[{"id":37975,"web_url":"https://patchwork.libcamera.org/comment/37975/","msgid":"<20260127164458.GB2512313@killaraus>","date":"2026-01-27T16:44:58","subject":"Re: [PATCH v2] libcamera: simple: Fix black level offsets in AWB","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/people/2/","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"content":"On Tue, Jan 27, 2026 at 05:29:23PM +0100, Milan Zamazal wrote:\n> The black level offset subtracted in AWB is wrong. It assumes that the\n> stats contain sums of the individual colour pixels. But they actually\n> contain sums of the colour channels of larger \"superpixels\" consisting\n> of the individual colour pixels. Each of the RGB colour values and the\n> computed luminosity (a histogram entry) are added once to the stats per\n> such a superpixel. This means the offset computed from the black level\n> and the number of pixels should be used as it is, not divided.\n> \n> The patch fixes the subtracted offset. Since the evaluation is the same\n> for all the three colours now, the individual class variables are\n> replaced with a single RGB variable.\n> \n> Fixes: 4e13c6f55bd667 (\"Honor black level in AWB\")\n> Signed-off-by: Milan Zamazal \n\nReviewed-by: Laurent Pinchart \n\n> ---\n> .../internal/software_isp/swisp_stats.h | 16 +++++-----------\n> src/ipa/simple/algorithms/awb.cpp | 10 ++++------\n> src/libcamera/software_isp/swstats_cpu.cpp | 10 ++++------\n> 3 files changed, 13 insertions(+), 23 deletions(-)\n> \n> diff --git a/include/libcamera/internal/software_isp/swisp_stats.h b/include/libcamera/internal/software_isp/swisp_stats.h\n> index 3c9860185..d9d0d9be8 100644\n> --- a/include/libcamera/internal/software_isp/swisp_stats.h\n> +++ b/include/libcamera/internal/software_isp/swisp_stats.h\n> @@ -10,6 +10,8 @@\n> #include \n> #include \n> \n> +#include \"libcamera/internal/vector.h\"\n> +\n> namespace libcamera {\n> \n> /**\n> @@ -26,17 +28,9 @@ struct SwIspStats {\n> \t */\n> \tbool valid;\n> \t/**\n> -\t * \\brief Holds the sum of all sampled red pixels\n> -\t */\n> -\tuint64_t sumR_;\n> -\t/**\n> -\t * \\brief Holds the sum of all sampled green pixels\n> -\t */\n> -\tuint64_t sumG_;\n> -\t/**\n> -\t * \\brief Holds the sum of all sampled blue pixels\n> +\t * \\brief Sums of colour channels of all the sampled pixels\n> \t */\n> -\tuint64_t sumB_;\n> +\tRGB sum_;\n> \t/**\n> \t * \\brief Number of bins in the yHistogram\n> \t */\n> @@ -46,7 +40,7 @@ struct SwIspStats {\n> \t */\n> \tusing Histogram = std::array;\n> \t/**\n> -\t * \\brief A histogram of luminance values\n> +\t * \\brief A histogram of luminance values of all the sampled pixels\n> \t */\n> \tHistogram yHistogram;\n> };\n> diff --git a/src/ipa/simple/algorithms/awb.cpp b/src/ipa/simple/algorithms/awb.cpp\n> index 0080865aa..75e4ae4a4 100644\n> --- a/src/ipa/simple/algorithms/awb.cpp\n> +++ b/src/ipa/simple/algorithms/awb.cpp\n> @@ -1,6 +1,6 @@\n> /* SPDX-License-Identifier: LGPL-2.1-or-later */\n> /*\n> - * Copyright (C) 2024, Red Hat Inc.\n> + * Copyright (C) 2024-2026 Red Hat Inc.\n> *\n> * Auto white balance\n> */\n> @@ -73,9 +73,7 @@ void Awb::process(IPAContext &context,\n> \t\thistogram.begin(), histogram.end(), uint64_t(0));\n> \tconst uint64_t offset = blackLevel * nPixels;\n> \tconst uint64_t minValid = 1;\n> -\tconst uint64_t sumR = stats->sumR_ > offset / 4 ? stats->sumR_ - offset / 4 : minValid;\n> -\tconst uint64_t sumG = stats->sumG_ > offset / 2 ? stats->sumG_ - offset / 2 : minValid;\n> -\tconst uint64_t sumB = stats->sumB_ > offset / 4 ? stats->sumB_ - offset / 4 : minValid;\n> +\tconst RGB sum = (stats->sum_ - offset).max(minValid);\n> \n> \t/*\n> \t * Calculate red and blue gains for AWB.\n> @@ -83,9 +81,9 @@ void Awb::process(IPAContext &context,\n> \t */\n> \tauto &gains = context.activeState.awb.gains;\n> \tgains = { {\n> -\t\tsumR <= sumG / 4 ? 4.0f : static_cast(sumG) / sumR,\n> +\t\tsum.r() <= sum.g() / 4 ? 4.0f : static_cast(sum.g()) / sum.r(),\n> \t\t1.0,\n> -\t\tsumB <= sumG / 4 ? 4.0f : static_cast(sumG) / sumB,\n> +\t\tsum.b() <= sum.g() / 4 ? 