[{"id":39201,"web_url":"https://patchwork.libcamera.org/comment/39201/","msgid":"<178199683048.2732614.17411488518816313683@ping.linuxembedded.co.uk>","date":"2026-06-20T23:07:10","subject":"Re: [PATCH 5/7] libcamera: software_isp: Fix black level handling in\n\tCPU ISP","submitter":{"id":4,"url":"https://patchwork.libcamera.org/api/people/4/","name":"Kieran Bingham","email":"kieran.bingham@ideasonboard.com"},"content":"Quoting Kieran Bingham (2026-06-21 00:00:32)\n> From: Milan Zamazal \n> \n> The black level handling in CPU ISP has two flaws:\n> \n> - The black level is applied after white balance rather than before.\n> \n> - It doesn't handle black levels with different values for individual\n> colour channels.\n> \n> The flaws are in both CCM and non-CCM cases. The wrong black level and\n> white balance application order is well visible when the white balance\n> gains are significantly different from 1.0. Then the output differs\n> significantly from GPU ISP output, which uses the correct order.\n> \n> This patch changes the computations of the lookup tables in a way that\n> fixes both the problems.\n> \n> [Kieran: Fix indexing from Milans' suggestion, use new clamp]\n> [Kieran: Use enumerate, and div updates from Laurent's suggestion]\n> Signed-off-by: Milan Zamazal \n\nAnd this of course\n\nSigned-off-by: Kieran Bingham ","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 3950BC3303\n\tfor ;\n\tSat, 20 Jun 2026 23:07:16 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 21D33656E5;\n\tSun, 21 Jun 2026 01:07:15 +0200 (CEST)","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 AAF78656DE\n\tfor ;\n\tSun, 21 Jun 2026 01:07:13 +0200 (CEST)","from monstersaurus.ideasonboard.com\n\t(cpc89244-aztw30-2-0-cust6594.18-1.cable.virginm.net [86.31.185.195])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id CC7C1B8B;\n\tSun, 21 Jun 2026 01:06:36 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"ahByVllw\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1781996796;\n\tbh=mx6JpuZFimW9UJmeWedPFmpOQixEWMwHKajudmQ8Wb8=;\n\th=In-Reply-To:References:Subject:From:Cc:To:Date:From;\n\tb=ahByVllwVfY9ekUBpVn9Dv9s4f0+G+DTaIkEqHXKRbRnB0uEzueU+S5n/abwKv4zF\n\t4IMSUYdmPfk3yODqfLKhIV+iWwRksYUD3d0J/X3B1Id2Y1cu4kL6mC4CzXuZ4rABl7\n\tpQ7iYbTxdKD9+oYQ6jH4UvWkrnahQyzFfr6DXvMQ=","Content-Type":"text/plain; charset=\"utf-8\"","MIME-Version":"1.0","Content-Transfer-Encoding":"quoted-printable","In-Reply-To":"<20260621-kbingham-awb-saturation-v1-5-b91ea59c6cfb@ideasonboard.com>","References":"<20260621-kbingham-awb-saturation-v1-0-b91ea59c6cfb@ideasonboard.com>\n\t<20260621-kbingham-awb-saturation-v1-5-b91ea59c6cfb@ideasonboard.com>","Subject":"Re: [PATCH 5/7] libcamera: software_isp: Fix black level handling in\n\tCPU ISP","From":"Kieran Bingham ","Cc":"Milan Zamazal ","To":"libcamera-devel@lists.libcamera.org","Date":"Sun, 21 Jun 2026 00:07:10 +0100","Message-ID":"<178199683048.2732614.17411488518816313683@ping.linuxembedded.co.uk>","User-Agent":"alot/0.9.1","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":39285,"web_url":"https://patchwork.libcamera.org/comment/39285/","msgid":"<85qzly8hxf.fsf@mzamazal-thinkpadp1gen7.tpbc.csb>","date":"2026-06-22T19:59:56","subject":"Re: [PATCH 5/7] libcamera: software_isp: Fix black level handling\n\tin CPU ISP","submitter":{"id":177,"url":"https://patchwork.libcamera.org/api/people/177/","name":"Milan Zamazal","email":"mzamazal@redhat.com"},"content":"Hi Kieran,\n\nthank you for the update.