From patchwork Fri Aug 15 10:29:30 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Klug X-Patchwork-Id: 24120 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 01659BDCC1 for ; Fri, 15 Aug 2025 10:30:25 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id B0F606926D; Fri, 15 Aug 2025 12:30:24 +0200 (CEST) Authentication-Results: lancelot.ideasonboard.com; dkim=pass (1024-bit key; unprotected) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="QeGGocTR"; dkim-atps=neutral Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id D454469257 for ; Fri, 15 Aug 2025 12:30:22 +0200 (CEST) Received: from ideasonboard.com (unknown [IPv6:2a00:6020:448c:6c00:83d1:ae5d:93a6:6837]) by perceval.ideasonboard.com (Postfix) with UTF8SMTPSA id F1E0263B; Fri, 15 Aug 2025 12:29:27 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1755253768; bh=nKYdeg/rjPmxtrIhnHWZjQwl6Bu8ytOiSVuUnZZfJoI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QeGGocTRNp8mHFMry8AggnO8Jtgnisli3g3NQMUb3I8O7j6FgZAugJ3ZBFDNo9wPk PxJEMe3KLWzJThQj8SoS+iPK5r7vHW1/NKDYm0KvfN98avKCRZUdNqcshCnKeUwT1L zjQUbqp+4gSwCjekMw8NkP36vpH1w51mDEnRe/xY= From: Stefan Klug To: libcamera-devel@lists.libcamera.org Cc: Stefan Klug , Kieran Bingham , Daniel Scally Subject: [PATCH v3 10/19] ipa: rkisp1: agc: Add correction for exposure quantization Date: Fri, 15 Aug 2025 12:29:30 +0200 Message-ID: <20250815102945.1602071-11-stefan.klug@ideasonboard.com> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250815102945.1602071-1-stefan.klug@ideasonboard.com> References: <20250815102945.1602071-1-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" There are several occations where quantization can lead to visible effects. In WDR mode it can happen that exposure times get set to very low values (Sometimes 2-3 lines). This intentionally introduced underexposure is corrected by the GWDR module. As exposure time is quantized by lines, the smallest possible change in exposure time now results in a quite visible change in perceived brightness. Sometimes the possible gain steps are also quite large leading to visible jumps if e.g. if the exposure time is fixed. Mitigate that by applying a global gain to account for the error introduced by the exposure quantization. ToDo: This needs perfect frame synchronous control of the sensor to work properly which is not guaranteed in all cases. It still improves the behavior with the current regulation and can easily be skipped, when there is no compress algorithm. Signed-off-by: Stefan Klug Reviewed-by: Kieran Bingham Reviewed-by: Daniel Scally Reviewed-by: Paul Elder --- Changes in v3: - Collected tags --- src/ipa/rkisp1/algorithms/agc.cpp | 24 +++++++++++++++++++++--- src/ipa/rkisp1/ipa_context.h | 2 ++ 2 files changed, 23 insertions(+), 3 deletions(-) diff --git a/src/ipa/rkisp1/algorithms/agc.cpp b/src/ipa/rkisp1/algorithms/agc.cpp index 0a29326841fb..d34c041f9fe1 100644 --- a/src/ipa/rkisp1/algorithms/agc.cpp +++ b/src/ipa/rkisp1/algorithms/agc.cpp @@ -199,6 +199,9 @@ int Agc::configure(IPAContext &context, const IPACameraSensorInfo &configInfo) context.configuration.agc.measureWindow.h_size = configInfo.outputSize.width; context.configuration.agc.measureWindow.v_size = configInfo.outputSize.height; + AgcMeanLuminance::configure(context.configuration.sensor.lineDuration, + context.camHelper.get()); + setLimits(context.configuration.sensor.minExposureTime, context.configuration.sensor.maxExposureTime, context.configuration.sensor.minAnalogueGain, @@ -283,6 +286,10 @@ void Agc::queueRequest(IPAContext &context, if (!frameContext.agc.autoGainEnabled) frameContext.agc.gain = agc.manual.gain; + if (!frameContext.agc.autoExposureEnabled && + !frameContext.agc.autoGainEnabled) + frameContext.agc.quantizationGain = 1.0; + const auto &meteringMode = controls.get(controls::AeMeteringMode); if (meteringMode) { frameContext.agc.updateMetering = agc.meteringMode != *meteringMode; @@ -336,12 +343,17 @@ void Agc::prepare(IPAContext &context, const uint32_t frame, { uint32_t activeAutoExposure = context.activeState.agc.automatic.exposure; double activeAutoGain = context.activeState.agc.automatic.gain; + double activeAutoQGain = context.activeState.agc.automatic.quantizationGain; /* Populate exposure and gain in auto mode */ - if (frameContext.agc.autoExposureEnabled) + if (frameContext.agc.autoExposureEnabled) { frameContext.agc.exposure = activeAutoExposure; - if (frameContext.agc.autoGainEnabled) + frameContext.agc.quantizationGain = activeAutoQGain; + } + if (frameContext.agc.autoGainEnabled) { frameContext.agc.gain = activeAutoGain; + frameContext.agc.quantizationGain = activeAutoQGain; + } /* * Populate manual exposure and gain from the active auto values when @@ -354,6 +366,12 @@ void Agc::prepare(IPAContext &context, const uint32_t frame, if (!frameContext.agc.autoGainEnabled && frameContext.agc.autoGainModeChange) { context.activeState.agc.manual.gain = activeAutoGain; frameContext.agc.gain = activeAutoGain; + frameContext.agc.quantizationGain = activeAutoQGain; + } + + if (context.activeState.compress.supported) { + frameContext.compress.enable = true; + frameContext.compress.gain = frameContext.agc.quantizationGain; } if (frame > 0 && !frameContext.agc.updateMetering) @@ -582,7 +600,7 @@ void Agc::process(IPAContext &context, [[maybe_unused]] const uint32_t frame, /* Update the estimated exposure and gain. */ activeState.agc.automatic.exposure = newExposureTime / lineDuration; activeState.agc.automatic.gain = aGain; - + activeState.agc.automatic.quantizationGain = qGain; /* * Expand the target frame duration so that we do not run faster than * the minimum frame duration when we have short exposures. diff --git a/src/ipa/rkisp1/ipa_context.h b/src/ipa/rkisp1/ipa_context.h index 37a74215ce19..362ab2fda5fe 100644 --- a/src/ipa/rkisp1/ipa_context.h +++ b/src/ipa/rkisp1/ipa_context.h @@ -77,6 +77,7 @@ struct IPAActiveState { struct { uint32_t exposure; double gain; + double quantizationGain; } automatic; bool autoExposureEnabled; @@ -135,6 +136,7 @@ struct IPAFrameContext : public FrameContext { uint32_t exposure; double gain; double exposureValue; + double quantizationGain; uint32_t vblank; bool autoExposureEnabled; bool autoGainEnabled;