4.0f : static_cast(sum.g()) / sum.b(),\n> \t} };\n> \n> \tRGB rgbGains{ { 1 / gains.r(), 1 / gains.g(), 1 / gains.b() } };\n> diff --git a/src/libcamera/software_isp/swstats_cpu.cpp b/src/libcamera/software_isp/swstats_cpu.cpp\n> index c931edb41..5c3011a7f 100644\n> --- a/src/libcamera/software_isp/swstats_cpu.cpp\n> +++ b/src/libcamera/software_isp/swstats_cpu.cpp\n> @@ -185,9 +185,9 @@ static constexpr unsigned int kBlueYMul = 29; /* 0.114 * 256 */\n> \tstats_.yHistogram[yVal * SwIspStats::kYHistogramSize / (256 * 256 * (div))]++;\n> \n> #define SWSTATS_FINISH_LINE_STATS() \\\n> -\tstats_.sumR_ += sumR; \\\n> -\tstats_.sumG_ += sumG; \\\n> -\tstats_.sumB_ += sumB;\n> +\tstats_.sum_.r() += sumR; \\\n> +\tstats_.sum_.g() += sumG; \\\n> +\tstats_.sum_.b() += sumB;\n> \n> void SwStatsCpu::statsBGGR8Line0(const uint8_t *src[])\n> {\n> @@ -332,9 +332,7 @@ void SwStatsCpu::startFrame(uint32_t frame)\n> \tif (window_.width == 0)\n> \t\tLOG(SwStatsCpu, Error) << \"Calling startFrame() without setWindow()\";\n> \n> -\tstats_.sumR_ = 0;\n> -\tstats_.sumB_ = 0;\n> -\tstats_.sumG_ = 0;\n> +\tstats_.sum_ = RGB({ 0, 0, 0 });\n> \tstats_.yHistogram.fill(0);\n> }\n>","headers":{"Return-Path":"","X-Original-To":"parsemail@patchwork.libcamera.org","Delivered-To":"parsemail@patchwork.libcamera.org","Received":["from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id 0588DC3200\n\tfor ;\n\tTue, 27 Jan 2026 16:45:02 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 51BFE61FC8;\n\tTue, 27 Jan 2026 17:45:01 +0100 (CET)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id E2EE761FBF\n\tfor ;\n\tTue, 27 Jan 2026 17:44:59 +0100 (CET)","from pendragon.ideasonboard.com\n\t(2001-14ba-703d-e500--2a1.rev.dnainternet.fi\n\t[IPv6:2001:14ba:703d:e500::2a1])\n\tby perceval.ideasonboard.com (Postfix) with UTF8SMTPSA id 6C96D465;\n\tTue, 27 Jan 2026 17:44:23 +0100 (CET)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"ZCiY5re/\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1769532263;\n\tbh=qUOzKLlyBT4GTmFq0mHDUAHKnc+c8UJhW6AQ5ieNHjE=;\n\th=Date:From:To:Cc:Subject:References:In-Reply-To:From;\n\tb=ZCiY5re/5U/Bc31vWXngmBPku1mXrhxUUUyGMPXtf442Xn6kGmBzoFtPy9NmqTixA\n\tVpb+6X243rqjxywHbbcz3DRR2nUFdWPcVKXd7pg6NeFp0J0upGrgkDYWpgOIKX6bBn\n\tBWcWJPR+c74tiQZHz5HeoKZaV/inOV+9SUUk8J8Q=","Date":"Tue, 27 Jan 2026 18:44:58 +0200","From":"Laurent Pinchart ","To":"Milan Zamazal ","Cc":"libcamera-devel@lists.libcamera.org,\n\tRobert Mader ","Subject":"Re: [PATCH v2] libcamera: simple: Fix black level offsets in AWB","Message-ID":"<20260127164458.GB2512313@killaraus>","References":"<20260127162923.112675-1-mzamazal@redhat.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=utf-8","Content-Disposition":"inline","In-Reply-To":"<20260127162923.112675-1-mzamazal@redhat.com>","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "}},{"id":37976,"web_url":"https://patchwork.libcamera.org/comment/37976/","msgid":"<14b9d127-bd84-4823-813c-9149bf4054ba@collabora.com>","date":"2026-01-27T16:50:21","subject":"Re: [PATCH v2] libcamera: simple: Fix black level offsets in AWB","submitter":{"id":140,"url":"https://patchwork.libcamera.org/api/people/140/","name":"Robert Mader","email":"robert.mader@collabora.com"},"content":"On 27.01.26 17:29, Milan Zamazal wrote:\n> The black level offset subtracted in AWB is wrong. It assumes that the\n> stats contain sums of the individual colour pixels. But they actually\n> contain sums of the colour channels of larger \"superpixels\" consisting\n> of the individual colour pixels. Each of the RGB colour values and the\n> computed luminosity (a histogram entry) are added once to the stats per\n> such a superpixel. This means the offset computed from the black level\n> and the number of pixels should be used as it is, not divided.\n>\n> The patch fixes the subtracted offset. Since the evaluation is the same\n> for all the three colours now, the individual class variables are\n> replaced with a single RGB variable.\n>\n> Fixes: 4e13c6f55bd667 (\"Honor black level in AWB\")\n> Signed-off-by: Milan Zamazal\n\nReviewed-by: Robert Mader\n\nTested-by: Robert Mader\n\n> ---\n> .../internal/software_isp/swisp_stats.h | 16 +++++-----------\n> src/ipa/simple/algorithms/awb.cpp | 10 ++++------\n> src/libcamera/software_isp/swstats_cpu.cpp | 10 ++++------\n> 3 files changed, 13 insertions(+), 23 deletions(-)\n>\n> diff --git a/include/libcamera/internal/software_isp/swisp_stats.h b/include/libcamera/internal/software_isp/swisp_stats.h\n> index 3c9860185..d9d0d9be8 100644\n> --- a/include/libcamera/internal/software_isp/swisp_stats.h\n> +++ b/include/libcamera/internal/software_isp/swisp_stats.h\n> @@ -10,6 +10,8 @@\n> #include \n> #include \n> \n> +#include \"libcamera/internal/vector.h\"\n> +\n> namespace libcamera {\n> \n> /**\n> @@ -26,17 +28,9 @@ struct SwIspStats {\n> \t */\n> \tbool valid;\n> \t/**\n> -\t * \\brief Holds the sum of all sampled red pixels\n> -\t */\n> -\tuint64_t sumR_;\n> -\t/**\n> -\t * \\brief Holds the sum of all sampled green pixels\n> -\t */\n> -\tuint64_t sumG_;\n> -\t/**\n> -\t * \\brief Holds the sum of all sampled blue pixels\n> +\t * \\brief Sums of colour channels of all the sampled pixels\n> \t */\n> -\tuint64_t sumB_;\n> +\tRGB sum_;\n> \t/**\n> \t * \\brief Number of bins in the yHistogram\n> \t */\n> @@ -46,7 +40,7 @@ struct SwIspStats {\n> \t */\n> \tusing Histogram = std::array;\n> \t/**\n> -\t * \\brief A histogram of luminance values\n> +\t * \\brief A histogram of luminance values of all the sampled pixels\n> \t */\n> \tHistogram yHistogram;\n> };\n> diff --git a/src/ipa/simple/algorithms/awb.cpp b/src/ipa/simple/algorithms/awb.cpp\n> index 0080865aa..75e4ae4a4 100644\n> --- a/src/ipa/simple/algorithms/awb.cpp\n> +++ b/src/ipa/simple/algorithms/awb.cpp\n> @@ -1,6 +1,6 @@\n> /* SPDX-License-Identifier: LGPL-2.1-or-later */\n> /*\n> - * Copyright (C) 2024, Red Hat Inc.\n> + * Copyright (C) 2024-2026 Red Hat Inc.\n> *\n> * Auto white balance\n> */\n> @@ -73,9 +73,7 @@ void Awb::process(IPAContext &context,\n> \t\thistogram.begin(), histogram.end(), uint64_t(0));\n> \tconst uint64_t offset = blackLevel * nPixels;\n> \tconst uint64_t minValid = 1;\n> -\tconst uint64_t sumR = stats->sumR_ > offset / 4 ? stats->sumR_ - offset / 4 : minValid;\n> -\tconst uint64_t sumG = stats->sumG_ > offset / 2 ? stats->sumG_ - offset / 2 : minValid;\n> -\tconst uint64_t sumB = stats->sumB_ > offset / 4 ? stats->sumB_ - offset / 4 : minValid;\n> +\tconst RGB sum = (stats->sum_ - offset).max(minValid);\n> \n> \t/*\n> \t * Calculate red and blue gains for AWB.\n> @@ -83,9 +81,9 @@ void Awb::process(IPAContext &context,\n> \t */\n> \tauto &gains = context.activeState.awb.gains;\n> \tgains = { {\n> -\t\tsumR <= sumG / 4 ? 4.0f : static_cast(sumG) / sumR,\n> +\t\tsum.r() <= sum.g() / 4 ? 4.0f : static_cast(sum.g()) / sum.r(),\n> \t\t1.0,\n> -\t\tsumB <= sumG / 4 ? 4.0f : static_cast(sumG) / sumB,\n> +\t\tsum.b() <= sum.g() / 4 ? 4.0f : static_cast(sum.g()) / sum.b(),\n> \t} };\n> \n> \tRGB rgbGains{ { 1 / gains.r(), 1 / gains.g(), 1 / gains.b() } };\n> diff --git a/src/libcamera/software_isp/swstats_cpu.cpp b/src/libcamera/software_isp/swstats_cpu.cpp\n> index c931edb41..5c3011a7f 100644\n> --- a/src/libcamera/software_isp/swstats_cpu.cpp\n> +++ b/src/libcamera/software_isp/swstats_cpu.cpp\n> @@ -185,9 +185,9 @@ static constexpr unsigned int kBlueYMul = 29; /* 0.114 * 256 */\n> \tstats_.yHistogram[yVal * SwIspStats::kYHistogramSize / (256 * 256 * (div))]++;\n> \n> #define SWSTATS_FINISH_LINE_STATS() \\\n> -\tstats_.sumR_ += sumR; \\\n> -\tstats_.sumG_ += sumG; \\\n> -\tstats_.sumB_ += sumB;\n> +\tstats_.sum_.r() += sumR; \\\n> +\tstats_.sum_.g() += sumG; \\\n> +\tstats_.sum_.b() += sumB;\n> \n> void SwStatsCpu::statsBGGR8Line0(const uint8_t *src[])\n> {\n> @@ -332,9 +332,7 @@ void SwStatsCpu::startFrame(uint32_t frame)\n> \tif (window_.width == 0)\n> \t\tLOG(SwStatsCpu, Error) << \"Calling startFrame() without setWindow()\";\n> \n> -\tstats_.sumR_ = 0;\n> -\tstats_.sumB_ = 0;\n> -\tstats_.sumG_ = 0;\n> +\tstats_.sum_ = RGB({ 0, 0, 0 });\n> \tstats_.yHistogram.fill(0);\n> }\n>","headers":{"Return-Path":"","X-Original-To":"parsemail@patchwork.libcamera.org","Delivered-To":"parsemail@patchwork.libcamera.org","Received":["from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id F377BC3220\n\tfor ;\n\tTue, 27 Jan 2026 16:50:32 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id E514061FC9;\n\tTue, 27 Jan 2026 17:50:31 +0100 (CET)","from sender4-pp-f112.zoho.com (sender4-pp-f112.zoho.com\n\t[136.143.188.112])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id E3C0161FC4\n\tfor ;\n\tTue, 27 Jan 2026 17:50:29 +0100 (CET)","by mx.zohomail.com with SMTPS id 1769532625447783.5075588525947;\n\tTue, 27 Jan 2026 08:50:25 -0800 (PST)"],"Authentication-Results":"lancelot.ideasonboard.com; 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a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1769532627;\n\ts=zohomail; d=collabora.com; i=robert.mader@collabora.com;\n\th=Content-Type:Message-ID:Date:Date:MIME-Version:Subject:Subject:To:To:Cc:Cc:References:From:From:In-Reply-To:Message-Id:Reply-To;\n\tbh=CfVMWX847b7seE12X5k2yengTFNgtZnKRr2JKgnqwsE=;\n\tb=NO4iG9pFKpf0GT0KXXKvzFbt6weVMTtIZdGEE9bQUnlGNqL5Qx1kt7Nn+nN50rHW\n\trs5kTYzT5XlA94LmuZi4h7lmbyif0N8VZBNyP3Z0Ig244ZfQk0DzYXACK+MggisfPP7\n\tOvlkqlfiI+v2YsEmi1pb9BeVrtvDLZq9DVD0rxJ8=","Content-Type":"multipart/alternative;\n\tboundary=\"------------78FINnhxvqLrxovQixhUIZym\"","Message-ID":"<14b9d127-bd84-4823-813c-9149bf4054ba@collabora.com>","Date":"Tue, 