From patchwork Thu Jan 8 16:05:56 2026 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Klug X-Patchwork-Id: 25703 Return-Path: X-Original-To: parsemail@patchwork.libcamera.org Delivered-To: parsemail@patchwork.libcamera.org Received: from lancelot.ideasonboard.com (lancelot.ideasonboard.com [92.243.16.209]) by patchwork.libcamera.org (Postfix) with ESMTPS id 53488BE08B for ; Thu, 8 Jan 2026 16:07:06 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id 0496461FDE; Thu, 8 Jan 2026 17:07:06 +0100 (CET) Authentication-Results: lancelot.ideasonboard.com; dkim=pass (1024-bit key; unprotected) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="HmkYpdcH"; dkim-atps=neutral Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id BBBD961FC5 for ; Thu, 8 Jan 2026 17:07:04 +0100 (CET) Received: from ideasonboard.com (unknown [IPv6:2a00:6020:448c:6c00:90af:8957:b721:10d4]) by perceval.ideasonboard.com (Postfix) with UTF8SMTPSA id 1BF5326D2; Thu, 8 Jan 2026 17:06:42 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1767888402; bh=rsFrVOVU+1EDCj1TbjsOHC9KGpb7qZR65YvDwV3jm6I=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=HmkYpdcHA9gxx6Eu9ZEn49ghGLVmznibieWa/nV+eT8ub4Wb5wd6bKqLFZkB9xR/l iEpFvHqVWt9ntyA8BIqxlbQZTuwPtlwhXu1eeOMa7MilZp5OHzX4xe6WWN/xekcM5h AsPXEmSSuTPlBdI5UIdNqUuL/soQJb/OdjQI90k0= From: Stefan Klug Date: Thu, 08 Jan 2026 17:05:56 +0100 Subject: [PATCH v2 13/15] ipa: rkisp1: lsc: Resample polynomial lens shading tables at configure time MIME-Version: 1.0 Message-Id: <20260108-sklug-lsc-resampling-v2-dev-v2-13-e682ec4b9893@ideasonboard.com> References: <20260108-sklug-lsc-resampling-v2-dev-v2-0-e682ec4b9893@ideasonboard.com> In-Reply-To: <20260108-sklug-lsc-resampling-v2-dev-v2-0-e682ec4b9893@ideasonboard.com> To: libcamera-devel@lists.libcamera.org Cc: Stefan Klug X-Mailer: b4 0.14.2 X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libcamera-devel-bounces@lists.libcamera.org Sender: "libcamera-devel" The lens shading correction is always applied based on the sensor crop bounds. This leads to incorrect lens shading correction for analog crops that do not cover the whole sensor. To fix that, we need to adapt the lens shading table for the selected analog crop at configure time. Introduce an abstract ShadingDescriptor class that holds the lens shading information that can then be sampled at configure time for a specific crop rectangle. Resampling for a specific crop is only implemented for polynomial lsc data. For tabular data, a warning is logged and the unmodified table is returned. This matches the current functionality for tabular data and is a huge improvement for polynomial data. Signed-off-by: Stefan Klug --- Changes in v2: - Replaced "auto const" by "const auto" - Replaces some vector parameters by Spans - Changed sampleForCrop to return the components - Replaced min/max by clamp - Replaced map.swap() by move assignment --- src/ipa/rkisp1/algorithms/lsc.cpp | 233 ++++++++++++++++++++++++-------------- src/ipa/rkisp1/algorithms/lsc.h | 13 +++ 2 files changed, 159 insertions(+), 87 deletions(-) diff --git a/src/ipa/rkisp1/algorithms/lsc.cpp b/src/ipa/rkisp1/algorithms/lsc.cpp index a5855f8a0a67a6b5ad95635454f3716d07c86e6f..698f07b85bfa5d3de0c454087bf8e0874d85add7 100644 --- a/src/ipa/rkisp1/algorithms/lsc.cpp +++ b/src/ipa/rkisp1/algorithms/lsc.cpp @@ -72,38 +72,127 @@ namespace { constexpr int kColourTemperatureChangeThreshhold = 10; -class LscPolynomialLoader +class LscPolynomialShadingDescriptor : public LensShadingCorrection::ShadingDescriptor { public: - LscPolynomialLoader(const Size &sensorSize, - const Rectangle &cropRectangle, - const std::vector &xSizes, - const std::vector &ySizes) - : sensorSize_(sensorSize), - cropRectangle_(cropRectangle), - xSizes_(xSizes), - ySizes_(ySizes) + LscPolynomialShadingDescriptor(const LscPolynomial &pr, const LscPolynomial &pgr, + const LscPolynomial &pgb, const LscPolynomial &pb) + : pr_(pr), pgr_(pgr), pgb_(pgb), pb_(pb) { } - int parseLscData(const YamlObject &yamlSets, - std::map &lscData); + LensShadingCorrection::Components sampleForCrop(const Rectangle &cropRectangle, + Span xSizes, + Span ySizes) override; private: - std::vector sizesListToPositions(const std::vector &sizes); std::vector samplePolynomial(const LscPolynomial &poly, Span xPositions, Span yPositions, const Rectangle &cropRectangle); + std::vector sizesListToPositions(Span sizes); + + LscPolynomial pr_; + LscPolynomial pgr_; + LscPolynomial pgb_; + LscPolynomial pb_; +}; + +LensShadingCorrection::Components +LscPolynomialShadingDescriptor::sampleForCrop(const Rectangle &cropRectangle, + Span xSizes, + Span ySizes) +{ + std::vector xPos = sizesListToPositions(xSizes); + std::vector yPos = sizesListToPositions(ySizes); + + return { + .r = samplePolynomial(pr_, xPos, yPos, cropRectangle), + .gr = samplePolynomial(pgr_, xPos, yPos, cropRectangle), + .gb = samplePolynomial(pgb_, xPos, yPos, cropRectangle), + .b = samplePolynomial(pb_, xPos, yPos, cropRectangle) + }; +} + +std::vector +LscPolynomialShadingDescriptor::samplePolynomial(const LscPolynomial &poly, + Span xPositions, + Span yPositions, + const Rectangle &cropRectangle) +{ + double m = poly.getM(); + double x0 = cropRectangle.x / m; + double y0 = cropRectangle.y / m; + double w = cropRectangle.width / m; + double h = cropRectangle.height / m; + std::vector samples; + + samples.reserve(xPositions.size() * yPositions.size()); + + for (double y : yPositions) { + for (double x : xPositions) { + double xp = x0 + x * w; + double yp = y0 + y * h; + /* + * The hardware uses 2.10 fixed point format and limits + * the legal values to [1..3.999]. Scale and clamp the + * sampled value accordingly. + */ + int v = static_cast( + poly.sampleAtNormalizedPixelPos(xp, yp) * + 1024); + v = std::clamp(v, 1024, 4095); + samples.push_back(v); + } + } + return samples; +} + +/* + * The rkisp1 LSC grid spacing is defined by the cell sizes on the first half of + * the grid. This is then mirrored in hardware to the other half. See + * parseSizes() for further details. For easier handling, this function converts + * the cell sizes of half the grid to a list of position of the whole grid (on + * one axis). Example: + * + * input: | 0.2 | 0.3 | + * output: 0.0 0.2 0.5 0.8 1.0 + */ +std::vector +LscPolynomialShadingDescriptor::sizesListToPositions(Span sizes) +{ + const int half = sizes.size(); + std::vector positions(half * 2 + 1); + double x = 0.0; + + positions[half] = 0.5; + for (int i = 1; i <= half; i++) { + x += sizes[half - i]; + positions[half - i] = 0.5 - x; + positions[half + i] = 0.5 + x; + } + + return positions; +} + +class LscPolynomialLoader +{ +public: + LscPolynomialLoader(const Size &sensorSize) + : sensorSize_(sensorSize) + { + } + + int parseLscData(const YamlObject &yamlSets, + LensShadingCorrection::ShadingDescriptorMap &lscData); + +private: Size sensorSize_; - Rectangle cropRectangle_; - const std::vector &xSizes_; - const std::vector &ySizes_; }; int LscPolynomialLoader::parseLscData(const YamlObject &yamlSets, - std::map &lscData) + LensShadingCorrection::ShadingDescriptorMap &lscData) { const auto &sets = yamlSets.asList(); for (const auto &yamlSet : sets) { @@ -117,7 +206,6 @@ int LscPolynomialLoader::parseLscData(const YamlObject &yamlSets, return -EINVAL; } - LensShadingCorrection::Components &set = lscData[ct]; pr = yamlSet["r"].get(); pgr = yamlSet["gr"].get(); pgb = yamlSet["gb"].get(); @@ -135,12 +223,9 @@ int LscPolynomialLoader::parseLscData(const YamlObject &yamlSets, pgb->setReferenceImageSize(sensorSize_); pb->setReferenceImageSize(sensorSize_); - std::vector xPos = sizesListToPositions(xSizes_); - std::vector yPos = sizesListToPositions(ySizes_); - set.r = samplePolynomial(*pr, xPos, yPos, cropRectangle_); - set.gr = samplePolynomial(*pgr, xPos, yPos, cropRectangle_); - set.gb = samplePolynomial(*pgb, xPos, yPos, cropRectangle_); - set.b = samplePolynomial(*pb, xPos, yPos, cropRectangle_); + lscData.emplace( + ct, std::make_unique( + *pr, *pgr, *pgb, *pb)); } if (lscData.empty()) { @@ -151,70 +236,33 @@ int LscPolynomialLoader::parseLscData(const YamlObject &yamlSets, return 0; } -/* - * The rkisp1 LSC grid spacing is defined by the cell sizes on the first half of - * the grid. This is then mirrored in hardware to the other half. See - * parseSizes() for further details. For easier handling, this function converts - * the cell sizes of half the grid to a list of position of the whole grid (on - * one axis). Example: - * - * input: | 0.2 | 0.3 | - * output: 0.0 0.2 0.5 0.8 1.0 - */ -std::vector LscPolynomialLoader::sizesListToPositions(const std::vector &sizes) +class LscTableShadingDescriptor : public LensShadingCorrection::ShadingDescriptor { - const int half = sizes.size(); - std::vector positions(half * 2 + 1); - double x = 0.0; - - positions[half] = 0.5; - for (int i = 1; i <= half; i++) { - x += sizes[half - i]; - positions[half - i] = 0.5 - x; - positions[half + i] = 0.5 + x; +public: + LscTableShadingDescriptor(LensShadingCorrection::Components components) + : lscData_(std::move(components)) + { } - return positions; -} - -std::vector LscPolynomialLoader::samplePolynomial(const LscPolynomial &poly, - Span xPositions, - Span yPositions, - const Rectangle &cropRectangle) -{ - double m = poly.getM(); - double x0 = cropRectangle.x / m; - double y0 = cropRectangle.y / m; - double w = cropRectangle.width / m; - double h = cropRectangle.height / m; - std::vector samples; - - samples.reserve(xPositions.size() * yPositions.size()); - - for (double y : yPositions) { - for (double x : xPositions) { - double xp = x0 + x * w; - double yp = y0 + y * h; - /* - * The hardware uses 2.10 fixed point format and limits - * the legal values to [1..3.999]. Scale and clamp the - * sampled value accordingly. - */ - int v = static_cast( - poly.sampleAtNormalizedPixelPos(xp, yp) * - 1024); - v = std::min(std::max(v, 1024), 4095); - samples.push_back(v); - } + LensShadingCorrection::Components + sampleForCrop([[maybe_unused]] const Rectangle &cropRectangle, + [[maybe_unused]] Span xSizes, + [[maybe_unused]] Span ySizes) + { + LOG(RkISP1Lsc, Warning) + << "Tabular LSC data doesn't support resampling."; + return lscData_; } - return samples; -} + +private: + LensShadingCorrection::Components lscData_; +}; class LscTableLoader { public: int parseLscData(const YamlObject &yamlSets, - std::map &lscData); + LensShadingCorrection::ShadingDescriptorMap &lscData); private: std::vector parseTable(const YamlObject &tuningData, @@ -222,7 +270,7 @@ private: }; int LscTableLoader::parseLscData(const YamlObject &yamlSets, - std::map &lscData) + LensShadingCorrection::ShadingDescriptorMap &lscData) { const auto &sets = yamlSets.asList(); @@ -236,8 +284,7 @@ int LscTableLoader::parseLscData(const YamlObject &yamlSets, return -EINVAL; } - LensShadingCorrection::Components &set = lscData[ct]; - + LensShadingCorrection::Components set; set.r = parseTable(yamlSet, "r"); set.gr = parseTable(yamlSet, "gr"); set.gb = parseTable(yamlSet, "gb"); @@ -250,6 +297,9 @@ int LscTableLoader::parseLscData(const YamlObject &yamlSets, << " is missing tables"; return -EINVAL; } + + lscData.emplace( + ct, std::make_unique(std::move(set))); } if (lscData.empty()) { @@ -341,7 +391,7 @@ int LensShadingCorrection::init([[maybe_unused]] IPAContext &context, return -EINVAL; } - std::map lscData; + ShadingDescriptorMap lscData; int ret = 0; std::string type = tuningData["type"].get("table"); @@ -351,10 +401,11 @@ int LensShadingCorrection::init([[maybe_unused]] IPAContext &context, ret = loader.parseLscData(yamlSets, lscData); } else if (type == "polynomial") { LOG(RkISP1Lsc, Debug) << "Loading polynomial LSC data."; - auto loader = LscPolynomialLoader(context.sensorInfo.activeAreaSize, - context.sensorInfo.analogCrop, - xSize_, - ySize_); + /* + * \todo: Most likely the reference frame should be native_size. + * Let's wait how the internal discussions progress. + */ + auto loader = LscPolynomialLoader(context.sensorInfo.activeAreaSize); ret = loader.parseLscData(yamlSets, lscData); } else { LOG(RkISP1Lsc, Error) << "Unsupported LSC data type '" @@ -365,7 +416,7 @@ int LensShadingCorrection::init([[maybe_unused]] IPAContext &context, if (ret) return ret; - sets_.setData(std::move(lscData)); + shadingDescriptors_ = std::move(lscData); return 0; } @@ -401,6 +452,14 @@ int LensShadingCorrection::configure(IPAContext &context, yGrad_[i] = std::round(32768 / ySizes_[i]); } + LOG(RkISP1Lsc, Debug) << "Sample LSC data for " << configInfo.analogCrop; + std::map shadingData; + for (const auto &[t, descriptor] : shadingDescriptors_) + shadingData[t] = descriptor->sampleForCrop(configInfo.analogCrop, + xSize_, ySize_); + + sets_.setData(std::move(shadingData)); + context.configuration.lsc.enabled = true; return 0; } diff --git a/src/ipa/rkisp1/algorithms/lsc.h b/src/ipa/rkisp1/algorithms/lsc.h index 7b68dda1a0d4257c345e0f1b77aa498f8183c92f..3097740a6cb2ce9063a4ba087856987a489b0ab6 100644 --- a/src/ipa/rkisp1/algorithms/lsc.h +++ b/src/ipa/rkisp1/algorithms/lsc.h @@ -8,6 +8,7 @@ #pragma once #include +#include #include "libipa/interpolator.h" @@ -36,10 +37,22 @@ public: std::vector b; }; + class ShadingDescriptor + { + public: + virtual ~ShadingDescriptor() = default; + virtual Components sampleForCrop(const Rectangle &cropRectangle, + Span xSizes, + Span ySizes) = 0; + }; + + using ShadingDescriptorMap = std::map>; + private: void setParameters(rkisp1_cif_isp_lsc_config &config); void copyTable(rkisp1_cif_isp_lsc_config &config, const Components &set0); + ShadingDescriptorMap shadingDescriptors_; ipa::Interpolator sets_; std::vector xSize_; std::vector ySize_;