From patchwork Tue Apr 30 17:34:27 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Milan Zamazal X-Patchwork-Id: 19969 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 6C0A3C3220 for ; Tue, 30 Apr 2024 17:34:59 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id 153C16341B; Tue, 30 Apr 2024 19:34:59 +0200 (CEST) Authentication-Results: lancelot.ideasonboard.com; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.b="bgzswFVK"; dkim-atps=neutral Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id E6B1A63415 for ; Tue, 30 Apr 2024 19:34:56 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1714498496; 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=C7GP/0/DF8Lmd5f5yLEVjIMYHES4hilTXexSX60y46o=; b=bgzswFVK2jx8vdmggtDoPU9vAWVCQMMy5t0kHVZhxfT+ggNRZeN+kCJGTUOOdKIG3KkWUe vYm/xeH8B78FqbrU3vkodythvkXqiAG7eL/hLw2E0pfe7VUFZ0XW4ZCaWChUsUZNNzly2M dCryESGazQYD/lgrcVyFyS+gY0lekBI= 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-501-anaKCHfEPquiJm3a0QuSgw-1; Tue, 30 Apr 2024 13:34:54 -0400 X-MC-Unique: anaKCHfEPquiJm3a0QuSgw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (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 10ED5182717E; Tue, 30 Apr 2024 17:34:54 +0000 (UTC) Received: from nuthatch.redhat.com (unknown [10.45.224.26]) by smtp.corp.redhat.com (Postfix) with ESMTP id 07EC51BDB2; Tue, 30 Apr 2024 17:34:52 +0000 (UTC) From: Milan Zamazal To: libcamera-devel@lists.libcamera.org Cc: Milan Zamazal , Laurent Pinchart Subject: [PATCH v2 2/5] libcamera: software_isp: Honor black level in AWB Date: Tue, 30 Apr 2024 19:34:27 +0200 Message-ID: <20240430173430.200392-3-mzamazal@redhat.com> In-Reply-To: <20240430173430.200392-1-mzamazal@redhat.com> References: <20240430173430.200392-1-mzamazal@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.5 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 --- src/ipa/simple/soft_simple.cpp | 36 ++++++++++++++++++++++------------ 1 file changed, 23 insertions(+), 13 deletions(-) diff --git a/src/ipa/simple/soft_simple.cpp b/src/ipa/simple/soft_simple.cpp index b9fb58b5..f595abc2 100644 --- a/src/ipa/simple/soft_simple.cpp +++ b/src/ipa/simple/soft_simple.cpp @@ -5,6 +5,8 @@ * soft_simple.cpp - Simple Software Image Processing Algorithm module */ +#include +#include #include #include @@ -240,28 +242,36 @@ 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; + /* * Calculate red and blue gains for AWB. * Clamp max gain at 4.0, this also avoids 0 division. + * Black level must be subtracted to get the correct AWB ratios, + * from the sensor range. */ - 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_; + const uint64_t nPixels = std::accumulate( + histogram.begin(), histogram.end(), 0); + auto subtractBlackLevel = [blackLevel, nPixels]( + uint64_t sum, uint64_t div) + -> uint64_t { + return sum - blackLevel * nPixels / div; + }; + const uint64_t sumR = subtractBlackLevel(stats_->sumR_, 4); + const uint64_t sumG = subtractBlackLevel(stats_->sumG_, 2); + const uint64_t sumB = subtractBlackLevel(stats_->sumB_, 4); + + 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. */