27 Jan 2026 17:50:21 +0100","MIME-Version":"1.0","User-Agent":"Mozilla Thunderbird","Subject":"Re: [PATCH v2] libcamera: simple: Fix black level offsets in AWB","To":"Milan Zamazal , libcamera-devel@lists.libcamera.org","Cc":"Laurent Pinchart ","References":"<20260127162923.112675-1-mzamazal@redhat.com>","Content-Language":"en-US, de-DE","From":"Robert Mader ","In-Reply-To":"<20260127162923.112675-1-mzamazal@redhat.com>","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "}},{"id":37977,"web_url":"https://patchwork.libcamera.org/comment/37977/","msgid":"","date":"2026-01-27T17:09:43","subject":"Re: [PATCH v2] libcamera: simple: Fix black level offsets in AWB","submitter":{"id":216,"url":"https://patchwork.libcamera.org/api/people/216/","name":"Barnabás Pőcze","email":"barnabas.pocze@ideasonboard.com"},"content":"Hi\n\n2026. 01. 27. 17:29 keltezéssel, Milan Zamazal írta:\n> The black level offset subtracted in AWB is wrong. It assumes that the\n> stats contain sums of the individual colour pixels. But they actually\n> contain sums of the colour channels of larger \"superpixels\" consisting\n> of the individual colour pixels. Each of the RGB colour values and the\n> computed luminosity (a histogram entry) are added once to the stats per\n> such a superpixel. This means the offset computed from the black level\n> and the number of pixels should be used as it is, not divided.\n> \n> The patch fixes the subtracted offset. Since the evaluation is the same\n> for all the three colours now, the individual class variables are\n> replaced with a single RGB variable.\n> \n> Fixes: 4e13c6f55bd667 (\"Honor black level in AWB\")\n> Signed-off-by: Milan Zamazal \n> ---\n> .../internal/software_isp/swisp_stats.h | 16 +++++-----------\n> src/ipa/simple/algorithms/awb.cpp | 10 ++++------\n> src/libcamera/software_isp/swstats_cpu.cpp | 10 ++++------\n> 3 files changed, 13 insertions(+), 23 deletions(-)\n> \n> diff --git a/include/libcamera/internal/software_isp/swisp_stats.h b/include/libcamera/internal/software_isp/swisp_stats.h\n> index 3c9860185..d9d0d9be8 100644\n> --- a/include/libcamera/internal/software_isp/swisp_stats.h\n> +++ b/include/libcamera/internal/software_isp/swisp_stats.h\n> @@ -10,6 +10,8 @@\n> #include \n> #include \n> \n> +#include \"libcamera/internal/vector.h\"\n> +\n> namespace libcamera {\n> \n> /**\n> @@ -26,17 +28,9 @@ struct SwIspStats {\n> \t */\n> \tbool valid;\n> \t/**\n> -\t * \\brief Holds the sum of all sampled red pixels\n> -\t */\n> -\tuint64_t sumR_;\n> -\t/**\n> -\t * \\brief Holds the sum of all sampled green pixels\n> -\t */\n> -\tuint64_t sumG_;\n> -\t/**\n> -\t * \\brief Holds the sum of all sampled blue pixels\n> +\t * \\brief Sums of colour channels of all the sampled pixels\n> \t */\n> -\tuint64_t sumB_;\n> +\tRGB sum_;\n> \t/**\n> \t * \\brief Number of bins in the yHistogram\n> \t */\n> @@ -46,7 +40,7 @@ struct SwIspStats {\n> \t */\n> \tusing Histogram = std::array;\n> \t/**\n> -\t * \\brief A histogram of luminance values\n> +\t * \\brief A histogram of luminance values of all the sampled pixels\n> \t */\n> \tHistogram yHistogram;\n> };\n> diff --git a/src/ipa/simple/algorithms/awb.cpp b/src/ipa/simple/algorithms/awb.cpp\n> index 0080865aa..75e4ae4a4 100644\n> --- a/src/ipa/simple/algorithms/awb.cpp\n> +++ b/src/ipa/simple/algorithms/awb.cpp\n> @@ -1,6 +1,6 @@\n> /* SPDX-License-Identifier: LGPL-2.1-or-later */\n> /*\n> - * Copyright (C) 2024, Red Hat Inc.\n> + * Copyright (C) 2024-2026 Red Hat Inc.\n> *\n> * Auto white balance\n> */\n> @@ -73,9 +73,7 @@ void Awb::process(IPAContext &context,\n> \t\thistogram.begin(), histogram.end(), uint64_t(0));\n> \tconst uint64_t offset = blackLevel * nPixels;\n> \tconst uint64_t minValid = 1;\n> -\tconst uint64_t sumR = stats->sumR_ > offset / 4 ? stats->sumR_ - offset / 4 : minValid;\n> -\tconst uint64_t sumG = stats->sumG_ > offset / 2 ? stats->sumG_ - offset / 2 : minValid;\n> -\tconst uint64_t sumB = stats->sumB_ > offset / 4 ? stats->sumB_ - offset / 4 : minValid;\n> +\tconst RGB sum = (stats->sum_ - offset).max(minValid);\n\nWhat happens if the subtraction wraps around? Previously that was avoided\nby the removed check. Or is wraparound actually impossible now?