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{ "id": 26130, "url": "https://patchwork.libcamera.org/api/covers/26130/?format=api", "web_url": "https://patchwork.libcamera.org/cover/26130/", "project": { "id": 1, "url": "https://patchwork.libcamera.org/api/projects/1/?format=api", "name": "libcamera", "link_name": "libcamera", "list_id": "libcamera_core", "list_email": "libcamera-devel@lists.libcamera.org", "web_url": "", "scm_url": "", "webscm_url": "" }, "msgid": "<20260211131728.96413-1-mzamazal@redhat.com>", "date": "2026-02-11T13:17:26", "name": "[0/2] Fix black level handling in GPU ISP", "submitter": { "id": 177, "url": "https://patchwork.libcamera.org/api/people/177/?format=api", "name": "Milan Zamazal", "email": "mzamazal@redhat.com" }, "mbox": "https://patchwork.libcamera.org/cover/26130/mbox/", "series": [ { "id": 5784, "url": "https://patchwork.libcamera.org/api/series/5784/?format=api", "web_url": "https://patchwork.libcamera.org/project/libcamera/list/?series=5784", "date": "2026-02-11T13:17:26", "name": "Fix black level handling in GPU ISP", "version": 1, "mbox": "https://patchwork.libcamera.org/series/5784/mbox/" } ], "comments": "https://patchwork.libcamera.org/api/covers/26130/comments/", "headers": { "Return-Path": "<libcamera-devel-bounces@lists.libcamera.org>", "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 D735BBDE6B\n\tfor <parsemail@patchwork.libcamera.org>;\n\tWed, 11 Feb 2026 13:17:46 +0000 (UTC)", "from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id ECBE7621AB;\n\tWed, 11 Feb 2026 14:17:45 +0100 (CET)", "from us-smtp-delivery-124.mimecast.com\n\t(us-smtp-delivery-124.mimecast.com [170.10.129.124])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 59CB3620C9\n\tfor <libcamera-devel@lists.libcamera.org>;\n\tWed, 11 Feb 2026 14:17:44 +0100 (CET)", "from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com\n\t(ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63])\n\tby relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3,\n\tcipher=TLS_AES_256_GCM_SHA384) id us-mta-589-SRLWCMWePTicnR1yMkD2RQ-1;\n\tWed, 11 Feb 2026 08:17:39 -0500", "from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com\n\t(mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com\n\t[10.30.177.12])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\tkey-exchange X25519 server-signature RSA-PSS (2048 bits)\n\tserver-digest SHA256) (No client certificate requested)\n\tby mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix)\n\twith ESMTPS id 8C71C1956056; Wed, 11 Feb 2026 13:17:38 +0000 (UTC)", "from mzamazal-thinkpadp1gen7.tpbc.com (unknown [10.45.226.74])\n\tby mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix)\n\twith ESMTP id 825B019560A3; Wed, 11 Feb 2026 13:17:36 +0000 (UTC)" ], "Authentication-Results": "lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=redhat.com header.i=@redhat.com\n\theader.b=\"dqIQlFNQ\"; dkim-atps=neutral", "DKIM-Signature": "v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com;\n\ts=mimecast20190719; t=1770815863;\n\th=from:from:reply-to:subject:subject:date:date:message-id:message-id:\n\tto:to:cc:cc:mime-version:mime-version:content-type:content-type:\n\tcontent-transfer-encoding:content-transfer-encoding;\n\tbh=yEpTn/ox09RbEypypfNEs4L8Bf1Gb4n69pLptMJ8IJg=;\n\tb=dqIQlFNQQqYMaFPlcomI2vSn1MTfEsYUJAWxEomAcdisFFHwskM4j9Q1MYpL9K6MGAERAf\n\txbooVAknXiflnH70MBUMqOs/LIpnHjsu0ni4ZNcCdYXcKzJ1YcRvcXgq1mkvGSeyW2nj/i\n\tIMdELiVqTTWNOtK9TeUnvGuZ9pjregA=", "X-MC-Unique": "SRLWCMWePTicnR1yMkD2RQ-1", "X-Mimecast-MFC-AGG-ID": "SRLWCMWePTicnR1yMkD2RQ_1770815858", "From": "Milan Zamazal <mzamazal@redhat.com>", "To": "libcamera-devel@lists.libcamera.org", "Cc": "Milan Zamazal <mzamazal@redhat.com>,\n\tKieran Bingham <kieran.bingham@ideasonboard.com>,\n\tBryan O'Donoghue <bryan.odonoghue@linaro.org>", "Subject": "[PATCH 0/2] Fix black level handling in GPU ISP", "Date": "Wed, 11 Feb 2026 14:17:26 +0100", "Message-ID": "<20260211131728.96413-1-mzamazal@redhat.com>", "MIME-Version": "1.0", "X-Scanned-By": "MIMEDefang 3.0 on 10.30.177.12", "X-Mimecast-Spam-Score": "0", "X-Mimecast-MFC-PROC-ID": "N7jXeIccf4lPKnmQuhtu3aEX6wGlhHmrjrFg007naL0_1770815858", "X-Mimecast-Originator": "redhat.com", "Content-Transfer-Encoding": "8bit", "content-type": "text/plain; charset=\"US-ASCII\"; x-default=true", "X-BeenThere": "libcamera-devel@lists.libcamera.org", "X-Mailman-Version": "2.1.29", "Precedence": "list", "List-Id": "<libcamera-devel.lists.libcamera.org>", "List-Unsubscribe": "<https://lists.libcamera.org/options/libcamera-devel>,\n\t<mailto:libcamera-devel-request@lists.libcamera.org?subject=unsubscribe>", "List-Archive": "<https://lists.libcamera.org/pipermail/libcamera-devel/>", "List-Post": "<mailto:libcamera-devel@lists.libcamera.org>", "List-Help": "<mailto:libcamera-devel-request@lists.libcamera.org?subject=help>", "List-Subscribe": "<https://lists.libcamera.org/listinfo/libcamera-devel>,\n\t<mailto:libcamera-devel-request@lists.libcamera.org?subject=subscribe>", "Errors-To": "libcamera-devel-bounces@lists.libcamera.org", "Sender": "\"libcamera-devel\" <libcamera-devel-bounces@lists.libcamera.org>" }, "content": "There is an omission when applying black level in GPU ISP: the black\nlevel is subtracted but the resulting pixel values are not spread back\nto the whole 0..1 range. This prevents reaching maximum brightness with\nnon-zero black level and can also lead to pinkish bright areas or other\ncolour shifts.\n\nMilan Zamazal (2):\n ipa: simple: Limit the black level value\n libcamera: software_isp: Fix black level application in GPU ISP\n\n src/ipa/simple/algorithms/blc.cpp | 7 ++++---\n src/libcamera/shaders/bayer_1x_packed.frag | 2 +-\n src/libcamera/shaders/bayer_unpacked.frag | 2 +-\n 3 files changed, 6 insertions(+), 5 deletions(-)" }