[{"id":36107,"web_url":"https://patchwork.libcamera.org/comment/36107/","msgid":"","date":"2025-10-03T13:59:50","subject":"Re: [PATCH v2 1/4] ipa: rpi: pisp: Add decompand support using PiSP\n\thardware block","submitter":{"id":42,"url":"https://patchwork.libcamera.org/api/people/42/","name":"David Plowman","email":"david.plowman@raspberrypi.com"},"content":"Hi Naush\n\nThanks for the patch.\n\nOn Fri, 3 Oct 2025 at 13:18, Naushir Patuck wrote:\n>\n> From: Sena Asotani \n>\n> This patch integrates a new decompand algorithm that utilizes the PiSP\n> FE hardware block available on Raspberry Pi 5. The implementation\n> enables conversion of companded sensor data into linear format prior to\n> ISP processing.\n>\n> Changes include:\n> - Implementation of decompand logic for controller and pipe interfaces\n> - Enabling decompand block by \"rpi.decompand\" in tuning.json\n>\n> Signed-off-by: Sena Asotani \n> Signed-off-by: Naushir Patuck \n> Tested-by: Nick Hollinghurst \n> ---\n> src/ipa/rpi/controller/decompand_status.h | 8 ++++\n> src/ipa/rpi/controller/meson.build | 1 +\n> src/ipa/rpi/controller/rpi/decompand.cpp | 58 +++++++++++++++++++++++\n> src/ipa/rpi/controller/rpi/decompand.h | 31 ++++++++++++\n> src/ipa/rpi/pisp/pisp.cpp | 38 +++++++++++++++\n> 5 files changed, 136 insertions(+)\n> create mode 100644 src/ipa/rpi/controller/decompand_status.h\n> create mode 100644 src/ipa/rpi/controller/rpi/decompand.cpp\n> create mode 100644 src/ipa/rpi/controller/rpi/decompand.h\n>\n> diff --git a/src/ipa/rpi/controller/decompand_status.h b/src/ipa/rpi/controller/decompand_status.h\n> new file mode 100644\n> index 000000000000..2d9888dca4f3\n> --- /dev/null\n> +++ b/src/ipa/rpi/controller/decompand_status.h\n> @@ -0,0 +1,8 @@\n> +#pragma once\n> +\n> +#include \"libipa/pwl.h\"\n> +\n> +struct DecompandStatus {\n> + uint32_t bitdepth;\n\nI wonder if a short comment somewhere explaining how we use the\nbitdepth would be useful? It wasn't immediately clear to me that we're\nexpecting a single mode with a single bit depth to need decompanding,\nor all the modes (when bitdepth is zero).\n\nBut this minor point notwithstanding:\n\nReviewed-by: David Plowman \n\nThanks!\nDavid\n\n> + libcamera::ipa::Pwl decompandCurve;\n> +};\n> diff --git a/src/ipa/rpi/controller/meson.build b/src/ipa/rpi/controller/meson.build\n> index 74b74888bbff..c13c48539d10 100644\n> --- a/src/ipa/rpi/controller/meson.build\n> +++ b/src/ipa/rpi/controller/meson.build\n> @@ -14,6 +14,7 @@ rpi_ipa_controller_sources = files([\n> 'rpi/cac.cpp',\n> 'rpi/ccm.cpp',\n> 'rpi/contrast.cpp',\n> + 'rpi/decompand.cpp',\n> 'rpi/denoise.cpp',\n> 'rpi/dpc.cpp',\n> 'rpi/geq.cpp',\n> diff --git a/src/ipa/rpi/controller/rpi/decompand.cpp b/src/ipa/rpi/controller/rpi/decompand.cpp\n> new file mode 100644\n> index 000000000000..2036750f82f4\n> --- /dev/null\n> +++ b/src/ipa/rpi/controller/rpi/decompand.cpp\n> @@ -0,0 +1,58 @@\n> +#include \"decompand.h\"\n> +\n> +#include \n> +\n> +#include \"../decompand_status.h\"\n> +#include \"../histogram.h\"\n> +\n> +using namespace RPiController;\n> +using namespace libcamera;\n> +\n> +LOG_DEFINE_CATEGORY(RPiDecompand)\n> +\n> +#define NAME \"rpi.decompand\"\n> +\n> +Decompand::Decompand(Controller *controller)\n> + : Algorithm(controller)\n> +{\n> +}\n> +\n> +char const *Decompand::name() const\n> +{\n> + return NAME;\n> +}\n> +\n> +int Decompand::read(const libcamera::YamlObject ¶ms)\n> +{\n> + config_.bitdepth = params[\"bitdepth\"].get(0);\n> + config_.decompandCurve = params[\"decompand_curve\"].get(ipa::Pwl{});\n> + return config_.decompandCurve.empty() ? -EINVAL : 0;\n> +}\n> +\n> +void Decompand::initialise()\n> +{\n> +}\n> +\n> +void Decompand::switchMode(CameraMode const &cameraMode,\n> + [[maybe_unused]] Metadata *metadata)\n> +{\n> + mode_ = cameraMode;\n> +}\n> +\n> +void Decompand::prepare(Metadata *imageMetadata)\n> +{\n> + DecompandStatus decompandStatus;\n> +\n> + if (config_.bitdepth == 0 || mode_.bitdepth == config_.bitdepth) {\n> + decompandStatus.decompandCurve = config_.decompandCurve;\n> + imageMetadata->set(\"decompand.status\", decompandStatus);\n> + }\n> +}\n> +\n> +/* Register algorithm with the system. */\n> +static Algorithm *create(Controller *controller)\n> +{\n> + return new Decompand(controller);\n> +}\n> +\n> +static RegisterAlgorithm reg(NAME, &create);\n> diff --git a/src/ipa/rpi/controller/rpi/decompand.h b/src/ipa/rpi/controller/rpi/decompand.h\n> new file mode 100644\n> index 000000000000..38b26a21e6d5\n> --- /dev/null\n> +++ b/src/ipa/rpi/controller/rpi/decompand.h\n> @@ -0,0 +1,31 @@\n> +#pragma once\n> +\n> +#include \n> +\n> +#include \"../decompand_status.h\"\n> +\n> +#include \"algorithm.h\"\n> +\n> +namespace RPiController {\n> +\n> +struct DecompandConfig {\n> + uint32_t bitdepth;\n> + libcamera::ipa::Pwl decompandCurve;\n> +};\n> +\n> +class Decompand : public Algorithm\n> +{\n> +public:\n> + Decompand(Controller *controller = nullptr);\n> + char const *name() const override;\n> + int read(const libcamera::YamlObject ¶ms) override;\n> + void initialise() override;\n> + void switchMode(CameraMode const &cameraMode, Metadata *metadata) override;\n> + void prepare(Metadata *imageMetadata) override;\n> +\n> +private:\n> + CameraMode mode_;\n> + DecompandConfig config_;\n> +};\n> +\n> +} /* namespace RPiController */\n> diff --git a/src/ipa/rpi/pisp/pisp.cpp b/src/ipa/rpi/pisp/pisp.cpp\n> index 829b91258522..14ece12b0895 100644\n> --- a/src/ipa/rpi/pisp/pisp.cpp\n> +++ b/src/ipa/rpi/pisp/pisp.cpp\n> @@ -32,6 +32,7 @@\n> #include \"controller/cac_status.h\"\n> #include \"controller/ccm_status.h\"\n> #include \"controller/contrast_status.h\"\n> +#include \"controller/decompand_status.h\"\n> #include \"controller/denoise_algorithm.h\"\n> #include \"controller/denoise_status.h\"\n> #include \"controller/dpc_status.h\"\n> @@ -113,6 +114,25 @@ int generateLut(const ipa::Pwl &pwl, uint32_t *lut, std::size_t lutSize,\n> return 0;\n> }\n>\n> +int generateDecompandLut(const ipa::Pwl &pwl, Span lut)\n> +{\n> + if (pwl.empty())\n> + return -EINVAL;\n> +\n> + constexpr int step = 1024;\n> + for (std::size_t i = 0; i < lut.size(); ++i) {\n> + int x = i * step;\n> +\n> + int y = pwl.eval(x);\n> + if (y < 0)\n> + return -1;\n> +\n> + lut[i] = static_cast(std::min(y, 65535));\n> + }\n> +\n> + return 0;\n> +}\n> +\n> void packLscLut(uint32_t packed[NumLscVertexes][NumLscVertexes],\n> double const rgb[3][NumLscVertexes][NumLscVertexes])\n> {\n> @@ -236,6 +256,7 @@ private:\n> void applyLensShading(const AlscStatus *alscStatus,\n> pisp_be_global_config &global);\n> void applyDPC(const DpcStatus *dpcStatus, pisp_be_global_config &global);\n> + void applyDecompand(const DecompandStatus *decompandStatus);\n> void applySdn(const SdnStatus *sdnStatus, pisp_be_global_config &global);\n> void applyTdn(const TdnStatus *tdnStatus, const DeviceStatus *deviceStatus,\n> pisp_be_global_config &global);\n> @@ -351,6 +372,11 @@ void IpaPiSP::platformPrepareIsp([[maybe_unused]] const PrepareParams ¶ms,\n> if (noiseStatus)\n> applyFocusStats(noiseStatus);\n>\n> + DecompandStatus *decompandStatus =\n> + rpiMetadata.getLocked(\"decompand.status\");\n> + if (decompandStatus)\n> + applyDecompand(decompandStatus);\n> +\n> BlackLevelStatus *blackLevelStatus =\n> rpiMetadata.getLocked(\"black_level.status\");\n> if (blackLevelStatus)\n> @@ -702,6 +728,18 @@ void IpaPiSP::applyDPC(const DpcStatus *dpcStatus, pisp_be_global_config &global\n> be_->SetDpc(dpc);\n> }\n>\n> +void IpaPiSP::applyDecompand(const DecompandStatus *decompandStatus)\n> +{\n> + pisp_fe_global_config feGlobal;\n> + pisp_fe_decompand_config decompand = {};\n> +\n> + if (!generateDecompandLut(decompandStatus->decompandCurve, decompand.lut)) {\n> + fe_->SetDecompand(decompand);\n> + feGlobal.enables |= PISP_FE_ENABLE_DECOMPAND;\n> + fe_->SetGlobal(feGlobal);\n> + }\n> +}\n> +\n> void IpaPiSP::applySdn(const SdnStatus *sdnStatus, pisp_be_global_config &global)\n> {\n> pisp_be_sdn_config sdn = {};\n> --\n> 2.43.0\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 7B42FBF415\n\tfor ;\n\tFri, 3 Oct 2025 14:00:07 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id E9C736B5C2;\n\tFri, 3 Oct 2025 16:00:05 +0200 (CEST)","from mail-qk1-x72c.google.com (mail-qk1-x72c.google.com\n\t[IPv6:2607:f8b0:4864:20::72c])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 2F47269318\n\tfor ;\n\tFri, 3 Oct 2025 16:00:03 +0200 (CEST)","by mail-qk1-x72c.google.com with SMTP id\n\taf79cd13be357-8572d7b2457so258483985a.1\n\tfor ;\n\tFri, 03 Oct 2025 07:00:03 -0700 (PDT)"],"Authentication-Results":"lancelot.ideasonboard.com; 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charset=\"UTF-8\"","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":36230,"web_url":"https://patchwork.libcamera.org/comment/36230/","msgid":"<20251013145001.GK16422@pendragon.ideasonboard.com>","date":"2025-10-13T14:50:01","subject":"Re: [PATCH v2 1/4] ipa: rpi: pisp: Add decompand support using PiSP\n\thardware block","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/people/2/","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"content":"Hello Naush, Sena,\n\nOn Fri, Oct 03, 2025 at 01:15:52PM +0100, Naushir Patuck wrote:\n> From: Sena Asotani \n> \n> This patch integrates a new decompand algorithm that utilizes the PiSP\n> FE hardware block available on Raspberry Pi 5. The implementation\n> enables conversion of companded sensor data into linear format prior to\n> ISP processing.\n> \n> Changes include:\n> - Implementation of decompand logic for controller and pipe interfaces\n> - Enabling decompand block by \"rpi.decompand\" in tuning.json\n\nI've worked on something similar for i.MX8MP, with a different approach.\n\nThe companding curve is an intrinsic property of the sensor. Depending\non the sensor, it can be\n\n- hardcoded or configurable\n- when configurable, specified in different ways (e.g. piecewise linear\n function, parametric formula or selectable from presets)\n- always enabled or controllable\n\nThis creates a relatively large problem space. libcamera needs to know\nwhen a compression curve is applied by the sensor, and what curve is\nbeing applied. Additionally, it may require the ability to\nenable/disable compression, as well as the ability to configure the\ncurve.\n\nSpecifying the curve in a tuning file doesn't seem to be a good\nsolution. I've opted to support hardcoded curves only to start with (in\norder to simplify the problem), and report the curve from the sensor\nhelper. I've also added a V4L2 control ([1]) to enable and disable\ncompression, with support in the AR0144 driver([2]).\n\nDo you plan to implement proper companding support for the RPi pipeline\nhandler and IPA module ?\n\n[1] https://lore.kernel.org/linux-media/20240905225308.11267-9-laurent.pinchart@ideasonboard.com/\n[2] https://lore.kernel.org/linux-media/20240905225308.11267-10-laurent.pinchart@ideasonboard.com/\n\n> Signed-off-by: Sena Asotani \n> Signed-off-by: Naushir Patuck \n> Tested-by: Nick Hollinghurst \n> ---\n> src/ipa/rpi/controller/decompand_status.h | 8 ++++\n> src/ipa/rpi/controller/meson.build | 1 +\n> src/ipa/rpi/controller/rpi/decompand.cpp | 58 +++++++++++++++++++++++\n> src/ipa/rpi/controller/rpi/decompand.h | 31 ++++++++++++\n> src/ipa/rpi/pisp/pisp.cpp | 38 +++++++++++++++\n> 5 files changed, 136 insertions(+)\n> create mode 100644 src/ipa/rpi/controller/decompand_status.h\n> create mode 100644 src/ipa/rpi/controller/rpi/decompand.cpp\n> create mode 100644 src/ipa/rpi/controller/rpi/decompand.h\n> \n> diff --git a/src/ipa/rpi/controller/decompand_status.h b/src/ipa/rpi/controller/decompand_status.h\n> new file mode 100644\n> index 000000000000..2d9888dca4f3\n> --- /dev/null\n> +++ b/src/ipa/rpi/controller/decompand_status.h\n> @@ -0,0 +1,8 @@\n> +#pragma once\n> +\n> +#include \"libipa/pwl.h\"\n> +\n> +struct DecompandStatus {\n> +\tuint32_t bitdepth;\n> +\tlibcamera::ipa::Pwl decompandCurve;\n> +};\n> diff --git a/src/ipa/rpi/controller/meson.build b/src/ipa/rpi/controller/meson.build\n> index 74b74888bbff..c13c48539d10 100644\n> --- a/src/ipa/rpi/controller/meson.build\n> +++ b/src/ipa/rpi/controller/meson.build\n> @@ -14,6 +14,7 @@ rpi_ipa_controller_sources = files([\n> 'rpi/cac.cpp',\n> 'rpi/ccm.cpp',\n> 'rpi/contrast.cpp',\n> + 'rpi/decompand.cpp',\n> 'rpi/denoise.cpp',\n> 'rpi/dpc.cpp',\n> 'rpi/geq.cpp',\n> diff --git a/src/ipa/rpi/controller/rpi/decompand.cpp b/src/ipa/rpi/controller/rpi/decompand.cpp\n> new file mode 100644\n> index 000000000000..2036750f82f4\n> --- /dev/null\n> +++ b/src/ipa/rpi/controller/rpi/decompand.cpp\n> @@ -0,0 +1,58 @@\n> +#include \"decompand.h\"\n> +\n> +#include \n> +\n> +#include \"../decompand_status.h\"\n> +#include \"../histogram.h\"\n> +\n> +using namespace RPiController;\n> +using namespace libcamera;\n> +\n> +LOG_DEFINE_CATEGORY(RPiDecompand)\n> +\n> +#define NAME \"rpi.decompand\"\n> +\n> +Decompand::Decompand(Controller *controller)\n> +\t: Algorithm(controller)\n> +{\n> +}\n> +\n> +char const *Decompand::name() const\n> +{\n> +\treturn NAME;\n> +}\n> +\n> +int Decompand::read(const libcamera::YamlObject ¶ms)\n> +{\n> +\tconfig_.bitdepth = params[\"bitdepth\"].get(0);\n> +\tconfig_.decompandCurve = params[\"decompand_curve\"].get(ipa::Pwl{});\n> +\treturn config_.decompandCurve.empty() ? -EINVAL : 0;\n> +}\n> +\n> +void Decompand::initialise()\n> +{\n> +}\n> +\n> +void Decompand::switchMode(CameraMode const &cameraMode,\n> +\t\t\t [[maybe_unused]] Metadata *metadata)\n> +{\n> +\tmode_ = cameraMode;\n> +}\n> +\n> +void Decompand::prepare(Metadata *imageMetadata)\n> +{\n> +\tDecompandStatus decompandStatus;\n> +\n> +\tif (config_.bitdepth == 0 || mode_.bitdepth == config_.bitdepth) {\n> +\t\tdecompandStatus.decompandCurve = config_.decompandCurve;\n> +\t\timageMetadata->set(\"decompand.status\", decompandStatus);\n> +\t}\n> +}\n> +\n> +/* Register algorithm with the system. */\n> +static Algorithm *create(Controller *controller)\n> +{\n> +\treturn new Decompand(controller);\n> +}\n> +\n> +static RegisterAlgorithm reg(NAME, &create);\n> diff --git a/src/ipa/rpi/controller/rpi/decompand.h b/src/ipa/rpi/controller/rpi/decompand.h\n> new file mode 100644\n> index 000000000000..38b26a21e6d5\n> --- /dev/null\n> +++ b/src/ipa/rpi/controller/rpi/decompand.h\n> @@ -0,0 +1,31 @@\n> +#pragma once\n> +\n> +#include \n> +\n> +#include \"../decompand_status.h\"\n> +\n> +#include \"algorithm.h\"\n> +\n> +namespace RPiController {\n> +\n> +struct DecompandConfig {\n> +\tuint32_t bitdepth;\n> +\tlibcamera::ipa::Pwl decompandCurve;\n> +};\n> +\n> +class Decompand : public Algorithm\n> +{\n> +public:\n> +\tDecompand(Controller *controller = nullptr);\n> +\tchar const *name() const override;\n> +\tint read(const libcamera::YamlObject ¶ms) override;\n> +\tvoid initialise() override;\n> +\tvoid switchMode(CameraMode const &cameraMode, Metadata *metadata) override;\n> +\tvoid prepare(Metadata *imageMetadata) override;\n> +\n> +private:\n> +\tCameraMode mode_;\n> +\tDecompandConfig config_;\n> +};\n> +\n> +} /* namespace RPiController */\n> diff --git a/src/ipa/rpi/pisp/pisp.cpp b/src/ipa/rpi/pisp/pisp.cpp\n> index 829b91258522..14ece12b0895 100644\n> --- a/src/ipa/rpi/pisp/pisp.cpp\n> +++ b/src/ipa/rpi/pisp/pisp.cpp\n> @@ -32,6 +32,7 @@\n> #include \"controller/cac_status.h\"\n> #include \"controller/ccm_status.h\"\n> #include \"controller/contrast_status.h\"\n> +#include \"controller/decompand_status.h\"\n> #include \"controller/denoise_algorithm.h\"\n> #include \"controller/denoise_status.h\"\n> #include \"controller/dpc_status.h\"\n> @@ -113,6 +114,25 @@ int generateLut(const ipa::Pwl &pwl, uint32_t *lut, std::size_t lutSize,\n> \treturn 0;\n> }\n> \n> +int generateDecompandLut(const ipa::Pwl &pwl, Span lut)\n> +{\n> +\tif (pwl.empty())\n> +\t\treturn -EINVAL;\n> +\n> +\tconstexpr int step = 1024;\n> +\tfor (std::size_t i = 0; i < lut.size(); ++i) {\n> +\t\tint x = i * step;\n> +\n> +\t\tint y = pwl.eval(x);\n> +\t\tif (y < 0)\n> +\t\t\treturn -1;\n> +\n> +\t\tlut[i] = static_cast(std::min(y, 65535));\n> +\t}\n> +\n> +\treturn 0;\n> +}\n> +\n> void packLscLut(uint32_t packed[NumLscVertexes][NumLscVertexes],\n> \t\tdouble const rgb[3][NumLscVertexes][NumLscVertexes])\n> {\n> @@ -236,6 +256,7 @@ private:\n> \tvoid applyLensShading(const AlscStatus *alscStatus,\n> \t\t\t pisp_be_global_config &global);\n> \tvoid applyDPC(const DpcStatus *dpcStatus, pisp_be_global_config &global);\n> +\tvoid applyDecompand(const DecompandStatus *decompandStatus);\n> \tvoid applySdn(const SdnStatus *sdnStatus, pisp_be_global_config &global);\n> \tvoid applyTdn(const TdnStatus *tdnStatus, const DeviceStatus *deviceStatus,\n> \t\t pisp_be_global_config &global);\n> @@ -351,6 +372,11 @@ void IpaPiSP::platformPrepareIsp([[maybe_unused]] const PrepareParams ¶ms,\n> \t\tif (noiseStatus)\n> \t\t\tapplyFocusStats(noiseStatus);\n> \n> +\t\tDecompandStatus *decompandStatus =\n> +\t\t\trpiMetadata.getLocked(\"decompand.status\");\n> +\t\tif (decompandStatus)\n> +\t\t\tapplyDecompand(decompandStatus);\n> +\n> \t\tBlackLevelStatus *blackLevelStatus =\n> \t\t\trpiMetadata.getLocked(\"black_level.status\");\n> \t\tif (blackLevelStatus)\n> @@ -702,6 +728,18 @@ void IpaPiSP::applyDPC(const DpcStatus *dpcStatus, pisp_be_global_config &global\n> \tbe_->SetDpc(dpc);\n> }\n> \n> +void IpaPiSP::applyDecompand(const DecompandStatus *decompandStatus)\n> +{\n> +\tpisp_fe_global_config feGlobal;\n> +\tpisp_fe_decompand_config decompand = {};\n> +\n> +\tif (!generateDecompandLut(decompandStatus->decompandCurve, decompand.lut)) {\n> +\t\tfe_->SetDecompand(decompand);\n> +\t\tfeGlobal.enables |= PISP_FE_ENABLE_DECOMPAND;\n> +\t\tfe_->SetGlobal(feGlobal);\n> +\t}\n> +}\n> +\n> void IpaPiSP::applySdn(const SdnStatus *sdnStatus, pisp_be_global_config &global)\n> {\n> \tpisp_be_sdn_config sdn = {};","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 49DECBE080\n\tfor ;\n\tMon, 13 Oct 2025 14:50:10 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 718D66054E;\n\tMon, 13 Oct 2025 16:50:09 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 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Plowman ,\n\tNick Hollinghurst ,\n\tSena Asotani ","Subject":"Re: [PATCH v2 1/4] ipa: rpi: pisp: Add decompand support using PiSP\n\thardware block","Message-ID":"<20251013145001.GK16422@pendragon.ideasonboard.com>","References":"<20251003121821.659081-1-naush@raspberrypi.com>\n\t<20251003121821.659081-2-naush@raspberrypi.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=utf-8","Content-Disposition":"inline","In-Reply-To":"<20251003121821.659081-2-naush@raspberrypi.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":36232,"web_url":"https://patchwork.libcamera.org/comment/36232/","msgid":"","date":"2025-10-14T07:26:33","subject":"Re: [PATCH v2 1/4] ipa: rpi: pisp: Add decompand support using PiSP\n\thardware block","submitter":{"id":34,"url":"https://patchwork.libcamera.org/api/people/34/","name":"Naushir Patuck","email":"naush@raspberrypi.com"},"content":"Hi Laurent,\n\nOn Mon, 13 Oct 2025 at 15:50, Laurent Pinchart <\nlaurent.pinchart@ideasonboard.com> wrote:\n\n> Hello Naush, Sena,\n>\n> On Fri, Oct 03, 2025 at 01:15:52PM +0100, Naushir Patuck wrote:\n> > From: Sena Asotani \n> >\n> > This patch integrates a new decompand algorithm that utilizes the PiSP\n> > FE hardware block available on Raspberry Pi 5. The implementation\n> > enables conversion of companded sensor data into linear format prior to\n> > ISP processing.\n> >\n> > Changes include:\n> > - Implementation of decompand logic for controller and pipe interfaces\n> > - Enabling decompand block by \"rpi.decompand\" in tuning.json\n>\n> I've worked on something similar for i.MX8MP, with a different approach.\n>\n> The companding curve is an intrinsic property of the sensor. Depending\n> on the sensor, it can be\n>\n> - hardcoded or configurable\n> - when configurable, specified in different ways (e.g. piecewise linear\n> function, parametric formula or selectable from presets)\n> - always enabled or controllable\n>\n> This creates a relatively large problem space. libcamera needs to know\n> when a compression curve is applied by the sensor, and what curve is\n> being applied. Additionally, it may require the ability to\n> enable/disable compression, as well as the ability to configure the\n> curve.