\n\n\n> [...]","headers":{"Return-Path":"","X-Original-To":"parsemail@patchwork.libcamera.org","Delivered-To":"parsemail@patchwork.libcamera.org","Received":["from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id 88A37C3200\n\tfor ;\n\tTue, 27 Jan 2026 17:09:51 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 90CDC61FCF;\n\tTue, 27 Jan 2026 18:09:50 +0100 (CET)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id D321C61FBF\n\tfor ;\n\tTue, 27 Jan 2026 18:09:48 +0100 (CET)","from [192.168.33.37] (185.221.142.123.nat.pool.zt.hu\n\t[185.221.142.123])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 9AD5778E;\n\tTue, 27 Jan 2026 18:09:11 +0100 (CET)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"X5cvvi/g\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1769533752;\n\tbh=ghbNc+VJf6w/rFhAgVAvP7ZLOvDgw8slCSUtyGaxv3M=;\n\th=Date:Subject:To:Cc:References:From:In-Reply-To:From;\n\tb=X5cvvi/gVSF3cjwBCn7/YtTba4UgYUGrBNMine3nnRlTWkNlUZgHAEqTE5daC8DGy\n\tTgUHk8gzZ9bnNO+x013uUST+wkk8hEnEEeW7GTXWDgJuTb/eh5W7hfJdCf2hiYosV5\n\tPaQ5if3NQwJEiQAPDP6D/BU+B7+TYjIkp5wn06Mk=","Message-ID":"","Date":"Tue, 27 Jan 2026 18:09:43 +0100","MIME-Version":"1.0","User-Agent":"Mozilla Thunderbird","Subject":"Re: [PATCH v2] libcamera: simple: Fix black level offsets in AWB","To":"Milan Zamazal , libcamera-devel@lists.libcamera.org","Cc":"Laurent Pinchart ,\n\tRobert Mader ","References":"<20260127162923.112675-1-mzamazal@redhat.com>","From":"=?utf-8?q?Barnab=C3=A1s_P=C5=91cze?= ","Content-Language":"en-US, hu-HU","In-Reply-To":"<20260127162923.112675-1-mzamazal@redhat.com>","Content-Type":"text/plain; charset=UTF-8; format=flowed","Content-Transfer-Encoding":"8bit","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "}},{"id":37979,"web_url":"https://patchwork.libcamera.org/comment/37979/","msgid":"<85jyx3t1g5.fsf@mzamazal-thinkpadp1gen7.tpbc.csb>","date":"2026-01-27T17:22:50","subject":"Re: [PATCH v2] libcamera: simple: Fix black level offsets in AWB","submitter":{"id":177,"url":"https://patchwork.libcamera.org/api/people/177/","name":"Milan Zamazal","email":"mzamazal@redhat.com"},"content":"Barnabás Pőcze writes:\n\n> Hi\n>\n> 2026. 01. 27. 17:29 keltezéssel, Milan Zamazal írta:\n>> The black level offset subtracted in AWB is wrong. It assumes that the\n>> stats contain sums of the individual colour pixels. But they actually\n>> contain sums of the colour channels of larger \"superpixels\" consisting\n>> of the individual colour pixels. Each of the RGB colour values and the\n>> computed luminosity (a histogram entry) are added once to the stats per\n>> such a superpixel. This means the offset computed from the black level\n>> and the number of pixels should be used as it is, not divided.\n>> The patch fixes the subtracted offset. Since the evaluation is the same\n>> for all the three colours now, the individual class variables are\n>> replaced with a single RGB variable.\n>> Fixes: 4e13c6f55bd667 (\"Honor black level in AWB\")\n>> Signed-off-by: Milan Zamazal \n>> ---\n>> .../internal/software_isp/swisp_stats.h | 16 +++++-----------\n>> src/ipa/simple/algorithms/awb.cpp | 10 ++++------\n>> src/libcamera/software_isp/swstats_cpu.cpp | 10 ++++------\n>> 3 files changed, 13 insertions(+), 23 deletions(-)\n>> diff --git a/include/libcamera/internal/software_isp/swisp_stats.h b/include/libcamera/internal/software_isp/swisp_stats.h\n>> index 3c9860185..d9d0d9be8 100644\n>> --- a/include/libcamera/internal/software_isp/swisp_stats.h\n>> +++ b/include/libcamera/internal/software_isp/swisp_stats.h\n>> @@ -10,6 +10,8 @@\n>> #include \n>> #include \n>> +#include \"libcamera/internal/vector.h\"\n>> +\n>> namespace libcamera {\n>> /**\n>> @@ -26,17 +28,9 @@ struct SwIspStats {\n>> \t */\n>> \tbool valid;\n>> \t/**\n>> -\t * \\brief Holds the sum of all sampled red pixels\n>> -\t */\n>> -\tuint64_t sumR_;\n>> -\t/**\n>> -\t * \\brief Holds the sum of all sampled green pixels\n>> -\t */\n>> -\tuint64_t sumG_;\n>> -\t/**\n>> -\t * \\brief Holds the sum of all sampled blue pixels\n>> +\t * \\brief Sums of colour channels of all the sampled pixels\n>> \t */\n>> -\tuint64_t sumB_;\n>> +\tRGB sum_;\n>> \t/**\n>> \t * \\brief Number of bins in the yHistogram\n>> \t */\n>> @@ -46,7 +40,7 @@ struct SwIspStats {\n>> \t */\n>> \tusing Histogram = std::array;\n>> \t/**\n>> -\t * \\brief A histogram of luminance values\n>> +\t * \\brief A histogram of luminance values of all the sampled pixels\n>> \t */\n>> \tHistogram yHistogram;\n>> };\n>> diff --git a/src/ipa/simple/algorithms/awb.cpp b/src/ipa/simple/algorithms/awb.cpp\n>> index 0080865aa..75e4ae4a4 100644\n>> --- a/src/ipa/simple/algorithms/awb.cpp\n>> +++ b/src/ipa/simple/algorithms/awb.cpp\n>> @@ -1,6 +1,6 @@\n>> /* SPDX-License-Identifier: LGPL-2.1-or-later */\n>> /*\n>> - * Copyright (C) 2024, Red Hat Inc.