\n\nKieran Bingham writes:\n\n> From: Milan Zamazal \n>\n> The black level handling in CPU ISP has two flaws:\n>\n> - The black level is applied after white balance rather than before.\n>\n> - It doesn't handle black levels with different values for individual\n> colour channels.\n>\n> The flaws are in both CCM and non-CCM cases. The wrong black level and\n> white balance application order is well visible when the white balance\n> gains are significantly different from 1.0. Then the output differs\n> significantly from GPU ISP output, which uses the correct order.\n>\n> This patch changes the computations of the lookup tables in a way that\n> fixes both the problems.\n>\n> [Kieran: Fix indexing from Milans' suggestion, use new clamp]\n> [Kieran: Use enumerate, and div updates from Laurent's suggestion]\n\nAs for Kieran's changes:\n\nReviewed-by: Milan Zamazal \n\n> Signed-off-by: Milan Zamazal \n> ---\n> src/libcamera/software_isp/debayer_cpu.cpp | 60 ++++++++++++++----------------\n> 1 file changed, 28 insertions(+), 32 deletions(-)\n>\n> diff --git a/src/libcamera/software_isp/debayer_cpu.cpp b/src/libcamera/software_isp/debayer_cpu.cpp\n> index d2596d32bbcdeaaab2e2c287e3f01ae22c442884..9d6a08b3333f988570cb5d3f7cea4c117f7c2530 100644\n> --- a/src/libcamera/software_isp/debayer_cpu.cpp\n> +++ b/src/libcamera/software_isp/debayer_cpu.cpp\n> @@ -979,32 +979,20 @@ void DebayerCpuThread::process4(uint32_t frame, const uint8_t *src, uint8_t *dst\n> \n> void DebayerCpu::updateGammaTable(const DebayerParams ¶ms)\n> {\n> -\tconst RGB blackLevel = params.blackLevel;\n> -\t/* Take let's say the green channel black level */\n> -\tconst unsigned int blackIndex = blackLevel[1] * gammaTable_.size();\n> \tconst float gamma = params.gamma;\n> \tconst float contrastExp = params.contrastExp;\n> \n> -\tconst float divisor = gammaTable_.size() - blackIndex - 1.0;\n> -\tfor (unsigned int i = blackIndex; i < gammaTable_.size(); i++) {\n> -\t\tfloat normalized = (i - blackIndex) / divisor;\n> +\tconst float divisor = gammaTable_.size() - 1.0;\n> +\tfor (auto [i, value] : utils::enumerate(gammaTable_)) {\n> +\t\tfloat normalized = i / divisor;\n> \t\t/* Convert 0..2 to 0..infinity; avoid actual inifinity at tan(pi/2) */\n> \t\t/* Apply simple S-curve */\n> \t\tif (normalized < 0.5)\n> \t\t\tnormalized = 0.5 * std::pow(normalized / 0.5, contrastExp);\n> \t\telse\n> \t\t\tnormalized = 1.0 - 0.5 * std::pow((1.0 - normalized) / 0.5, contrastExp);\n> -\t\tgammaTable_[i] = UINT8_MAX *\n> -\t\t\t\t std::pow(normalized, gamma);\n> +\t\tvalue = UINT8_MAX * std::pow(normalized, gamma);\n> \t}\n> -\t/*\n> -\t * Due to CCM operations, the table lookup may reach indices below the black\n> -\t * level. Let's set the table values below black level to the minimum\n> -\t * non-black value to prevent problems when the minimum value is\n> -\t * significantly non-zero (for example, when the image should be all grey).