{"id":23132,"url":"https://patchwork.libcamera.org/api/1.1/patches/23132/?format=json","web_url":"https://patchwork.libcamera.org/patch/23132/","project":{"id":1,"url":"https://patchwork.libcamera.org/api/1.1/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":"<20250403154925.382973-17-stefan.klug@ideasonboard.com>","date":"2025-04-03T15:49:21","name":"[v3,16/16] ipa: rkisp1: awb: Avoid division by zero","commit_ref":null,"pull_url":null,"state":"accepted","archived":false,"hash":"ce34306809ab0fa6a84215924007d5ffcb30cc15","submitter":{"id":184,"url":"https://patchwork.libcamera.org/api/1.1/people/184/?format=json","name":"Stefan Klug","email":"stefan.klug@ideasonboard.com"},"delegate":null,"mbox":"https://patchwork.libcamera.org/patch/23132/mbox/","series":[{"id":5111,"url":"https://patchwork.libcamera.org/api/1.1/series/5111/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=5111","date":"2025-04-03T15:49:05","name":"Some rkisp1 awb improvements","version":3,"mbox":"https://patchwork.libcamera.org/series/5111/mbox/"}],"comments":"https://patchwork.libcamera.org/api/patches/23132/comments/","check":"pending","checks":"https://patchwork.libcamera.org/api/patches/23132/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 092F0C327D\n\tfor ;\n\tThu, 3 Apr 2025 15:50:25 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id B8D5368AB7;\n\tThu, 3 Apr 2025 17:50:24 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id CAAF268AB5\n\tfor ;\n\tThu, 3 Apr 2025 17:50:22 +0200 (CEST)","from ideasonboard.com (unknown\n\t[IPv6:2a00:6020:448c:6c00:6d9d:9854:3fc1:4bb2])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 22A7F1624;\n\tThu, 3 Apr 2025 17:48:29 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"X7vsoyFA\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1743695309;\n\tbh=kQ2fDfNpxKxYjPice0bjRindnmwA0nJ8zzwa8VIAV4w=;\n\th=From:To:Cc:Subject:Date:In-Reply-To:References:From;\n\tb=X7vsoyFANVJHc1BXsOT+ZA/txtmTuM9U2U9rynLwP9mlOMZxv1YOOLclhxhU3P3Jj\n\t0N4PQHrV9y4oW47gETH7Mbl9zk6eL6Ry0EW6ANYFPfL0HqwHbijL4OHUg8n7ngwjne\n\tVm/WN2xa1gh7Lnpvtujpuh2Z3xD/2Tf7eRTnJZEY=","From":"Stefan Klug ","To":"libcamera-devel@lists.libcamera.org","Cc":"Stefan Klug ,\n\tKieran Bingham ","Subject":"[PATCH v3 16/16] ipa: rkisp1: awb: Avoid division by zero","Date":"Thu, 3 Apr 2025 17:49:21 +0200","Message-ID":"<20250403154925.382973-17-stefan.klug@ideasonboard.com>","X-Mailer":"git-send-email 2.43.0","In-Reply-To":"<20250403154925.382973-1-stefan.klug@ideasonboard.com>","References":"<20250403154925.382973-1-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 into\nnumeric instabilities by dividing by near zero. Mitigate that by\napplying a small minium value.\n\nSigned-off-by: Stefan Klug \nReviewed-by: Kieran Bingham \n\n---\n\nChanges in v2:\n- Collected tag\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 03449e87e1a0..84aa1d29419d 100644\n--- a/src/ipa/rkisp1/algorithms/awb.cpp\n+++ b/src/ipa/rkisp1/algorithms/awb.cpp\n@@ -406,9 +406,9 @@ RGB Awb::calculateRgbMeans(const IPAFrameContext &frameContext, const rk\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 \treturn rgbMeans;\n }\n","prefixes":["v3","16/16"]}