\n>> + * Copyright (C) 2024-2026 Red Hat Inc.\n>> *\n>> * Auto white balance\n>> */\n>> @@ -73,9 +73,7 @@ void Awb::process(IPAContext &context,\n>> \t\thistogram.begin(), histogram.end(), uint64_t(0));\n>> \tconst uint64_t offset = blackLevel * nPixels;\n>> \tconst uint64_t minValid = 1;\n>> -\tconst uint64_t sumR = stats->sumR_ > offset / 4 ? stats->sumR_ - offset / 4 : minValid;\n>> -\tconst uint64_t sumG = stats->sumG_ > offset / 2 ? stats->sumG_ - offset / 2 : minValid;\n>> -\tconst uint64_t sumB = stats->sumB_ > offset / 4 ? stats->sumB_ - offset / 4 : minValid;\n>> +\tconst RGB sum = (stats->sum_ - offset).max(minValid);\n>\n> What happens if the subtraction wraps around? Previously that was avoided\n> by the removed check. Or is wraparound actually impossible now?\n\nOops, I've forgotten about that trap again, thank you for the reminder.\nI'll fix it some way in v3.","headers":{"Return-Path":"","X-Original-To":"parsemail@patchwork.libcamera.org","Delivered-To":"parsemail@patchwork.libcamera.org","Received":["from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id 53181C3200\n\tfor ;\n\tTue, 27 Jan 2026 17:22:58 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 8DC2361FC8;\n\tTue, 27 Jan 2026 18:22:57 +0100 (CET)","from us-smtp-delivery-124.mimecast.com\n\t(us-smtp-delivery-124.mimecast.com [170.10.133.124])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 3837761FBF\n\tfor ;\n\tTue, 27 Jan 2026 18:22:56 +0100 (CET)","from mail-wm1-f70.google.com (mail-wm1-f70.google.com\n\t[209.85.128.70]) by relay.mimecast.com with ESMTP with STARTTLS\n\t(version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id\n\tus-mta-582-gauAPQcPN5m6xruXe_YHfg-1; Tue, 27 Jan 2026 12:22:53 -0500","by mail-wm1-f70.google.com with SMTP id\n\t5b1f17b1804b1-47edf8ba319so55131765e9.2\n\tfor ;\n\tTue, 27 Jan 2026 09:22:53 -0800 (PST)","from mzamazal-thinkpadp1gen7.tpbc.csb\n\t(ip-77-48-47-2.net.vodafone.cz. 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It assumes that the\n>>> stats contain sums of the individual colour pixels. But they actually\n>>> contain sums of the colour channels of larger \"superpixels\" consisting\n>>> of the individual colour pixels. Each of the RGB colour values and the\n>>> computed luminosity (a histogram entry) are added once to the stats per\n>>> such a superpixel. This means the offset computed from the black level\n>>> and the number of pixels should be used as it is, not divided.\n>>> The patch fixes the subtracted offset. Since the evaluation is the same\n>>> for all the three colours now, the individual class variables are\n>>> replaced with a single RGB variable.\n>>> Fixes: 4e13c6f55bd667 (\"Honor black level in AWB\")\n>>> Signed-off-by: Milan Zamazal \n>>> ---\n>>> .../internal/software_isp/swisp_stats.h | 16 +++++-----------\n>>> src/ipa/simple/algorithms/awb.cpp | 10 ++++------\n>>> src/libcamera/software_isp/swstats_cpu.cpp | 10 ++++------\n>>> 3 files changed, 13 insertions(+), 23 deletions(-)\n>>> diff --git a/include/libcamera/internal/software_isp/swisp_stats.h b/include/libcamera/internal/software_isp/swisp_stats.h\n>>> index 3c9860185..d9d0d9be8 100644\n>>> --- a/include/libcamera/internal/software_isp/swisp_stats.h\n>>> +++ b/include/libcamera/internal/software_isp/swisp_stats.h\n>>> @@ -10,6 +10,8 @@\n>>> #include \n>>> #include \n>>> +#include \"libcamera/internal/vector.h\"\n>>> +\n>>> namespace libcamera {\n>>> /**\n>>> @@ -26,17 +28,9 @@ struct SwIspStats {\n>>> \t */\n>>> \tbool valid;\n>>> \t/**\n>>> -\t * \\brief Holds the sum of all sampled red pixels\n>>> -\t */\n>>> -\tuint64_t sumR_;\n>>> -\t/**\n>>> -\t * \\brief Holds the sum of all sampled green pixels\n>>> -\t */\n>>> -\tuint64_t sumG_;\n>>> -\t/**\n>>> -\t * \\brief Holds the sum of all sampled blue pixels\n>>> +\t * \\brief Sums of colour channels of all the sampled pixels\n>>> \t */\n>>> -\tuint64_t sumB_;\n>>> +\tRGB sum_;\n>>> \t/**\n>>> \t * \\brief Number of bins in the yHistogram\n>>> \t */\n>>> @@ -46,7 +40,7 @@ struct SwIspStats {\n>>> \t */\n>>> \tusing Histogram = std::array;\n>>> \t/**\n>>> -\t * \\brief A histogram of luminance values\n>>> +\t * \\brief A histogram of luminance values of all the sampled pixels\n>>> \t */\n>>> \tHistogram yHistogram;\n>>> };\n>>> diff --git a/src/ipa/simple/algorithms/awb.cpp b/src/ipa/simple/algorithms/awb.cpp\n>>> index 0080865aa..75e4ae4a4 100644\n>>> --- a/src/ipa/simple/algorithms/awb.cpp\n>>> +++ b/src/ipa/simple/algorithms/awb.cpp\n>>> @@ -1,6 +1,6 @@\n>>> /* SPDX-License-Identifier: LGPL-2.1-or-later */\n>>> /*\n>>> - * Copyright (C) 2024, Red Hat Inc.