{"id":22796,"url":"https://patchwork.libcamera.org/api/patches/22796/?format=json","web_url":"https://patchwork.libcamera.org/patch/22796/","project":{"id":1,"url":"https://patchwork.libcamera.org/api/projects/1/?format=json","name":"libcamera","link_name":"libcamera","list_id":"libcamera_core","list_email":"libcamera-devel@lists.libcamera.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20250217100203.297894-11-stefan.klug@ideasonboard.com>","date":"2025-02-17T10:01:51","name":"[10/10] ipa: rkisp1: awb: Avoid division by zero","commit_ref":null,"pull_url":null,"state":"superseded","archived":false,"hash":"dc6119c16dbffdaa7e71be71c02c738b97b9cea8","submitter":{"id":184,"url":"https://patchwork.libcamera.org/api/people/184/?format=json","name":"Stefan Klug","email":"stefan.klug@ideasonboard.com"},"delegate":null,"mbox":"https://patchwork.libcamera.org/patch/22796/mbox/","series":[{"id":5005,"url":"https://patchwork.libcamera.org/api/series/5005/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=5005","date":"2025-02-17T10:01:41","name":"Some rkisp1 awb improvements","version":1,"mbox":"https://patchwork.libcamera.org/series/5005/mbox/"}],"comments":"https://patchwork.libcamera.org/api/patches/22796/comments/","check":"pending","checks":"https://patchwork.libcamera.org/api/patches/22796/checks/","tags":{},"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 04C55C32A2\n\tfor ;\n\tMon, 17 Feb 2025 10:02:40 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 92AC168683;\n\tMon, 17 Feb 2025 11:02:39 +0100 (CET)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 588A56867B\n\tfor ;\n\tMon, 17 Feb 2025 11:02:36 +0100 (CET)","from ideasonboard.com (unknown\n\t[IPv6:2a00:6020:448c:6c00:b47f:e20a:c4c7:ece1])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 07F8D11E9;\n\tMon, 17 Feb 2025 11:01:14 +0100 (CET)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"t7UU0c9y\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1739786475;\n\tbh=W1dgfgNDzGkCyu/+G5U/h/Hyu964ZmBC5f9BvphT/Ss=;\n\th=From:To:Cc:Subject:Date:In-Reply-To:References:From;\n\tb=t7UU0c9y+yAWABi0teAkk4sQnnoBsFK5IXmn7tAKZQT8Tyq31fS77MOn2I3QTuMTY\n\tJJuA0RdJkKBOi6PB/b7oIZS05Ai11XobBieQYrbmbda6wDlIxdNtBVHre62a8Xicd/\n\tA1AuQ8xcT3B3508TlEAvBhvp0EZxtKKiPSp2q2Hg=","From":"Stefan Klug ","To":"libcamera-devel@lists.libcamera.org","Cc":"Stefan Klug ","Subject":"[PATCH 10/10] ipa: rkisp1: awb: Avoid division by zero","Date":"Mon, 17 Feb 2025 11:01:51 +0100","Message-ID":"<20250217100203.297894-11-stefan.klug@ideasonboard.com>","X-Mailer":"git-send-email 2.43.0","In-Reply-To":"<20250217100203.297894-1-stefan.klug@ideasonboard.com>","References":"<20250217100203.297894-1-stefan.klug@ideasonboard.com>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","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\" "},"content":"As the gains can also be specified manually, the regulation can run\ninto numeric instabilities by dividing by near zero. Mitigate that by applying a small minium value.\n\nSigned-off-by: Stefan Klug \n---\n src/ipa/rkisp1/algorithms/awb.cpp | 4 ++--\n 1 file changed, 2 insertions(+), 2 deletions(-)","diff":"diff --git a/src/ipa/rkisp1/algorithms/awb.cpp b/src/ipa/rkisp1/algorithms/awb.cpp\nindex 66e6aecedc4c..6315d2adaad9 100644\n--- a/src/ipa/rkisp1/algorithms/awb.cpp\n+++ b/src/ipa/rkisp1/algorithms/awb.cpp\n@@ -310,9 +310,9 @@ void Awb::process(IPAContext &context,\n \t/*\n \t * The ISP computes the AWB means after applying the colour gains,\n \t * divide by the gains that were used to get the raw means from the\n-\t * sensor.\n+\t * sensor. Apply a minimum value to avoid divisions by near-zero.\n \t */\n-\trgbMeans /= frameContext.awb.gains;\n+\trgbMeans /= frameContext.awb.gains.max(0.01);\n \n \t/*\n \t * If the means are too small we don't have enough information to\n","prefixes":["10/10"]}