\n>\n> Specifying the curve in a tuning file doesn't seem to be a good\n> solution. I've opted to support hardcoded curves only to start with (in\n> order to simplify the problem), and report the curve from the sensor\n> helper. I've also added a V4L2 control ([1]) to enable and disable\n> compression, with support in the AR0144 driver([2]).\n>\n\nThis work for implementing decompanding was done by Sena (cc'ed) for the\nIMX585 which is not yet upstreamed. I've not worked on any sensors myself\nthat use this feature, so I can't really tell if a hard-coded curve vs a\nuser programmable one is the best approach. Having said that, I would\nagree that a V4L2 control to enable/disable companding (+ a libcamera\ncontrol of course) on the sensor is the right approach!\n\n\n> Do you plan to implement proper companding support for the RPi pipeline\n> handler and IPA module ?\n>\n\nDo you mean adding the relevant libcamera controls for use by an\napplication? Apart from that, and having a user programmable curve, this\npatch set does include everything else required for the IPA/PH to enable\nthe \"decomand\" feature in the frontend. It seems to do the right thing for\nthe IMX585 as reported by Sena.\n\nRegards,\nNaush\n\n\n> [1]\n> https://lore.kernel.org/linux-media/20240905225308.11267-9-laurent.pinchart@ideasonboard.com/\n> [2]\n> https://lore.kernel.org/linux-media/20240905225308.11267-10-laurent.pinchart@ideasonboard.com/\n>\n> > Signed-off-by: Sena Asotani \n> > Signed-off-by: Naushir Patuck \n> > Tested-by: Nick Hollinghurst \n> > ---\n> > src/ipa/rpi/controller/decompand_status.h | 8 ++++\n> > src/ipa/rpi/controller/meson.build | 1 +\n> > src/ipa/rpi/controller/rpi/decompand.cpp | 58 +++++++++++++++++++++++\n> > src/ipa/rpi/controller/rpi/decompand.h | 31 ++++++++++++\n> > src/ipa/rpi/pisp/pisp.cpp | 38 +++++++++++++++\n> > 5 files changed, 136 insertions(+)\n> > create mode 100644 src/ipa/rpi/controller/decompand_status.h\n> > create mode 100644 src/ipa/rpi/controller/rpi/decompand.cpp\n> > create mode 100644 src/ipa/rpi/controller/rpi/decompand.h\n> >\n> > diff --git a/src/ipa/rpi/controller/decompand_status.h\n> b/src/ipa/rpi/controller/decompand_status.h\n> > new file mode 100644\n> > index 000000000000..2d9888dca4f3\n> > --- /dev/null\n> > +++ b/src/ipa/rpi/controller/decompand_status.h\n> > @@ -0,0 +1,8 @@\n> > +#pragma once\n> > +\n> > +#include \"libipa/pwl.h\"\n> > +\n> > +struct DecompandStatus {\n> > + uint32_t bitdepth;\n> > + libcamera::ipa::Pwl decompandCurve;\n> > +};\n> > diff --git a/src/ipa/rpi/controller/meson.build\n> b/src/ipa/rpi/controller/meson.build\n> > index 74b74888bbff..c13c48539d10 100644\n> > --- a/src/ipa/rpi/controller/meson.build\n> > +++ b/src/ipa/rpi/controller/meson.build\n> > @@ -14,6 +14,7 @@ rpi_ipa_controller_sources = files([\n> > 'rpi/cac.cpp',\n> > 'rpi/ccm.cpp',\n> > 'rpi/contrast.cpp',\n> > + 'rpi/decompand.cpp',\n> > 'rpi/denoise.cpp',\n> > 'rpi/dpc.cpp',\n> > 'rpi/geq.cpp',\n> > diff --git a/src/ipa/rpi/controller/rpi/decompand.cpp\n> b/src/ipa/rpi/controller/rpi/decompand.cpp\n> > new file mode 100644\n> > index 000000000000..2036750f82f4\n> > --- /dev/null\n> > +++ b/src/ipa/rpi/controller/rpi/decompand.cpp\n> > @@ -0,0 +1,58 @@\n> > +#include \"decompand.h\"\n> > +\n> > +#include \n> > +\n> > +#include \"../decompand_status.h\"\n> > +#include \"../histogram.h\"\n> > +\n> > +using namespace RPiController;\n> > +using namespace libcamera;\n> > +\n> > +LOG_DEFINE_CATEGORY(RPiDecompand)\n> > +\n> > +#define NAME \"rpi.decompand\"\n> > +\n> > +Decompand::Decompand(Controller *controller)\n> > + : Algorithm(controller)\n> > +{\n> > +}\n> > +\n> > +char const *Decompand::name() const\n> > +{\n> > + return NAME;\n> > +}\n> > +\n> > +int Decompand::read(const libcamera::YamlObject ¶ms)\n> > +{\n> > + config_.bitdepth = params[\"bitdepth\"].get(0);\n> > + config_.decompandCurve =\n> params[\"decompand_curve\"].get(ipa::Pwl{});\n> > + return config_.decompandCurve.empty() ? -EINVAL : 0;\n> > +}\n> > +\n> > +void Decompand::initialise()\n> > +{\n> > +}\n> > +\n> > +void Decompand::switchMode(CameraMode const &cameraMode,\n> > + [[maybe_unused]] Metadata *metadata)\n> > +{\n> > + mode_ = cameraMode;\n> > +}\n> > +\n> > +void Decompand::prepare(Metadata *imageMetadata)\n> > +{\n> > + DecompandStatus decompandStatus;\n> > +\n> > + if (config_.bitdepth == 0 || mode_.bitdepth == config_.bitdepth) {\n> > + decompandStatus.decompandCurve = config_.decompandCurve;\n> > + imageMetadata->set(\"decompand.status\", decompandStatus);\n> > + }\n> > +}\n> > +\n> > +/* Register algorithm with the system. */\n> > +static Algorithm *create(Controller *controller)\n> > +{\n> > + return new Decompand(controller);\n> > +}\n> > +\n> > +static RegisterAlgorithm reg(NAME, &create);\n> > diff --git a/src/ipa/rpi/controller/rpi/decompand.h\n> b/src/ipa/rpi/controller/rpi/decompand.h\n> > new file mode 100644\n> > index 000000000000..38b26a21e6d5\n> > --- /dev/null\n> > +++ b/src/ipa/rpi/controller/rpi/decompand.h\n> > @@ -0,0 +1,31 @@\n> > +#pragma once\n> > +\n> > +#include \n> > +\n> > +#include \"../decompand_status.h\"\n> > +\n> > +#include \"algorithm.h\"\n> > +\n> > +namespace RPiController {\n> > +\n> > +struct DecompandConfig {\n> > + uint32_t bitdepth;\n> > + libcamera::ipa::Pwl decompandCurve;\n> > +};\n> > +\n> > +class Decompand : public Algorithm\n> > +{\n> > +public:\n> > + Decompand(Controller *controller = nullptr);\n> > + char const *name() const override;\n> > + int read(const libcamera::YamlObject ¶ms) override;\n> > + void initialise() override;\n> > + void switchMode(CameraMode const &cameraMode, Metadata *metadata)\n> override;\n> > + void prepare(Metadata *imageMetadata) override;\n> > +\n> > +private:\n> > + CameraMode mode_;\n> > + DecompandConfig config_;\n> > +};\n> > +\n> > +} /* namespace RPiController */\n> > diff --git a/src/ipa/rpi/pisp/pisp.cpp b/src/ipa/rpi/pisp/pisp.cpp\n> > index 829b91258522..14ece12b0895 100644\n> > --- a/src/ipa/rpi/pisp/pisp.cpp\n> > +++ b/src/ipa/rpi/pisp/pisp.cpp\n> > @@ -32,6 +32,7 @@\n> > #include \"controller/cac_status.h\"\n> > #include \"controller/ccm_status.h\"\n> > #include \"controller/contrast_status.h\"\n> > +#include \"controller/decompand_status.h\"\n> > #include \"controller/denoise_algorithm.h\"\n> > #include \"controller/denoise_status.h\"\n> > #include \"controller/dpc_status.h\"\n> > @@ -113,6 +114,25 @@ int generateLut(const ipa::Pwl &pwl, uint32_t *lut,\n> std::size_t lutSize,\n> > return 0;\n> > }\n> >\n> > +int generateDecompandLut(const ipa::Pwl &pwl, Span lut)\n> > +{\n> > + if (pwl.empty())\n> > + return -EINVAL;\n> > +\n> > + constexpr int step = 1024;\n> > + for (std::size_t i = 0; i < lut.size(); ++i) {\n> > + int x = i * step;\n> > +\n> > + int y = pwl.eval(x);\n> > + if (y < 0)\n> > + return -1;\n> > +\n> > + lut[i] = static_cast(std::min(y, 65535));\n> > + }\n> > +\n> > + return 0;\n> > +}\n> > +\n> > void packLscLut(uint32_t packed[NumLscVertexes][NumLscVertexes],\n> > double const rgb[3][NumLscVertexes][NumLscVertexes])\n> > {\n> > @@ -236,6 +256,7 @@ private:\n> > void applyLensShading(const AlscStatus *alscStatus,\n> > pisp_be_global_config &global);\n> > void applyDPC(const DpcStatus *dpcStatus, pisp_be_global_config\n> &global);\n> > + void applyDecompand(const DecompandStatus *decompandStatus);\n> > void applySdn(const SdnStatus *sdnStatus, pisp_be_global_config\n> &global);\n> > void applyTdn(const TdnStatus *tdnStatus, const DeviceStatus\n> *deviceStatus,\n> > pisp_be_global_config &global);\n> > @@ -351,6 +372,11 @@ void IpaPiSP::platformPrepareIsp([[maybe_unused]]\n> const PrepareParams ¶ms,\n> > if (noiseStatus)\n> > applyFocusStats(noiseStatus);\n> >\n> > + DecompandStatus *decompandStatus =\n> > +\n> rpiMetadata.getLocked(\"decompand.status\");\n> > + if (decompandStatus)\n> > + applyDecompand(decompandStatus);\n> > +\n> > BlackLevelStatus *blackLevelStatus =\n> >\n> rpiMetadata.getLocked(\"black_level.status\");\n> > if (blackLevelStatus)\n> > @@ -702,6 +728,18 @@ void IpaPiSP::applyDPC(const DpcStatus *dpcStatus,\n> pisp_be_global_config &global\n> > be_->SetDpc(dpc);\n> > }\n> >\n> > +void IpaPiSP::applyDecompand(const DecompandStatus *decompandStatus)\n> > +{\n> > + pisp_fe_global_config feGlobal;\n> > + pisp_fe_decompand_config decompand = {};\n> > +\n> > + if (!generateDecompandLut(decompandStatus->decompandCurve,\n> decompand.lut)) {\n> > + fe_->SetDecompand(decompand);\n> > + feGlobal.enables |= PISP_FE_ENABLE_DECOMPAND;\n> > + fe_->SetGlobal(feGlobal);\n> > + }\n> > +}\n> > +\n> > void IpaPiSP::applySdn(const SdnStatus *sdnStatus,\n> pisp_be_global_config &global)\n> > {\n> > pisp_be_sdn_config sdn = {};\n>\n> --\n> Regards,\n>\n> Laurent Pinchart\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 C332FBE080\n\tfor ;\n\tTue, 14 Oct 2025 07:27:13 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boundary=\"000000000000c918660641194f31\"","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":36233,"web_url":"https://patchwork.libcamera.org/comment/36233/","msgid":"<20251014075958.GA30747@pendragon.ideasonboard.com>","date":"2025-10-14T07:59:58","subject":"Re: [PATCH v2 1/4] ipa: rpi: pisp: Add decompand support using PiSP\n\thardware block","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/people/2/","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"content":"Hi Naush,\n\nOn Tue, Oct 14, 2025 at 08:26:33AM +0100, Naushir Patuck wrote:\n> On Mon, 13 Oct 2025 at 15:50, Laurent Pinchart wrote:\n> > On Fri, Oct 03, 2025 at 01:15:52PM +0100, Naushir Patuck wrote:\n> > > From: Sena Asotani \n> > >\n> > > This patch integrates a new decompand algorithm that utilizes the PiSP\n> > > FE hardware block available on Raspberry Pi 5. The implementation\n> > > enables conversion of companded sensor data into linear format prior to\n> > > ISP processing.\n> > >\n> > > Changes include:\n> > > - Implementation of decompand logic for controller and pipe interfaces\n> > > - Enabling decompand block by \"rpi.decompand\" in tuning.json\n> >\n> > I've worked on something similar for i.MX8MP, with a different approach.\n> >\n> > The companding curve is an intrinsic property of the sensor. Depending\n> > on the sensor, it can be\n> >\n> > - hardcoded or configurable\n> > - when configurable, specified in different ways (e.g. piecewise linear\n> > function, parametric formula or selectable from presets)\n> > - always enabled or controllable\n> >\n> > This creates a relatively large problem space. libcamera needs to know\n> > when a compression curve is applied by the sensor, and what curve is\n> > being applied. Additionally, it may require the ability to\n> > enable/disable compression, as well as the ability to configure the\n> > curve.\n> >\n> > Specifying the curve in a tuning file doesn't seem to be a good\n> > solution. I've opted to support hardcoded curves only to start with (in\n> > order to simplify the problem), and report the curve from the sensor\n> > helper. I've also added a V4L2 control ([1]) to enable and disable\n> > compression, with support in the AR0144 driver([2]).\n> \n> This work for implementing decompanding was done by Sena (cc'ed) for the\n> IMX585 which is not yet upstreamed. I've not worked on any sensors myself\n> that use this feature, so I can't really tell if a hard-coded curve vs a\n> user programmable one is the best approach.\n\nI've seen both cases implemented in sensors, so we need to support\nhardcoded curves, and may want to support configurable curves.\n\n> Having said that, I would\n> agree that a V4L2 control to enable/disable companding (+ a libcamera\n> control of course) on the sensor is the right approach!\n\nOn the camera side I expect it would be a SensorConfiguration parameter\nrather than a control.\n\n> > Do you plan to implement proper companding support for the RPi pipeline\n> > handler and IPA module ?\n> \n> Do you mean adding the relevant libcamera controls for use by an\n> application? Apart from that, and having a user programmable curve, this\n> patch set does include everything else required for the IPA/PH to enable\n> the \"decomand\" feature in the frontend. It seems to do the right thing for\n> the IMX585 as reported by Sena.\n\nI meant\n\n- Making companding dynamically selectable by the user\n- Optionally supporting user-specific curves\n- Moving the curve from tuning files to sensor helpers\n\n> > [1] https://lore.kernel.org/linux-media/20240905225308.11267-9-laurent.pinchart@ideasonboard.com/\n> > [2] https://lore.kernel.org/linux-media/20240905225308.11267-10-laurent.pinchart@ideasonboard.com/\n> >\n> > > Signed-off-by: Sena Asotani \n> > > Signed-off-by: Naushir Patuck \n> > > Tested-by: Nick Hollinghurst \n> > > ---\n> > > src/ipa/rpi/controller/decompand_status.h | 8 ++++\n> > > src/ipa/rpi/controller/meson.build | 1 +\n> > > src/ipa/rpi/controller/rpi/decompand.cpp | 58 +++++++++++++++++++++++\n> > > src/ipa/rpi/controller/rpi/decompand.h | 31 ++++++++++++\n> > > src/ipa/rpi/pisp/pisp.cpp | 38 +++++++++++++++\n> > > 5 files changed, 136 insertions(+)\n> > > create mode 100644 src/ipa/rpi/controller/decompand_status.h\n> > > create mode 100644 src/ipa/rpi/controller/rpi/decompand.cpp\n> > > create mode 100644 src/ipa/rpi/controller/rpi/decompand.h\n> > >\n> > > diff --git a/src/ipa/rpi/controller/decompand_status.h\n> > b/src/ipa/rpi/controller/decompand_status.h\n> > > new file mode 100644\n> > > index 000000000000..2d9888dca4f3\n> > > --- /dev/null\n> > > +++ b/src/ipa/rpi/controller/decompand_status.h\n> > > @@ -0,0 +1,8 @@\n> > > +#pragma once\n> > > +\n> > > +#include \"libipa/pwl.h\"\n> > > +\n> > > +struct DecompandStatus {\n> > > + uint32_t bitdepth;\n> > > + libcamera::ipa::Pwl decompandCurve;\n> > > +};\n> > > diff --git a/src/ipa/rpi/controller/meson.build\n> > b/src/ipa/rpi/controller/meson.build\n> > > index 74b74888bbff..c13c48539d10 100644\n> > > --- a/src/ipa/rpi/controller/meson.build\n> > > +++ b/src/ipa/rpi/controller/meson.build\n> > > @@ -14,6 +14,7 @@ rpi_ipa_controller_sources = files([\n> > > 'rpi/cac.cpp',\n> > > 'rpi/ccm.cpp',\n> > > 'rpi/contrast.cpp',\n> > > + 'rpi/decompand.cpp',\n> > > 'rpi/denoise.cpp',\n> > > 'rpi/dpc.cpp',\n> > > 'rpi/geq.cpp',\n> > > diff --git a/src/ipa/rpi/controller/rpi/decompand.cpp\n> > b/src/ipa/rpi/controller/rpi/decompand.cpp\n> > > new file mode 100644\n> > > index 000000000000..2036750f82f4\n> > > --- /dev/null\n> > > +++ b/src/ipa/rpi/controller/rpi/decompand.cpp\n> > > @@ -0,0 +1,58 @@\n> > > +#include \"decompand.h\"\n> > > +\n> > > +#include \n> > > +\n> > > +#include \"../decompand_status.h\"\n> > > +#include \"../histogram.h\"\n> > > +\n> > > +using namespace RPiController;\n> > > +using namespace libcamera;\n> > > +\n> > > +LOG_DEFINE_CATEGORY(RPiDecompand)\n> > > +\n> > > +#define NAME \"rpi.decompand\"\n> > > +\n> > > +Decompand::Decompand(Controller *controller)\n> > > + : Algorithm(controller)\n> > > +{\n> > > +}\n> > > +\n> > > +char const *Decompand::name() const\n> > > +{\n> > > + return NAME;\n> > > +}\n> > > +\n> > > +int Decompand::read(const libcamera::YamlObject ¶ms)\n> > > +{\n> > > + config_.bitdepth = params[\"bitdepth\"].get(0);\n> > > + config_.decompandCurve =\n> > params[\"decompand_curve\"].get(ipa::Pwl{});\n> > > + return config_.decompandCurve.empty() ? -EINVAL : 0;\n> > > +}\n> > > +\n> > > +void Decompand::initialise()\n> > > +{\n> > > +}\n> > > +\n> > > +void Decompand::switchMode(CameraMode const &cameraMode,\n> > > + [[maybe_unused]] Metadata *metadata)\n> > > +{\n> > > + mode_ = cameraMode;\n> > > +}\n> > > +\n> > > +void Decompand::prepare(Metadata *imageMetadata)\n> > > +{\n> > > + DecompandStatus decompandStatus;\n> > > +\n> > > + if (config_.bitdepth == 0 || mode_.bitdepth == config_.bitdepth) {\n> > > + decompandStatus.decompandCurve = config_.decompandCurve;\n> > > + imageMetadata->set(\"decompand.status\", decompandStatus);\n> > > + }\n> > > +}\n> > > +\n> > > +/* Register algorithm with the system. */\n> > > +static Algorithm *create(Controller *controller)\n> > > +{\n> > > + return new Decompand(controller);\n> > > +}\n> > > +\n> > > +static RegisterAlgorithm reg(NAME, &create);\n> > > diff --git a/src/ipa/rpi/controller/rpi/decompand.h\n> > b/src/ipa/rpi/controller/rpi/decompand.h\n> > > new file mode 100644\n> > > index 000000000000..38b26a21e6d5\n> > > --- /dev/null\n> > > +++ b/src/ipa/rpi/controller/rpi/decompand.h\n> > > @@ -0,0 +1,31 @@\n> > > +#pragma once\n> > > +\n> > > +#include \n> > > +\n> > > +#include \"../decompand_status.h\"\n> > > +\n> > > +#include \"algorithm.h\"\n> > > +\n> > > +namespace RPiController {\n> > > +\n> > > +struct DecompandConfig {\n> > > + uint32_t bitdepth;\n> > > + libcamera::ipa::Pwl decompandCurve;\n> > > +};\n> > > +\n> > > +class Decompand : public Algorithm\n> > > +{\n> > > +public:\n> > > + Decompand(Controller *controller = nullptr);\n> > > + char const *name() const override;\n> > > + int read(const libcamera::YamlObject ¶ms) override;\n> > > + void initialise() override;\n> > > + void switchMode(CameraMode const &cameraMode, Metadata *metadata)\n> > override;\n> > > + void prepare(Metadata *imageMetadata) override;\n> > > +\n> > > +private:\n> > > + CameraMode mode_;\n> > > + DecompandConfig config_;\n> > > +};\n> > > +\n> > > +} /* namespace RPiController */\n> > > diff --git a/src/ipa/rpi/pisp/pisp.cpp b/src/ipa/rpi/pisp/pisp.cpp\n> > > index 829b91258522..14ece12b0895 100644\n> > > --- a/src/ipa/rpi/pisp/pisp.cpp\n> > > +++ b/src/ipa/rpi/pisp/pisp.cpp\n> > > @@ -32,6 +32,7 @@\n> > > #include \"controller/cac_status.h\"\n> > > #include \"controller/ccm_status.h\"\n> > > #include \"controller/contrast_status.h\"\n> > > +#include \"controller/decompand_status.h\"\n> > > #include \"controller/denoise_algorithm.h\"\n> > > #include \"controller/denoise_status.h\"\n> > > #include \"controller/dpc_status.h\"\n> > > @@ -113,6 +114,25 @@ int generateLut(const ipa::Pwl &pwl, uint32_t *lut,\n> > std::size_t lutSize,\n> > > return 0;\n> > > }\n> > >\n> > > +int generateDecompandLut(const ipa::Pwl &pwl, Span lut)\n> > > +{\n> > > + if (pwl.empty())\n> > > + return -EINVAL;\n> > > +\n> > > + constexpr int step = 1024;\n> > > + for (std::size_t i = 0; i < lut.size(); ++i) {\n> > > + int x = i * step;\n> > > +\n> > > + int y = pwl.eval(x);\n> > > + if (y < 0)\n> > > + return -1;\n> > > +\n> > > + lut[i] = static_cast(std::min(y, 65535));\n> > > + }\n> > > +\n> > > + return 0;\n> > > +}\n> > > +\n> > > void packLscLut(uint32_t packed[NumLscVertexes][NumLscVertexes],\n> > > double const rgb[3][NumLscVertexes][NumLscVertexes])\n> > > {\n> > > @@ -236,6 +256,7 @@ private:\n> > > void applyLensShading(const AlscStatus *alscStatus,\n> > > pisp_be_global_config &global);\n> > > void applyDPC(const DpcStatus *dpcStatus, pisp_be_global_config\n> > &global);\n> > > + void applyDecompand(const DecompandStatus *decompandStatus);\n> > > void applySdn(const SdnStatus *sdnStatus, pisp_be_global_config\n> > &global);\n> > > void applyTdn(const TdnStatus *tdnStatus, const DeviceStatus\n> > *deviceStatus,\n> > > pisp_be_global_config &global);\n> > > @@ -351,6 +372,11 @@ void IpaPiSP::platformPrepareIsp([[maybe_unused]]\n> > const PrepareParams ¶ms,\n> > > if (noiseStatus)\n> > > applyFocusStats(noiseStatus);\n> > >\n> > > + DecompandStatus *decompandStatus =\n> > > +\n> > rpiMetadata.getLocked(\"decompand.status\");\n> > > + if (decompandStatus)\n> > > + applyDecompand(decompandStatus);\n> > > +\n> > > BlackLevelStatus *blackLevelStatus =\n> > >\n> > rpiMetadata.getLocked(\"black_level.status\");\n> > > if (blackLevelStatus)\n> > > @@ -702,6 +728,18 @@ void IpaPiSP::applyDPC(const DpcStatus *dpcStatus,\n> > pisp_be_global_config &global\n> > > be_->SetDpc(dpc);\n> > > }\n> > >\n> > > +void IpaPiSP::applyDecompand(const DecompandStatus *decompandStatus)\n> > > +{\n> > > + pisp_fe_global_config feGlobal;\n> > > + pisp_fe_decompand_config decompand = {};\n> > > +\n> > > + if (!generateDecompandLut(decompandStatus->decompandCurve,\n> > decompand.lut)) {\n> > > + fe_->SetDecompand(decompand);\n> > > + feGlobal.enables |= PISP_FE_ENABLE_DECOMPAND;\n> > > + fe_->SetGlobal(feGlobal);\n> > > + }\n> > > +}\n> > > +\n> > > void IpaPiSP::applySdn(const SdnStatus *sdnStatus,\n> > pisp_be_global_config &global)\n> > > {\n> > > pisp_be_sdn_config sdn = {};","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 39D17BE080\n\tfor ;\n\tTue, 14 