\n> -\t */\n> -\tstd::fill(gammaTable_.begin(), gammaTable_.begin() + blackIndex,\n> -\t\t gammaTable_[blackIndex]);\n> }\n> \n> void DebayerCpu::updateLookupTables(const DebayerParams ¶ms)\n> @@ -1016,11 +1004,15 @@ void DebayerCpu::updateLookupTables(const DebayerParams ¶ms)\n> \tif (gammaUpdateNeeded)\n> \t\tupdateGammaTable(params);\n> \n> +\t/* Processing order: black level -> gains -> gamma */\n> \tauto matrixChanged = [](const Matrix &m1, const Matrix &m2) -> bool {\n> \t\treturn !std::equal(m1.data().begin(), m1.data().end(), m2.data().begin());\n> \t};\n> \tconst unsigned int gammaTableSize = gammaTable_.size();\n> -\tconst double div = static_cast(kRGBLookupSize) / gammaTableSize;\n> +\n> +\tconst RGB blackIndex = params.blackLevel * kRGBLookupSize;\n> +\tconst RGB div = (RGB(kRGBLookupSize) - blackIndex).max(1.0);\n> +\n> \tif (ccmEnabled_) {\n> \t\tif (gammaUpdateNeeded ||\n> \t\t matrixChanged(params.combinedMatrix, params_.combinedMatrix)) {\n> @@ -1030,17 +1022,19 @@ void DebayerCpu::updateLookupTables(const DebayerParams ¶ms)\n> \t\t\tconst unsigned int redIndex = swapRedBlueGains_ ? 2 : 0;\n> \t\t\tconst unsigned int greenIndex = 1;\n> \t\t\tconst unsigned int blueIndex = swapRedBlueGains_ ? 0 : 2;\n> +\n> \t\t\tfor (unsigned int i = 0; i < kRGBLookupSize; i++) {\n> -\t\t\t\tred[i].r = std::round(i * params.combinedMatrix[redIndex][0]);\n> -\t\t\t\tred[i].g = std::round(i * params.combinedMatrix[greenIndex][0]);\n> -\t\t\t\tred[i].b = std::round(i * params.combinedMatrix[blueIndex][0]);\n> -\t\t\t\tgreen[i].r = std::round(i * params.combinedMatrix[redIndex][1]);\n> -\t\t\t\tgreen[i].g = std::round(i * params.combinedMatrix[greenIndex][1]);\n> -\t\t\t\tgreen[i].b = std::round(i * params.combinedMatrix[blueIndex][1]);\n> -\t\t\t\tblue[i].r = std::round(i * params.combinedMatrix[redIndex][2]);\n> -\t\t\t\tblue[i].g = std::round(i * params.combinedMatrix[greenIndex][2]);\n> -\t\t\t\tblue[i].b = std::round(i * params.combinedMatrix[blueIndex][2]);\n> -\t\t\t\tgammaLut_[i] = gammaTable_[i / div];\n> +\t\t\t\tconst RGB rgb = ((RGB(i) - blackIndex) * kRGBLookupSize / div).max(0.0);\n> +\t\t\t\tred[i].r = std::round(rgb.r() * params.combinedMatrix[redIndex][0]);\n> +\t\t\t\tred[i].g = std::round(rgb.r() * params.combinedMatrix[greenIndex][0]);\n> +\t\t\t\tred[i].b = std::round(rgb.r() * params.combinedMatrix[blueIndex][0]);\n> +\t\t\t\tgreen[i].r = std::round(rgb.g() * params.combinedMatrix[redIndex][1]);\n> +\t\t\t\tgreen[i].g = std::round(rgb.g() * params.combinedMatrix[greenIndex][1]);\n> +\t\t\t\tgreen[i].b = std::round(rgb.g() * params.combinedMatrix[blueIndex][1]);\n> +\t\t\t\tblue[i].r = std::round(rgb.b() * params.combinedMatrix[redIndex][2]);\n> +\t\t\t\tblue[i].g = std::round(rgb.b() * params.combinedMatrix[greenIndex][2]);\n> +\t\t\t\tblue[i].b = std::round(rgb.b() * params.combinedMatrix[blueIndex][2]);\n> +\t\t\t\tgammaLut_[i] = gammaTable_[i * gammaTableSize / kRGBLookupSize];\n> \t\t\t}\n> \t\t}\n> \t} else {\n> @@ -1049,12 +1043,14 @@ void DebayerCpu::updateLookupTables(const DebayerParams ¶ms)\n> \t\t\tauto &red = swapRedBlueGains_ ? blue_ : red_;\n> \t\t\tauto &green = green_;\n> \t\t\tauto &blue = swapRedBlueGains_ ? red_ : blue_;\n> +\n> \t\t\tfor (unsigned int i = 0; i < kRGBLookupSize; i++) {\n> -\t\t\t\t/* Apply