[PATCH v4 3/3] ipa: rkisp1: Add GammaOutCorrection algorithm
Paul Elder
paul.elder at ideasonboard.com
Mon Jun 10 14:41:50 CEST 2024
On Wed, Jun 05, 2024 at 11:53:51AM +0200, Stefan Klug wrote:
> Add a gamma algorithm for the rkisp1. It defaults to a gamma of 2.2 which
> closely resembles sRGB. No seperate sRGB mode was implemented because the pwl
> that models the gamma curve is so coarse that there is basically no difference
> between srgb and gamma=2.2. The default can be overridden within the tuning
> file or set at runtime using the gamma control.
>
> The gamma algorithm is not enabled by default. This will be done in future
> tuning file updates.
>
> Signed-off-by: Stefan Klug <stefan.klug at ideasonboard.com>
> Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> ---
> src/ipa/rkisp1/algorithms/goc.cpp | 153 ++++++++++++++++++++++++++
> src/ipa/rkisp1/algorithms/goc.h | 42 +++++++
> src/ipa/rkisp1/algorithms/meson.build | 1 +
> src/ipa/rkisp1/ipa_context.h | 9 ++
> 4 files changed, 205 insertions(+)
> create mode 100644 src/ipa/rkisp1/algorithms/goc.cpp
> create mode 100644 src/ipa/rkisp1/algorithms/goc.h
>
> diff --git a/src/ipa/rkisp1/algorithms/goc.cpp b/src/ipa/rkisp1/algorithms/goc.cpp
> new file mode 100644
> index 000000000000..ab634c1c9709
> --- /dev/null
> +++ b/src/ipa/rkisp1/algorithms/goc.cpp
> @@ -0,0 +1,153 @@
> +/* SPDX-License-Identifier: LGPL-2.1-or-later */
> +/*
> + * Copyright (C) 2024, Ideas On Board
> + *
> + * RkISP1 Gamma out control
> + */
> +#include "goc.h"
> +
> +#include <cmath>
> +
> +#include <libcamera/base/log.h>
> +#include <libcamera/base/utils.h>
> +
> +#include <libcamera/control_ids.h>
> +
> +#include "libcamera/internal/yaml_parser.h"
> +
> +#include "linux/rkisp1-config.h"
> +
> +/**
> + * \file goc.h
> + */
> +
> +namespace libcamera {
> +
> +namespace ipa::rkisp1::algorithms {
> +
> +/**
> + * \class GammaOutCorrection
> + * \brief RkISP1 Gamma out correction
> + *
> + * This algorithm implements the gamma out curve for the RkISP1.
> + * It defaults to a gamma value of 2.2
> + * As gamma is internally represented as a piecewise linear function with only
> + * 17 knots, the difference between gamma=2.2 and sRGB gamma is minimal.
> + * Therefore sRGB gamma was not implemented as special case.
> + *
> + * Useful links:
> + * https://www.cambridgeincolour.com/tutorials/gamma-correction.htm
> + * https://en.wikipedia.org/wiki/SRGB
> + */
> +
> +LOG_DEFINE_CATEGORY(RkISP1Gamma)
> +
> +const float kDefaultGamma = 2.2f;
> +
> +/**
> + * \copydoc libcamera::ipa::Algorithm::init
> + */
> +int GammaOutCorrection::init([[maybe_unused]] IPAContext &context,
> + [[maybe_unused]] const YamlObject &tuningData)
> +{
> + if (context.hw->numGammaOutSamples !=
> + RKISP1_CIF_ISP_GAMMA_OUT_MAX_SAMPLES_V10) {
> + LOG(RkISP1Gamma, Error)
> + << "Gamma is not implemented for RkISP1 V12";
> + return -EINVAL;
> + }
> +
> + context.ctrlMap[&controls::Gamma] = ControlInfo(0.1f, 10.0f, kDefaultGamma);
> + defaultGamma_ = tuningData["gamma"].get<double>(kDefaultGamma);
I think these should be switched so that the default gamma that's read
from the tuning file will be set as the default gamma in the
ControlInfo. Otherwise the default that's set and reported via metadata
wouldn't be consistent with the default that's reported in the
ControlInfo.
With that changed:
Reviewed-by: Paul Elder <paul.elder at ideasonboard.com>
> +
> + return 0;
> +}
> +
> +/**
> + * \brief Configure the Gamma given a configInfo
> + * \param[in] context The shared IPA context
> + * \param[in] configInfo The IPA configuration data
> + *
> + * \return 0
> + */
> +int GammaOutCorrection::configure(IPAContext &context,
> + [[maybe_unused]] const IPACameraSensorInfo &configInfo)
> +{
> + context.activeState.goc.gamma = defaultGamma_;
> + return 0;
> +}
> +
> +/**
> + * \copydoc libcamera::ipa::Algorithm::queueRequest
> + */
> +void GammaOutCorrection::queueRequest([[maybe_unused]] IPAContext &context,
> + [[maybe_unused]] const uint32_t frame,
> + IPAFrameContext &frameContext,
> + const ControlList &controls)
> +{
> + if (frame == 0)
> + frameContext.goc.update = true;
> +
> + const auto &gamma = controls.get(controls::Gamma);
> + if (gamma) {
> + context.activeState.goc.gamma = *gamma;
> + frameContext.goc.update = true;
> + LOG(RkISP1Gamma, Debug) << "Set gamma to " << *gamma;
> + }
> +
> + frameContext.goc.gamma = context.activeState.goc.gamma;
> +}
> +
> +/**
> + * \copydoc libcamera::ipa::Algorithm::prepare
> + */
> +void GammaOutCorrection::prepare([[maybe_unused]] IPAContext &context,
> + [[maybe_unused]] const uint32_t frame,
> + [[maybe_unused]] IPAFrameContext &frameContext,
> + rkisp1_params_cfg *params)
> +{
> + ASSERT(context.hw->numGammaOutSamples ==
> + RKISP1_CIF_ISP_GAMMA_OUT_MAX_SAMPLES_V10);
> +
> + /*
> + * The logarithmic segments as specified in the reference.