Oct 2025 08:00:09 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 4598660580;\n\tTue, 14 Oct 2025 10:00:08 +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 58DF660316\n\tfor ;\n\tTue, 14 Oct 2025 10:00:06 +0200 (CEST)","from pendragon.ideasonboard.com 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decompand support using PiSP\n\thardware block","Message-ID":"<20251014075958.GA30747@pendragon.ideasonboard.com>","References":"<20251003121821.659081-1-naush@raspberrypi.com>\n\t<20251003121821.659081-2-naush@raspberrypi.com>\n\t<20251013145001.GK16422@pendragon.ideasonboard.com>\n\t","MIME-Version":"1.0","Content-Type":"text/plain; charset=utf-8","Content-Disposition":"inline","In-Reply-To":"","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":36292,"web_url":"https://patchwork.libcamera.org/comment/36292/","msgid":"","date":"2025-10-16T07:33:42","subject":"Re: [PATCH v2 1/4] ipa: rpi: pisp: Add decompand support using PiSP\n\thardware block","submitter":{"id":34,"url":"https://patchwork.libcamera.org/api/people/34/","name":"Naushir Patuck","email":"naush@raspberrypi.com"},"content":"Hi Laurent,\n\nOn Tue, 14 Oct 2025 at 09:00, Laurent Pinchart <\nlaurent.pinchart@ideasonboard.com> wrote:\n\n> Hi Naush,\n>\n> On Tue, Oct 14, 2025 at 08:26:33AM +0100, Naushir Patuck wrote:\n> > On Mon, 13 Oct 2025 at 15:50, Laurent Pinchart wrote:\n> > > On Fri, Oct 03, 2025 at 01:15:52PM +0100, Naushir Patuck wrote:\n> > > > From: Sena Asotani \n> > > >\n> > > > This patch integrates a new decompand algorithm that utilizes the\n> PiSP\n> > > > FE hardware block available on Raspberry Pi 5. The implementation\n> > > > enables conversion of companded sensor data into linear format prior\n> to\n> > > > ISP processing.\n> > > >\n> > > > Changes include:\n> > > > - Implementation of decompand logic for controller and pipe\n> interfaces\n> > > > - Enabling decompand block by \"rpi.decompand\" in tuning.json\n> > >\n> > > I've worked on something similar for i.MX8MP, with a different\n> approach.\n> > >\n> > > The companding curve is an intrinsic property of the sensor. Depending\n> > > on the sensor, it can be\n> > >\n> > > - hardcoded or configurable\n> > > - when configurable, specified in different ways (e.g. piecewise linear\n> > > function, parametric formula or selectable from presets)\n> > > - always enabled or controllable\n> > >\n> > > This creates a relatively large problem space. libcamera needs to know\n> > > when a compression curve is applied by the sensor, and what curve is\n> > > being applied. Additionally, it may require the ability to\n> > > enable/disable compression, as well as the ability to configure the\n> > > curve.\n> > >\n> > > Specifying the curve in a tuning file doesn't seem to be a good\n> > > solution. I've opted to support hardcoded curves only to start with (in\n> > > order to simplify the problem), and report the curve from the sensor\n> > > helper. I've also added a V4L2 control ([1]) to enable and disable\n> > > compression, with support in the AR0144 driver([2]).\n> >\n> > This work for implementing decompanding was done by Sena (cc'ed) for the\n> > IMX585 which is not yet upstreamed. I've not worked on any sensors\n> myself\n> > that use this feature, so I can't really tell if a hard-coded curve vs a\n> > user programmable one is the best approach.\n>\n> I've seen both cases implemented in sensors, so we need to support\n> hardcoded curves, and may want to support configurable curves.\n>\n> > Having said that, I would\n> > agree that a V4L2 control to enable/disable companding (+ a libcamera\n> > control of course) on the sensor is the right approach!\n>\n> On the camera side I expect it would be a SensorConfiguration parameter\n> rather than a control.\n>\n> > > Do you plan to implement proper companding support for the RPi pipeline\n> > > handler and IPA module ?\n> >\n> > Do you mean adding the relevant libcamera controls for use by an\n> > application? Apart from that, and having a user programmable curve, this\n> > patch set does include everything else required for the IPA/PH to enable\n> > the \"decomand\" feature in the frontend. It seems to do the right thing\n> for\n> > the IMX585 as reported by Sena.\n>\n> I meant\n>\n> - Making companding dynamically selectable by the user\n> - Optionally supporting user-specific curves\n> - Moving the curve from tuning files to sensor helpers\n>\n\nI don't have any experience with using companding in sensors. I don't even\nhave access to the IMX585 that this feature is developed for. So a few\nbasic questions to help my understanding :)\n\n- Should this be a user accessible control(s)? Do you see a user needing\nto enable/disable this? Perhaps this should be a decision made only by the\npipeline handler.\n- Should the curve (if adjustable) be perhaps defined in the sensor driver\nand extracted to userland via the sensor helper?\n- I'm struggling to see why a sensor device would allow adjustable\ncompanding curves, is there a use-case you know about where this is needed?\n\nRegards,\nNaush\n\n\n>\n> > > [1]\n> https://lore.kernel.org/linux-media/20240905225308.11267-9-laurent.pinchart@ideasonboard.com/\n> > > [2]\n> https://lore.kernel.org/linux-media/20240905225308.11267-10-laurent.pinchart@ideasonboard.com/\n> > >\n> > > > Signed-off-by: Sena Asotani \n> > > > Signed-off-by: Naushir Patuck \n> > > > Tested-by: Nick Hollinghurst \n> > > > ---\n> > > > src/ipa/rpi/controller/decompand_status.h | 8 ++++\n> > > > src/ipa/rpi/controller/meson.build | 1 +\n> > > > src/ipa/rpi/controller/rpi/decompand.cpp | 58\n> +++++++++++++++++++++++\n> > > > src/ipa/rpi/controller/rpi/decompand.h | 31 ++++++++++++\n> > > > src/ipa/rpi/pisp/pisp.cpp | 38 +++++++++++++++\n> > > > 5 files changed, 136 insertions(+)\n> > > > create mode 100644 src/ipa/rpi/controller/decompand_status.h\n> > > > create mode 100644 src/ipa/rpi/controller/rpi/decompand.cpp\n> > > > create mode 100644 src/ipa/rpi/controller/rpi/decompand.h\n> > > >\n> > > > diff --git a/src/ipa/rpi/controller/decompand_status.h\n> > > b/src/ipa/rpi/controller/decompand_status.h\n> > > > new file mode 100644\n> > > > index 000000000000..2d9888dca4f3\n> > > > --- /dev/null\n> > > > +++ b/src/ipa/rpi/controller/decompand_status.h\n> > > > @@ -0,0 +1,8 @@\n> > > > +#pragma once\n> > > > +\n> > > > +#include \"libipa/pwl.h\"\n> > > > +\n> > > > +struct DecompandStatus {\n> > > > + uint32_t bitdepth;\n> > > > + libcamera::ipa::Pwl decompandCurve;\n> > > > +};\n> > > > diff --git a/src/ipa/rpi/controller/meson.build\n> > > b/src/ipa/rpi/controller/meson.build\n> > > > index 74b74888bbff..c13c48539d10 100644\n> > > > --- a/src/ipa/rpi/controller/meson.build\n> > > > +++ b/src/ipa/rpi/controller/meson.build\n> > > > @@ -14,6 +14,7 @@ rpi_ipa_controller_sources = files([\n> > > > 'rpi/cac.cpp',\n> > > > 'rpi/ccm.cpp',\n> > > > 'rpi/contrast.cpp',\n> > > > + 'rpi/decompand.cpp',\n> > > > 'rpi/denoise.cpp',\n> > > > 'rpi/dpc.cpp',\n> > > > 'rpi/geq.cpp',\n> > > > diff --git a/src/ipa/rpi/controller/rpi/decompand.cpp\n> > > b/src/ipa/rpi/controller/rpi/decompand.cpp\n> > > > new file mode 100644\n> > > > index 000000000000..2036750f82f4\n> > > > --- /dev/null\n> > > > +++ b/src/ipa/rpi/controller/rpi/decompand.cpp\n> > > > @@ -0,0 +1,58 @@\n> > > > +#include \"decompand.h\"\n> > > > +\n> > > > +#include \n> > > > +\n> > > > +#include \"../decompand_status.h\"\n> > > > +#include \"../histogram.h\"\n> > > > +\n> > > > +using namespace RPiController;\n> > > > +using namespace libcamera;\n> > > > +\n> > > > +LOG_DEFINE_CATEGORY(RPiDecompand)\n> > > > +\n> > > > +#define NAME \"rpi.decompand\"\n> > > > +\n> > > > +Decompand::Decompand(Controller *controller)\n> > > > + : Algorithm(controller)\n> > > > +{\n> > > > +}\n> > > > +\n> > > > +char const *Decompand::name() const\n> > > > +{\n> > > > + return NAME;\n> > > > +}\n> > > > +\n> > > > +int Decompand::read(const libcamera::YamlObject ¶ms)\n> > > > +{\n> > > > + config_.bitdepth = params[\"bitdepth\"].get(0);\n> > > > + config_.decompandCurve =\n> > > params[\"decompand_curve\"].get(ipa::Pwl{});\n> > > > + return config_.decompandCurve.empty() ? -EINVAL : 0;\n> > > > +}\n> > > > +\n> > > > +void Decompand::initialise()\n> > > > +{\n> > > > +}\n> > > > +\n> > > > +void Decompand::switchMode(CameraMode const &cameraMode,\n> > > > + [[maybe_unused]] Metadata *metadata)\n> > > > +{\n> > > > + mode_ = cameraMode;\n> > > > +}\n> > > > +\n> > > > +void Decompand::prepare(Metadata *imageMetadata)\n> > > > +{\n> > > > + DecompandStatus decompandStatus;\n> > > > +\n> > > > + if (config_.bitdepth == 0 || mode_.bitdepth ==\n> config_.bitdepth) {\n> > > > + decompandStatus.decompandCurve =\n> config_.decompandCurve;\n> > > > + imageMetadata->set(\"decompand.status\",\n> decompandStatus);\n> > > > + }\n> > > > +}\n> > > > +\n> > > > +/* Register algorithm with the system. */\n> > > > +static Algorithm *create(Controller *controller)\n> > > > +{\n> > > > + return new Decompand(controller);\n> > > > +}\n> > > > +\n> > > > +static RegisterAlgorithm reg(NAME, &create);\n> > > > diff --git a/src/ipa/rpi/controller/rpi/decompand.h\n> > > b/src/ipa/rpi/controller/rpi/decompand.h\n> > > > new file mode 100644\n> > > > index 000000000000..38b26a21e6d5\n> > > > --- /dev/null\n> > > > +++ b/src/ipa/rpi/controller/rpi/decompand.h\n> > > > @@ -0,0 +1,31 @@\n> > > > +#pragma once\n> > > > +\n> > > > +#include \n> > > > +\n> > > > +#include \"../decompand_status.h\"\n> > > > +\n> > > > +#include \"algorithm.h\"\n> > > > +\n> > > > +namespace RPiController {\n> > > > +\n> > > > +struct DecompandConfig {\n> > > > + uint32_t bitdepth;\n> > > > + libcamera::ipa::Pwl decompandCurve;\n> > > > +};\n> > > > +\n> > > > +class Decompand : public Algorithm\n> > > > +{\n> > > > +public:\n> > > > + Decompand(Controller *controller = nullptr);\n> > > > + char const *name() const override;\n> > > > + int read(const libcamera::YamlObject ¶ms) override;\n> > > > + void initialise() override;\n> > > > + void switchMode(CameraMode const &cameraMode, Metadata\n> *metadata)\n> > > override;\n> > > > + void prepare(Metadata *imageMetadata) override;\n> > > > +\n> > > > +private:\n> > > > + CameraMode mode_;\n> > > > + DecompandConfig config_;\n> > > > +};\n> > > > +\n> > > > +} /* namespace RPiController */\n> > > > diff --git a/src/ipa/rpi/pisp/pisp.cpp b/src/ipa/rpi/pisp/pisp.cpp\n> > > > index 829b91258522..14ece12b0895 100644\n> > > > --- a/src/ipa/rpi/pisp/pisp.cpp\n> > > > +++ b/src/ipa/rpi/pisp/pisp.cpp\n> > > > @@ -32,6 +32,7 @@\n> > > > #include \"controller/cac_status.h\"\n> > > > #include \"controller/ccm_status.h\"\n> > > > #include \"controller/contrast_status.h\"\n> > > > +#include \"controller/decompand_status.h\"\n> > > > #include \"controller/denoise_algorithm.h\"\n> > > > #include \"controller/denoise_status.h\"\n> > > > #include \"controller/dpc_status.h\"\n> > > > @@ -113,6 +114,25 @@ int generateLut(const ipa::Pwl &pwl, uint32_t\n> *lut,\n> > > std::size_t lutSize,\n> > > > return 0;\n> > > > }\n> > > >\n> > > > +int generateDecompandLut(const ipa::Pwl &pwl, Span lut)\n> > > > +{\n> > > > + if (pwl.empty())\n> > > > + return -EINVAL;\n> > > > +\n> > > > + constexpr int step = 1024;\n> > > > + for (std::size_t i = 0; i < lut.size(); ++i) {\n> > > > + int x = i * step;\n> > > > +\n> > > > + int y = pwl.eval(x);\n> > > > + if (y < 0)\n> > > > + return -1;\n> > > > +\n> > > > + lut[i] = static_cast(std::min(y, 65535));\n> > > > + }\n> > > > +\n> > > > + return 0;\n> > > > +}\n> > > > +\n> > > > void packLscLut(uint32_t packed[NumLscVertexes][NumLscVertexes],\n> > > > double const rgb[3][NumLscVertexes][NumLscVertexes])\n> > > > {\n> > > > @@ -236,6 +256,7 @@ private:\n> > > > void applyLensShading(const AlscStatus *alscStatus,\n> > > > pisp_be_global_config &global);\n> > > > void applyDPC(const DpcStatus *dpcStatus, pisp_be_global_config\n> > > &global);\n> > > > + void applyDecompand(const DecompandStatus *decompandStatus);\n> > > > void applySdn(const SdnStatus *sdnStatus, pisp_be_global_config\n> > > &global);\n> > > > void applyTdn(const TdnStatus *tdnStatus, const DeviceStatus\n> > > *deviceStatus,\n> > > > pisp_be_global_config &global);\n> > > > @@ -351,6 +372,11 @@ void\n> IpaPiSP::platformPrepareIsp([[maybe_unused]]\n> > > const PrepareParams ¶ms,\n> > > > if (noiseStatus)\n> > > > applyFocusStats(noiseStatus);\n> > > >\n> > > > + DecompandStatus *decompandStatus =\n> > > > +\n> > > rpiMetadata.getLocked(\"decompand.status\");\n> > > > + if (decompandStatus)\n> > > > + applyDecompand(decompandStatus);\n> > > > +\n> > > > BlackLevelStatus *blackLevelStatus =\n> > > >\n> > > rpiMetadata.getLocked(\"black_level.status\");\n> > > > if (blackLevelStatus)\n> > > > @@ -702,6 +728,18 @@ void IpaPiSP::applyDPC(const DpcStatus\n> *dpcStatus,\n> > > pisp_be_global_config &global\n> > > > be_->SetDpc(dpc);\n> > > > }\n> > > >\n> > > > +void IpaPiSP::applyDecompand(const DecompandStatus *decompandStatus)\n> > > > +{\n> > > > + pisp_fe_global_config feGlobal;\n> > > > + pisp_fe_decompand_config decompand = {};\n> > > > +\n> > > > + if (!generateDecompandLut(decompandStatus->decompandCurve,\n> > > decompand.lut)) {\n> > > > + fe_->SetDecompand(decompand);\n> > > > + feGlobal.enables |= PISP_FE_ENABLE_DECOMPAND;\n> > > > + fe_->SetGlobal(feGlobal);\n> > > > + }\n> > > > +}\n> > > > +\n> > > > void IpaPiSP::applySdn(const SdnStatus *sdnStatus,\n> > > pisp_be_global_config &global)\n> > > > {\n> > > > pisp_be_sdn_config sdn = {};\n>\n> --\n> Regards,\n>\n> Laurent 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