gamma after gain! */\n> -\t\t\t\tconst RGB lutGains = (gains * i / div).min(gammaTableSize - 1);\n> -\t\t\t\tred[i] = gammaTable_[static_cast(lutGains.r())];\n> -\t\t\t\tgreen[i] = gammaTable_[static_cast(lutGains.g())];\n> -\t\t\t\tblue[i] = gammaTable_[static_cast(lutGains.b())];\n> +\t\t\t\tconst RGB lutGains =\n> +\t\t\t\t\t(gains * (RGB(i) - blackIndex) * gammaTableSize / div)\n> +\t\t\t\t\t\t.clamp(0.0, gammaTableSize - 1);\n> +\t\t\t\tred[i] = gammaTable_[lutGains.r()];\n> +\t\t\t\tgreen[i] = gammaTable_[lutGains.g()];\n> +\t\t\t\tblue[i] = gammaTable_[lutGains.b()];\n> \t\t\t}\n> \t\t}\n> \t}","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 61F21C3301\n\tfor ;\n\tMon, 22 Jun 2026 20:00:06 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 3C52C6575C;\n\tMon, 22 Jun 2026 22:00:05 +0200 (CEST)","from us-smtp-delivery-124.mimecast.com\n\t(us-smtp-delivery-124.mimecast.com [170.10.129.124])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 8774D656D3\n\tfor ;\n\tMon, 22 Jun 2026 22:00:03 +0200 (CEST)","from mail-wr1-f70.google.com (mail-wr1-f70.google.com\n\t[209.85.221.70]) by relay.mimecast.com with ESMTP with STARTTLS\n\t(version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id\n\tus-mta-207-Fjw5vBCBNveqjznjZjU80Q-1; Mon, 22 Jun 2026 15:59:59 -0400","by mail-wr1-f70.google.com with SMTP id\n\tffacd0b85a97d-4629f312a67so4224681f8f.2\n\tfor ;\n\tMon, 22 Jun 2026 12:59:59 -0700 (PDT)","from mzamazal-thinkpadp1gen7.tpbc.csb\n\t(ip-77-48-47-4.net.vodafone.cz. 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The wrong black level and\n> > white balance application order is well visible when the white balance\n> > gains are significantly different from 1.0. Then the output differs\n> > significantly from GPU ISP output, which uses the correct order.\n> >\n> > This patch changes the computations of the lookup tables in a way that\n> > fixes both the problems.\n> >\n> > [Kieran: Fix indexing from Milans' suggestion, use new clamp]\n> > [Kieran: Use enumerate, and div updates from Laurent's suggestion]\n> \n> As for Kieran's changes:\n> \n> Reviewed-by: Milan Zamazal \n\nAnd for Milan's original code in the first place:\n\nReviewed-by: Kieran Bingham \n\n> \n> > Signed-off-by: Milan Zamazal \n> > ---\n> > src/libcamera/software_isp/debayer_cpu.cpp | 60 ++++++++++++++----------------\n> > 1 file changed, 28 insertions(+), 32 deletions(-)\n> >\n> > diff --git a/src/libcamera/software_isp/debayer_cpu.cpp b/src/libcamera/software_isp/debayer_cpu.cpp\n> > index d2596d32bbcdeaaab2e2c287e3f01ae22c442884..9d6a08b3333f988570cb5d3f7cea4c117f7c2530 100644\n> > --- a/src/libcamera/software_isp/debayer_cpu.cpp\n> > +++ b/src/libcamera/software_isp/debayer_cpu.cpp\n> > @@ -979,32 +979,20 @@ void DebayerCpuThread::process4(uint32_t frame, const uint8_t *src, uint8_t *dst\n> > \n> > void DebayerCpu::updateGammaTable(const DebayerParams ¶ms)\n> > {\n> > - const RGB blackLevel = params.blackLevel;\n> > - /* Take let's say the green channel black level */\n> > - const unsigned int blackIndex = blackLevel[1] * gammaTable_.size();\n> > const float gamma = params.gamma;\n> > const float contrastExp = params.contrastExp;\n> > \n> > - const float divisor = gammaTable_.size() - blackIndex - 1.0;\n> > - for (unsigned int i = blackIndex; i < gammaTable_.size(); i++) {\n> > - float normalized = (i - blackIndex) / divisor;\n> > + const float divisor = gammaTable_.size() - 1.0;\n> > + for (auto [i, value] : utils::enumerate(gammaTable_)) {\n> > + float normalized = i / divisor;\n> > /* Convert 0..2 to 0..infinity; avoid actual inifinity at tan(pi/2) */\n> > /* Apply simple S-curve */\n> > if (normalized < 0.5)\n> > normalized = 0.5 * std::pow(normalized / 0.5, contrastExp);\n> > else\n> > normalized = 1.0 - 0.5 * std::pow((1.0 - normalized) / 0.5, contrastExp);\n> > - gammaTable_[i] = UINT8_MAX *\n> > - std::pow(normalized, gamma);\n> > + value = UINT8_MAX * std::pow(normalized, gamma);\n> > }\n> > - /*\n> > - * Due to CCM operations, the table lookup may reach indices below the black\n> > - * level. Let's set the table values below black level to the minimum\n> > - * non-black value to prevent problems when the minimum value is\n> > - * significantly non-zero (for example, when the image should be all grey).\n> > - */\n> > - std::fill(gammaTable_.begin(), gammaTable_.begin() + blackIndex,\n> > - gammaTable_[blackIndex]);\n> > }\n> > \n> > void DebayerCpu::updateLookupTables(const DebayerParams ¶ms)\n> > @@ -1016,11 +1004,15 @@ void DebayerCpu::updateLookupTables(const DebayerParams ¶ms)\n> > if (gammaUpdateNeeded)\n> > updateGammaTable(params);\n> > \n> > + /* Processing order: black level -> gains -> gamma */\n> > auto matrixChanged = [](const Matrix &m1, const Matrix &m2) -> bool {\n> > return !std::equal(m1.data().begin(), m1.data().end(), m2.data().begin());\n> > };\n> > const unsigned int gammaTableSize = gammaTable_.size();\n> > - const double div = static_cast(kRGBLookupSize) / gammaTableSize;\n> > +\n> > + const RGB blackIndex = params.blackLevel * kRGBLookupSize;\n> > + const RGB div = (RGB(kRGBLookupSize) - blackIndex).max(1.0);\n> > +\n> > if (ccmEnabled_) {\n> > if (gammaUpdateNeeded ||\n> > matrixChanged(params.combinedMatrix, params_.combinedMatrix)) {\n> > @@ -1030,17 +1022,19 @@ void DebayerCpu::updateLookupTables(const DebayerParams ¶ms)\n> > const unsigned int redIndex = swapRedBlueGains_ ? 2 : 0;\n> > const unsigned int greenIndex = 1;\n> > const unsigned int blueIndex = swapRedBlueGains_ ? 0 : 2;\n> > +\n> > for (unsigned int i = 0; i < kRGBLookupSize; i++) {\n> > - red[i].r = std::round(i * params.combinedMatrix[redIndex][0]);\n> > - red[i].g = std::round(i * params.combinedMatrix[greenIndex][0]);\n> > - red[i].b = std::round(i * params.combinedMatrix[blueIndex][0]);\n> > - green[i].r = std::round(i * params.combinedMatrix[redIndex][1]);\n> > - green[i].g = std::round(i * params.combinedMatrix[greenIndex][1]);\n> > - green[i].b = std::round(i * params.combinedMatrix[blueIndex][1]);\n> > - blue[i].r = std::round(i * params.combinedMatrix[redIndex][2]);\n> > - blue[i].g = std::round(i * params.combinedMatrix[greenIndex][2]);\n> > - blue[i].b = std::round(i * params.combinedMatrix[blueIndex][2]);\n> > - gammaLut_[i] = gammaTable_[i / div];\n> > + const RGB rgb = ((RGB(i) - blackIndex) * kRGBLookupSize / div).max(0.0);\n> > + red[i].r = std::round(rgb.r() * params.combinedMatrix[redIndex][0]);\n> > + red[i].g = std::round(rgb.r() * params.combinedMatrix[greenIndex][0]);\n> > + red[i].b = std::round(rgb.r() * params.combinedMatrix[blueIndex][0]);\n> > + green[i].r = std::round(rgb.g() * params.combinedMatrix[redIndex][1]);\n> > + green[i].g = std::round(rgb.g() * params.combinedMatrix[greenIndex][1]);\n> > + green[i].b = std::round(rgb.g() * params.combinedMatrix[blueIndex][1]);\n> > + blue[i].r = std::round(rgb.b() * params.combinedMatrix[redIndex][2]);\n> > + blue[i].g = std::round(rgb.b() * params.combinedMatrix[greenIndex][2]);\n> > + blue[i].b = std::round(rgb.b() * params.combinedMatrix[blueIndex][2]);\n> > + gammaLut_[i] = gammaTable_[i * gammaTableSize / kRGBLookupSize];\n> > }\n> > }\n> > } else {\n> > @@ -1049,12 +1043,14 @@ void DebayerCpu::updateLookupTables(const DebayerParams ¶ms)\n> > auto &red = swapRedBlueGains_ ? blue_ : red_;\n> > auto &green = green_;\n> > auto &blue = swapRedBlueGains_ ? red_ : blue_;\n> > +\n> > for (unsigned int i = 0; i < kRGBLookupSize; i++) {\n> > - /* Apply gamma after gain! */\n> > - const RGB lutGains = (gains * i / div).min(gammaTableSize - 1);\n> > - red[i] = gammaTable_[static_cast(lutGains.r())];\n> > - green[i] = gammaTable_[static_cast(lutGains.g())];\n> > - blue[i] = gammaTable_[static_cast(lutGains.b())];\n> > + const RGB lutGains =\n> > + (gains * (RGB(i) - blackIndex) * gammaTableSize / div)\n> > + .clamp(0.0, gammaTableSize - 1);\n> > + red[i] = gammaTable_[lutGains.r()];\n> > + green[i] = gammaTable_[lutGains.g()];\n> > + blue[i] = gammaTable_[lutGains.b()];\n> > }\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 5AA43C3261\n\tfor ;\n\tTue, 23 Jun 2026 04:58:23 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 2F9BB6576C;\n\tTue, 23 Jun 2026 06:58:22 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 8A72D61F3F\n\tfor ;\n\tTue, 23 Jun 2026 06:58:20 +0200 (CEST)","from monstersaurus.ideasonboard.com\n\t(cpc89244-aztw30-2-0-cust6594.18-1.cable.virginm.net [86.31.185.195])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 0025A2D7;\n\tTue, 23 Jun 2026 06:57:41 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"u+9ot7Q/\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1782190662;\n\tbh=lO53SZf9Mn2ocUTs68rAMnO5+O2iHtTK8ImC+ixZzTw=;\n\th=In-Reply-To:References:Subject:From:Cc:To:Date:From;\n\tb=u+9ot7Q/MagoTqehlTSAzTwz/DXxqYdt4uTF/F0XuFQ4nd2n8IVfd7FcBoJut4MhV\n\tTCgHFnYlj14IBT60MArvyyQmylC/UTbyhVqtNWjMwX/N5yzON6jtUUCgoinDkhu+Yw\n\tmYYezKFHq0YJHjRzW+Wzoj5TU86CJJFF19vKU5bQ=","Content-Type":"text/plain; charset=\"utf-8\"","MIME-Version":"1.0","Content-Transfer-Encoding":"quoted-printable","In-Reply-To":"<85qzly8hxf.fsf@mzamazal-thinkpadp1gen7.tpbc.csb>","References":"<20260621-kbingham-awb-saturation-v1-0-b91ea59c6cfb@ideasonboard.com>\n\t<20260621-kbingham-awb-saturation-v1-5-b91ea59c6cfb@ideasonboard.com>\n\t<85qzly8hxf.fsf@mzamazal-thinkpadp1gen7.tpbc.csb>","Subject":"Re: [PATCH 5/7] libcamera: software_isp: Fix black level handling in\n\tCPU ISP","From":"Kieran Bingham ","Cc":"libcamera-devel@lists.libcamera.org","To":"Milan Zamazal ","Date":"Tue, 23 Jun 2026 05:58:17 +0100","Message-ID":"<178219069788.522140.1837739343760332726@ping.linuxembedded.co.uk>","User-Agent":"alot/0.9.1","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\" "}}]