> + * Plus an additional 0 to make the loop easier
> + */
> + std::array<unsigned, RKISP1_CIF_ISP_GAMMA_OUT_MAX_SAMPLES_V10> segments = {
> + 64, 64, 64, 64, 128, 128, 128, 128, 256,
> + 256, 256, 512, 512, 512, 512, 512, 0
> + };
> + auto gamma_y = params->others.goc_config.gamma_y;
> +
> + if (!frameContext.goc.update)
> + return;
> +
> + unsigned x = 0;
> + for (const auto [i, size] : utils::enumerate(segments)) {
> + gamma_y[i] = std::pow(x / 4096.0, 1.0 / frameContext.goc.gamma) * 1023.0;
> + x += size;
> + }
> +
> + params->others.goc_config.mode = RKISP1_CIF_ISP_GOC_MODE_LOGARITHMIC;
> + params->module_cfg_update |= RKISP1_CIF_ISP_MODULE_GOC;
> + params->module_en_update |= RKISP1_CIF_ISP_MODULE_GOC;
> + params->module_ens |= RKISP1_CIF_ISP_MODULE_GOC;
> +}
> +
> +/**
> + * \copydoc libcamera::ipa::Algorithm::process
> + */
> +void GammaOutCorrection::process([[maybe_unused]] IPAContext &context,
> + [[maybe_unused]] const uint32_t frame,
> + IPAFrameContext &frameContext,
> + [[maybe_unused]] const rkisp1_stat_buffer *stats,
> + ControlList &metadata)
> +{
> + metadata.set(controls::Gamma, frameContext.goc.gamma);
> +}
> +
> +REGISTER_IPA_ALGORITHM(GammaOutCorrection, "GammaOutCorrection")
> +
> +} /* namespace ipa::rkisp1::algorithms */
> +
> +} /* namespace libcamera */
> diff --git a/src/ipa/rkisp1/algorithms/goc.h b/src/ipa/rkisp1/algorithms/goc.h
> new file mode 100644
> index 000000000000..3be8e500be67
> --- /dev/null
> +++ b/src/ipa/rkisp1/algorithms/goc.h
> @@ -0,0 +1,42 @@
> +/* SPDX-License-Identifier: LGPL-2.1-or-later */
> +/*
> + * Copyright (C) 2024, Ideas On Board
> + *
> + * RkISP1 Gamma out control
> + */
> +
> +#pragma once
> +
> +#include "algorithm.h"
> +
> +namespace libcamera {
> +
> +namespace ipa::rkisp1::algorithms {
> +
> +class GammaOutCorrection : public Algorithm
> +{
> +public:
> + GammaOutCorrection() = default;
> + ~GammaOutCorrection() = default;
> +
> + int init(IPAContext &context, const YamlObject &tuningData) override;
> + int configure(IPAContext &context,
> + const IPACameraSensorInfo &configInfo) override;
> + void queueRequest(IPAContext &context,
> + const uint32_t frame,
> + IPAFrameContext &frameContext,
> + const ControlList &controls) override;
> + void prepare(IPAContext &context, const uint32_t frame,
> + IPAFrameContext &frameContext,
> + rkisp1_params_cfg *params) override;
> + void process(IPAContext &context, const uint32_t frame,
> + IPAFrameContext &frameContext,
> + const rkisp1_stat_buffer *stats,
> + ControlList &metadata) override;
> +
> +private:
> + double defaultGamma_;
> +};
> +
> +} /* namespace ipa::rkisp1::algorithms */
> +} /* namespace libcamera */
> diff --git a/src/ipa/rkisp1/algorithms/meson.build b/src/ipa/rkisp1/algorithms/meson.build
> index 93a483292753..6ee71a9b5da3 100644
> --- a/src/ipa/rkisp1/algorithms/meson.build
> +++ b/src/ipa/rkisp1/algorithms/meson.build
> @@ -8,6 +8,7 @@ rkisp1_ipa_algorithms = files([
> 'dpcc.cpp',
> 'dpf.cpp',
> 'filter.cpp',
> + 'goc.cpp',
> 'gsl.cpp',
> 'lsc.cpp',
> ])
> diff --git a/src/ipa/rkisp1/ipa_context.h b/src/ipa/rkisp1/ipa_context.h
> index bd02a7a24fdd..f261e42fc2fd 100644
> --- a/src/ipa/rkisp1/ipa_context.h
> +++ b/src/ipa/rkisp1/ipa_context.h
> @@ -104,6 +104,10 @@ struct IPAActiveState {
> uint8_t denoise;
> uint8_t sharpness;
> } filter;
> +
> + struct {
> + double gamma;
> + } goc;
> };
>
> struct IPAFrameContext : public FrameContext {
> @@ -146,6 +150,11 @@ struct IPAFrameContext : public FrameContext {
> uint32_t exposure;
> double gain;
> } sensor;
> +
> + struct {
> + double gamma;
> + bool update;
> + } goc;
> };
>
> struct IPAContext {
> --
> 2.43.0
>
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