\n>>> + * Copyright (C) 2024-2026 Red Hat Inc.\n>>> *\n>>> * Auto white balance\n>>> */\n>>> @@ -73,9 +73,7 @@ void Awb::process(IPAContext &context,\n>>> \t\thistogram.begin(), histogram.end(), uint64_t(0));\n>>> \tconst uint64_t offset = blackLevel * nPixels;\n>>> \tconst uint64_t minValid = 1;\n>>> -\tconst uint64_t sumR = stats->sumR_ > offset / 4 ? stats->sumR_ - offset / 4 : minValid;\n>>> -\tconst uint64_t sumG = stats->sumG_ > offset / 2 ? stats->sumG_ - offset / 2 : minValid;\n>>> -\tconst uint64_t sumB = stats->sumB_ > offset / 4 ? stats->sumB_ - offset / 4 : minValid;\n>>> +\tconst RGB sum = (stats->sum_ - offset).max(minValid);\n>>\n>> What happens if the subtraction wraps around? Previously that was avoided\n>> by the removed check. Or is wraparound actually impossible now?\n> \n> Oops, I've forgotten about that trap again, thank you for the reminder.\n> I'll fix it some way in v3.\n> \n\nMaybe\n\n const RGB sum = stats->sum_.max(offset + minValid) - offset;\n\n?","headers":{"Return-Path":"","X-Original-To":"parsemail@patchwork.libcamera.org","Delivered-To":"parsemail@patchwork.libcamera.org","Received":["from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id 0342FC3220\n\tfor ;\n\tTue, 27 Jan 2026 18:59:14 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id EBDDC61FC8;\n\tTue, 27 Jan 2026 19:59:13 +0100 (CET)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 328FB61FBF\n\tfor ;\n\tTue, 27 Jan 2026 19:59:12 +0100 (CET)","from [192.168.33.37] (185.221.142.123.nat.pool.zt.hu\n\t[185.221.142.123])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 4CC9EE70;\n\tTue, 27 Jan 2026 19:58:34 +0100 (CET)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"agpRFwte\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1769540315;\n\tbh=8rsTJlT9obwfgZ04Ss+8R9gOd1EyGUAkpPDOk3KPI/k=;\n\th=Date:Subject:To:Cc:References:From:In-Reply-To:From;\n\tb=agpRFwte5skASIgYjAy4Ag2FGAbXWuISPQeGrMqVIURejzgZiUHYWvt+WKvZbpGhU\n\tOqJmRjcSwqzaf+2DiTtt7VZfMFadqjTzUNr1QT68Br4hqQBptnlAXkyTgMl7RD03RW\n\tfMMc1xoEG4F2BlKqKWfmu13HQyM1BDi5zl3LOEhg=","Message-ID":"<95779c5e-2b21-4416-9c97-ac4a297c0e59@ideasonboard.com>","Date":"Tue, 27 Jan 2026 19:59:05 +0100","MIME-Version":"1.0","User-Agent":"Mozilla Thunderbird","Subject":"Re: [PATCH v2] libcamera: simple: Fix black level offsets in AWB","To":"Milan Zamazal ","Cc":"libcamera-devel@lists.libcamera.org,\n\tLaurent Pinchart ,\n\tRobert Mader ","References":"<20260127162923.112675-1-mzamazal@redhat.com>\n\t\n\t<85jyx3t1g5.fsf@mzamazal-thinkpadp1gen7.tpbc.csb>","From":"=?utf-8?q?Barnab=C3=A1s_P=C5=91cze?= ","Content-Language":"en-US, hu-HU","In-Reply-To":"<85jyx3t1g5.fsf@mzamazal-thinkpadp1gen7.tpbc.csb>","Content-Type":"text/plain; charset=UTF-8; format=flowed","Content-Transfer-Encoding":"8bit","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "}},{"id":37981,"web_url":"https://patchwork.libcamera.org/comment/37981/","msgid":"<85ecnau6jj.fsf@mzamazal-thinkpadp1gen7.tpbc.csb>","date":"2026-01-27T20:47:28","subject":"Re: [PATCH v2] libcamera: simple: Fix black level offsets in AWB","submitter":{"id":177,"url":"https://patchwork.libcamera.org/api/people/177/","name":"Milan Zamazal","email":"mzamazal@redhat.com"},"content":"Barnabás Pőcze writes:\n\n> 2026. 01. 27. 18:22 keltezéssel, Milan Zamazal írta:\n>> Barnabás Pőcze writes:\n>> \n>>> Hi\n>>>\n>>> 2026. 01. 27. 17:29 keltezéssel, Milan Zamazal írta:\n>>>> The black level offset subtracted in AWB is wrong. It assumes that the\n>>>> stats contain sums of the individual colour pixels. But they actually\n>>>> contain sums of the colour channels of larger \"superpixels\" consisting\n>>>> of the individual colour pixels. Each of the RGB colour values and the\n>>>> computed luminosity (a histogram entry) are added once to the stats per\n>>>> such a superpixel. This means the offset computed from the black level\n>>>> and the number of pixels should be used as it is, not divided.