From patchwork Wed Jul 3 10:39:48 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Klug X-Patchwork-Id: 20501 Return-Path: X-Original-To: parsemail@patchwork.libcamera.org Delivered-To: parsemail@patchwork.libcamera.org Received: from lancelot.ideasonboard.com (lancelot.ideasonboard.com [92.243.16.209]) by patchwork.libcamera.org (Postfix) with ESMTPS id 3F83ABEFBE for ; Wed, 3 Jul 2024 10:40:17 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id DE92862E25; Wed, 3 Jul 2024 12:40:16 +0200 (CEST) Authentication-Results: lancelot.ideasonboard.com; dkim=pass (1024-bit key; unprotected) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="GMH3gIv1"; dkim-atps=neutral Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id 2246C62C95 for ; Wed, 3 Jul 2024 12:40:15 +0200 (CEST) Received: from ideasonboard.com (unknown [IPv6:2a00:6020:448c:6c00:9263:c199:9587:576]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 125046D6; Wed, 3 Jul 2024 12:39:47 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1720003187; bh=dBTzKx/UVMGyiAOzeu1YD+O1cwsF+xeLRK6elxGwmXo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GMH3gIv13mGr9tTo4qNV8n0Y1uhTKB5tyr3YqJDLQDCAOqJcOJe/vaXMiSKL1dma4 2o3FlTq2u7ZTDy6TbVuB3Eshou38jfSKO7t//p0cA1+cK1PS52Z/LlGDTtp+9FUOrx DHSB7DSWjTuA5Sn5Mr7DjV3PgI/IZgd1iGNzlUxY= From: Stefan Klug To: libcamera-devel@lists.libcamera.org Cc: Stefan Klug Subject: [PATCH v2 1/6] ipa: libipa: Add black levels to camera sensor helper Date: Wed, 3 Jul 2024 12:39:48 +0200 Message-ID: <20240703104004.184783-2-stefan.klug@ideasonboard.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240703104004.184783-1-stefan.klug@ideasonboard.com> References: <20240703104004.184783-1-stefan.klug@ideasonboard.com> MIME-Version: 1.0 X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libcamera-devel-bounces@lists.libcamera.org Sender: "libcamera-devel" For a proper tuning process we need to know the sensor black levels. In most cases these are fixed and not reported by the kernel driver. Store them inside the sensor helpers for later retrieval by the algorithms. Add black level value corresponding to the data pedestal for three initial sensors as documented in the datasheets. More should be added, eventually filling the gaps for all supported sensors. Signed-off-by: Stefan Klug Reviewed-by: Paul Elder Reviewed-by: Kieran Bingham Reviewed-by: Laurent Pinchart --- src/ipa/libipa/camera_sensor_helper.cpp | 27 +++++++++++++++++++++++++ src/ipa/libipa/camera_sensor_helper.h | 3 +++ 2 files changed, 30 insertions(+) diff --git a/src/ipa/libipa/camera_sensor_helper.cpp b/src/ipa/libipa/camera_sensor_helper.cpp index 782ff9904e81..3d0e756927f0 100644 --- a/src/ipa/libipa/camera_sensor_helper.cpp +++ b/src/ipa/libipa/camera_sensor_helper.cpp @@ -47,6 +47,30 @@ namespace ipa { * function. */ +/** + * \fn CameraSensorHelper::blackLevel() + * \brief Fetch the black level of the sensor + * + * This function returns the black level of the sensor scaled to a 16bit pixel + * width. If it is unknown an empty optional is returned. + * + * Black levels are typically the result of the following phenomena: + * - Pedestal added by the sensor to pixel values. They are typically fixed, + * sometimes programmable and should be reported in datasheets (but + * documentation is not always available). + * - Dark currents and other physical effects that add charge to pixels in the + * absence of light. Those can depend on the integration time and the sensor + * die temperature, and their contribution to pixel values depend on the + * sensor gains. + * + * The pedestal is usually the value with the biggest contribution to the + * overall black level. In most cases it is either known before or in rare cases + * (There is not a single driver with such a control in the linux kernel) can be + * queried from the sensor. This function shall provide that fixed, known value. + * + * \return The black level of the sensor, or std::nullopt if not known + */ + /** * \brief Compute gain code from the analogue gain absolute value * \param[in] gain The real gain to pass @@ -396,6 +420,7 @@ class CameraSensorHelperImx219 : public CameraSensorHelper public: CameraSensorHelperImx219() { + blackLevel_ = 4096; gainType_ = AnalogueGainLinear; gainConstants_.linear = { 0, 256, -1, 256 }; } @@ -407,6 +432,7 @@ class CameraSensorHelperImx258 : public CameraSensorHelper public: CameraSensorHelperImx258() { + blackLevel_ = 4096; gainType_ = AnalogueGainLinear; gainConstants_.linear = { 0, 512, -1, 512 }; } @@ -456,6 +482,7 @@ class CameraSensorHelperImx335 : public CameraSensorHelper public: CameraSensorHelperImx335() { + blackLevel_ = 3200; gainType_ = AnalogueGainExponential; gainConstants_.exp = { 1.0, expGainDb(0.3) }; } diff --git a/src/ipa/libipa/camera_sensor_helper.h b/src/ipa/libipa/camera_sensor_helper.h index 0d99073bea82..ac276e27f523 100644 --- a/src/ipa/libipa/camera_sensor_helper.h +++ b/src/ipa/libipa/camera_sensor_helper.h @@ -10,6 +10,7 @@ #include #include +#include #include #include @@ -25,6 +26,7 @@ public: CameraSensorHelper() = default; virtual ~CameraSensorHelper() = default; + std::optional blackLevel() const { return blackLevel_; } virtual uint32_t gainCode(double gain) const; virtual double gain(uint32_t gainCode) const; @@ -51,6 +53,7 @@ protected: AnalogueGainExpConstants exp; }; + std::optional blackLevel_; AnalogueGainType gainType_; AnalogueGainConstants gainConstants_;