From patchwork Fri May 31 12:38:37 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Milan Zamazal X-Patchwork-Id: 20171 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 8C8C9BDE6B for ; Fri, 31 May 2024 12:39:04 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id 34DBC634BC; Fri, 31 May 2024 14:39:04 +0200 (CEST) Authentication-Results: lancelot.ideasonboard.com; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.b="bQcxwxWO"; dkim-atps=neutral Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id B4A59634AF for ; Fri, 31 May 2024 14:39:01 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1717159140; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=tmp8x2JElBY+1aZMMPEis5CdFwhlbaspITWXBXWrkXk=; b=bQcxwxWOpibSk9ho2xvyAniPhRXMcV6XottGva6D+ms4FYfAKHipPLcndd4lN19O+h7wKb P/Gqo43UepeMrdn9CrLsgoRvBDmBhqMH8ctSZaxqt6IDRFnPplmNu02famDeIen4xCq24u j7YgEifk6fEZyQ47qH9GaUpnnlCCC/Q= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-206-URmQWt2HPBeAVp_lux9RWA-1; Fri, 31 May 2024 08:38:59 -0400 X-MC-Unique: URmQWt2HPBeAVp_lux9RWA-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id E970C185A780; Fri, 31 May 2024 12:38:58 +0000 (UTC) Received: from nuthatch.redhat.com (unknown [10.45.225.166]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8F5BAC15BB1; Fri, 31 May 2024 12:38:57 +0000 (UTC) From: Milan Zamazal To: libcamera-devel@lists.libcamera.org Cc: Milan Zamazal , Kieran Bingham , Andrei Konovalov , Laurent Pinchart Subject: [PATCH v6 2/5] libcamera: software_isp: Honor black level in AWB Date: Fri, 31 May 2024 14:38:37 +0200 Message-ID: <20240531123840.713364-3-mzamazal@redhat.com> In-Reply-To: <20240531123840.713364-1-mzamazal@redhat.com> References: <20240531123840.713364-1-mzamazal@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.8 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com 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" The white balance computation didn't consider black level. This is wrong because then the computed ratios are off when they are computed from the whole brightness range rather than the sensor range. This patch adjusts white balance computation for the black level. There is no need to change white balance application in debayering as this is already applied after black level correction. Exposure computation already subtracts black level, no changes are needed there. Signed-off-by: Milan Zamazal Reviewed-by: Andrei Konovalov Reviewed-by: Laurent Pinchart --- src/ipa/simple/soft_simple.cpp | 35 +++++++++++++++++++++------------- 1 file changed, 22 insertions(+), 13 deletions(-) diff --git a/src/ipa/simple/soft_simple.cpp b/src/ipa/simple/soft_simple.cpp index a5bb2bbf..f383f994 100644 --- a/src/ipa/simple/soft_simple.cpp +++ b/src/ipa/simple/soft_simple.cpp @@ -5,6 +5,8 @@ * Simple Software Image Processing Algorithm module */ +#include +#include #include #include @@ -240,28 +242,35 @@ void IPASoftSimple::stop() void IPASoftSimple::processStats(const ControlList &sensorControls) { + SwIspStats::Histogram histogram = stats_->yHistogram; + if (ignoreUpdates_ > 0) + blackLevel_.update(histogram); + const uint8_t blackLevel = blackLevel_.get(); + params_->blackLevel = blackLevel; + + /* + * Black level must be subtracted to get the correct AWB ratios, + * they would be off if they were computed from the whole brightness + * range rather than from the sensor range. + */ + const uint64_t nPixels = std::accumulate( + histogram.begin(), histogram.end(), 0); + const uint64_t offset = blackLevel * nPixels; + const uint64_t sumR = stats_->sumR_ - offset / 4; + const uint64_t sumG = stats_->sumG_ - offset / 2; + const uint64_t sumB = stats_->sumB_ - offset / 4; + /* * Calculate red and blue gains for AWB. * Clamp max gain at 4.0, this also avoids 0 division. */ - if (stats_->sumR_ <= stats_->sumG_ / 4) - params_->gainR = 1024; - else - params_->gainR = 256 * stats_->sumG_ / stats_->sumR_; - - if (stats_->sumB_ <= stats_->sumG_ / 4) - params_->gainB = 1024; - else - params_->gainB = 256 * stats_->sumG_ / stats_->sumB_; + params_->gainR = sumR <= sumG / 4 ? 1024 : 256 * sumG / sumR; + params_->gainB = sumB <= sumG / 4 ? 1024 : 256 * sumG / sumB; /* Green gain and gamma values are fixed */ params_->gainG = 256; params_->gamma = 0.5; - if (ignoreUpdates_ > 0) - blackLevel_.update(stats_->yHistogram); - params_->blackLevel = blackLevel_.get(); - setIspParams.emit(); /* \todo Switch to the libipa/algorithm.h API someday. */