\n>>>> The patch fixes the subtracted offset. Since the evaluation is the same\n>>>> for all the three colours now, the individual class variables are\n>>>> replaced with a single RGB variable.\n>>>> Fixes: 4e13c6f55bd667 (\"Honor black level in AWB\")\n>>>> Signed-off-by: Milan Zamazal \n>>>> ---\n>>>> .../internal/software_isp/swisp_stats.h | 16 +++++-----------\n>>>> src/ipa/simple/algorithms/awb.cpp | 10 ++++------\n>>>> src/libcamera/software_isp/swstats_cpu.cpp | 10 ++++------\n>>>> 3 files changed, 13 insertions(+), 23 deletions(-)\n>>>> diff --git a/include/libcamera/internal/software_isp/swisp_stats.h b/include/libcamera/internal/software_isp/swisp_stats.h\n>>>> index 3c9860185..d9d0d9be8 100644\n>>>> --- a/include/libcamera/internal/software_isp/swisp_stats.h\n>>>> +++ b/include/libcamera/internal/software_isp/swisp_stats.h\n>>>> @@ -10,6 +10,8 @@\n>>>> #include \n>>>> #include \n>>>> +#include \"libcamera/internal/vector.h\"\n>>>> +\n>>>> namespace libcamera {\n>>>> /**\n>>>> @@ -26,17 +28,9 @@ struct SwIspStats {\n>>>> \t */\n>>>> \tbool valid;\n>>>> \t/**\n>>>> -\t * \\brief Holds the sum of all sampled red pixels\n>>>> -\t */\n>>>> -\tuint64_t sumR_;\n>>>> -\t/**\n>>>> -\t * \\brief Holds the sum of all sampled green pixels\n>>>> -\t */\n>>>> -\tuint64_t sumG_;\n>>>> -\t/**\n>>>> -\t * \\brief Holds the sum of all sampled blue pixels\n>>>> +\t * \\brief Sums of colour channels of all the sampled pixels\n>>>> \t */\n>>>> -\tuint64_t sumB_;\n>>>> +\tRGB sum_;\n>>>> \t/**\n>>>> \t * \\brief Number of bins in the yHistogram\n>>>> \t */\n>>>> @@ -46,7 +40,7 @@ struct SwIspStats {\n>>>> \t */\n>>>> \tusing Histogram = std::array;\n>>>> \t/**\n>>>> -\t * \\brief A histogram of luminance values\n>>>> +\t * \\brief A histogram of luminance values of all the sampled pixels\n>>>> \t */\n>>>> \tHistogram yHistogram;\n>>>> };\n>>>> diff --git a/src/ipa/simple/algorithms/awb.cpp b/src/ipa/simple/algorithms/awb.cpp\n>>>> index 0080865aa..75e4ae4a4 100644\n>>>> --- a/src/ipa/simple/algorithms/awb.cpp\n>>>> +++ b/src/ipa/simple/algorithms/awb.cpp\n>>>> @@ -1,6 +1,6 @@\n>>>> /* SPDX-License-Identifier: LGPL-2.1-or-later */\n>>>> /*\n>>>> - * Copyright (C) 2024, Red Hat Inc.\n>>>> + * Copyright (C) 2024-2026 Red Hat Inc.\n>>>> *\n>>>> * Auto white balance\n>>>> */\n>>>> @@ -73,9 +73,7 @@ void Awb::process(IPAContext &context,\n>>>> \t\thistogram.begin(), histogram.end(), uint64_t(0));\n>>>> \tconst uint64_t offset = blackLevel * nPixels;\n>>>> \tconst uint64_t minValid = 1;\n>>>> -\tconst uint64_t sumR = stats->sumR_ > offset / 4 ? stats->sumR_ - offset / 4 : minValid;\n>>>> -\tconst uint64_t sumG = stats->sumG_ > offset / 2 ? stats->sumG_ - offset / 2 : minValid;\n>>>> -\tconst uint64_t sumB = stats->sumB_ > offset / 4 ? stats->sumB_ - offset / 4 : minValid;\n>>>> +\tconst RGB sum = (stats->sum_ - offset).max(minValid);\n>>>\n>>> What happens if the subtraction wraps around? Previously that was avoided\n>>> by the removed check. Or is wraparound actually impossible now?\n>> Oops, I've forgotten about that trap again, thank you for the reminder.\n>> I'll fix it some way in v3.\n>> \n>\n> Maybe\n>\n> const RGB sum = stats->sum_.max(offset + minValid) - offset;\n>\n> ?\n\nNice, thanks. Applied in v3 + added a source comment there for\nclarification and not to repeat the mistake again.","headers":{"Return-Path":"","X-Original-To":"parsemail@patchwork.libcamera.org","Delivered-To":"parsemail@patchwork.libcamera.org","Received":["from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id CFB31C3200\n\tfor ;\n\tTue, 27 Jan 2026 20:47:36 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 82BC761FCB;\n\tTue, 27 Jan 2026 21:47:36 +0100 (CET)","from us-smtp-delivery-124.mimecast.com\n\t(us-smtp-delivery-124.mimecast.com [170.10.133.124])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 2066761FBF\n\tfor ;\n\tTue, 27 Jan 2026 21:47:35 +0100 (CET)","from mail-wr1-f72.google.com (mail-wr1-f72.google.com\n\t[209.85.221.72]) by relay.mimecast.com with ESMTP with STARTTLS\n\t(version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id\n\tus-mta-218-GJfJfForMa-AClP2qFz2qA-1; Tue, 27 Jan 2026 15:47:32 -0500","by mail-wr1-f72.google.com with SMTP id\n\tffacd0b85a97d-4358f90fe8dso305864f8f.0\n\tfor ;\n\tTue, 27 Jan 2026 12:47:32 -0800 (PST)","from mzamazal-thinkpadp1gen7.tpbc.csb\n\t(ip-77-48-47-2.net.vodafone.cz. 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