
> + for (i = 0; i < colourTemperatures_.size() - 1; i++) {
> + if (ct >= colourTemperatures_[i] &&
> + ct <= colourTemperatures_[i + 1])
> + break;
> + }
> +
> + /*
> + * With the clamping, we're guaranteed an index into colourTemperatures_
> + * that's <= colourTemperatures_.size() - 1.
> + */
> + uint8_t alpha = (255 * (ct - colourTemperatures_[i])) /
> + (colourTemperatures_[i + 1] - colourTemperatures_[i]);
> +
> + return { i, alpha };
> +}
> +
> +void Lsc::prepare(IPAContext &context, [[maybe_unused]] const uint32_t frame,
> + [[maybe_unused]] IPAFrameContext &frameContext,
> + mali_c55_params_buffer *params)
> +{
> + /*
> + * For each frame we assess the colour temperature of the **last** frame
> + * and then select an appropriately blended table of coefficients based
> + * on that ct. As a bit of a shortcut, if we've only a single table the
> + * handling is somewhat simpler; if it's the first frame we just select
> + * that table and if we're past the first frame then we can just do
> + * nothing - the config will never change.
> + */
> + uint32_t temperatureK = context.activeState.agc.temperatureK;
> + uint8_t bank, alpha;
> +
> + if (colourTemperatures_.size() == 1) {
> + if (frame > 0)
> + return;
> +
> + bank = 0;
> + alpha = 0;
> + } else {
> + std::tie(bank, alpha) = findBankAndAlpha(temperatureK);
> + }
> +
> + mali_c55_params_block block;
> + block.data = ¶ms->data[params->total_size];
> +
> + params->total_size += fillSelectionParamsBlock(block, bank, alpha);
> +
> + if (frame > 0)
> + return;
> +
> + /*
> + * If this is the first frame, we need to load the parsed coefficient
> + * tables from tuning data to the ISP.
> + */
> + block.data = ¶ms->data[params->total_size];
> + params->total_size += fillConfigParamsBlock(block);
> +}
> +
> +REGISTER_IPA_ALGORITHM(Lsc, "Lsc")
> +
> +} /* namespace ipa::mali_c55::algorithms */
> +
> +} /* namespace libcamera */
> diff --git a/src/ipa/mali-c55/algorithms/lsc.h b/src/ipa/mali-c55/algorithms/lsc.h
> new file mode 100644
> index 00000000..ed356f4a
> --- /dev/null
> +++ b/src/ipa/mali-c55/algorithms/lsc.h
> @@ -0,0 +1,45 @@
> +/* SPDX-License-Identifier: LGPL-2.1-or-later */
> +/*
> + * Copyright (C) 2024, Ideas On Board Oy
> + *
> + * lsc.h - Mali-C55 Lens shading correction algorithm
> + */
> +
> +#include <map>
> +#include <tuple>
> +
> +#include "algorithm.h"
> +
> +namespace libcamera {
> +
> +namespace ipa::mali_c55::algorithms {
> +
> +class Lsc : public Algorithm
> +{
> +public:
> + Lsc();
> + ~Lsc() = default;
> +
> + int init(IPAContext &context, const YamlObject &tuningData) override;
> + void prepare(IPAContext &context, const uint32_t frame,
> + IPAFrameContext &frameContext,
> + mali_c55_params_buffer *params) override;
> +private:
> + static constexpr unsigned int kRedOffset = 0;
> + static constexpr unsigned int kGreenOffset = 1024;
> + static constexpr unsigned int kBlueOffset = 2048;
> +
> + size_t fillConfigParamsBlock(mali_c55_params_block block) const;
> + size_t fillSelectionParamsBlock(mali_c55_params_block block,
> + uint8_t bank, uint8_t alpha) const;
> + std::tuple<uint8_t, uint8_t> findBankAndAlpha(uint32_t ct) const;
> +
> + std::vector<uint32_t> mesh_ = std::vector<uint32_t>(3072);
> + std::vector<uint32_t> colourTemperatures_;
> + uint32_t meshScale_;
> + uint32_t meshSize_;
> +};
> +
> +} /* namespace ipa::mali_c55::algorithms */
> +
> +} /* namespace libcamera */
> diff --git a/src/ipa/mali-c55/algorithms/meson.build b/src/ipa/mali-c55/algorithms/meson.build
> index f11791aa..1665da07 100644
> --- a/src/ipa/mali-c55/algorithms/meson.build
> +++ b/src/ipa/mali-c55/algorithms/meson.build
> @@ -4,4 +4,5 @@ mali_c55_ipa_algorithms = files([
> 'agc.cpp',
> 'awb.cpp',
> 'blc.cpp',
> + 'lsc.cpp',
> ])
> --
> 2.34.1
>
More information about the libcamera-devel
mailing list