[{"id":37510,"web_url":"https://patchwork.libcamera.org/comment/37510/","msgid":"<176778491537.3486172.4892029100460149427@ping.linuxembedded.co.uk>","date":"2026-01-07T11:21:55","subject":"Re: [PATCH v11 09/24] libcamera: shaders: Add support for black\n\tlevel compensation","submitter":{"id":4,"url":"https://patchwork.libcamera.org/api/people/4/","name":"Kieran Bingham","email":"kieran.bingham@ideasonboard.com"},"content":"Quoting Bryan O'Donoghue (2026-01-06 17:00:44)\n> Add the ability to apply a int blacklevel gain against the demosaiced data\n\nExcept that it's a 'blacklevel subtraction' not a 'blacklevel gain'\n(which I can fix when applying)\n\nReviewed-by: Kieran Bingham \n\n> prior to application of colour correction data.\n> \n> Reviewed-by: Milan Zamazal \n> Signed-off-by: Bryan O'Donoghue \n> ---\n> src/libcamera/shaders/bayer_1x_packed.frag | 3 +++\n> src/libcamera/shaders/bayer_unpacked.frag | 3 +++\n> 2 files changed, 6 insertions(+)\n> \n> diff --git a/src/libcamera/shaders/bayer_1x_packed.frag b/src/libcamera/shaders/bayer_1x_packed.frag\n> index db8c2a0b3..7036fe278 100644\n> --- a/src/libcamera/shaders/bayer_1x_packed.frag\n> +++ b/src/libcamera/shaders/bayer_1x_packed.frag\n> @@ -66,6 +66,7 @@ uniform vec2 tex_bayer_first_red;\n> \n> uniform sampler2D tex_y;\n> uniform mat3 ccm;\n> +uniform vec3 blacklevel;\n> \n> void main(void)\n> {\n> @@ -213,6 +214,8 @@ void main(void)\n> vec3(patterns.y, C, patterns.x) :\n> vec3(patterns.wz, C));\n> \n> + rgb = rgb - blacklevel;\n> +\n> /*\n> * CCM is a 3x3 in the format\n> *\n> diff --git a/src/libcamera/shaders/bayer_unpacked.frag b/src/libcamera/shaders/bayer_unpacked.frag\n> index 06d80f3dd..f0d8cd1e2 100644\n> --- a/src/libcamera/shaders/bayer_unpacked.frag\n> +++ b/src/libcamera/shaders/bayer_unpacked.frag\n> @@ -25,6 +25,7 @@ varying vec4 center;\n> varying vec4 yCoord;\n> varying vec4 xCoord;\n> uniform mat3 ccm;\n> +uniform vec3 blacklevel;\n> \n> void main(void) {\n> vec3 rgb;\n> @@ -108,6 +109,8 @@ void main(void) {\n> vec3(PATTERN.w, C, PATTERN.z) :\n> vec3(PATTERN.yx, C));\n> \n> + rgb = rgb - blacklevel;\n> +\n> /*\n> * CCM is a 3x3 in the format\n> *\n> -- \n> 2.52.0\n>","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 73731BDCBF\n\tfor ;\n\tWed, 7 Jan 2026 11:22:01 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 6028761FBF;\n\tWed, 7 Jan 2026 12:22:00 +0100 (CET)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 8069261F84\n\tfor ;\n\tWed, 7 Jan 2026 12:21:58 +0100 (CET)","from pendragon.ideasonboard.com\n\t(cpc89244-aztw30-2-0-cust6594.18-1.cable.virginm.net [86.31.185.195])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id AC39B73B;\n\tWed, 7 Jan 2026 12:21:36 +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=\"DaJVNH+t\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1767784896;\n\tbh=YnlXYZTisJTgrp9jsZL9Rm/pvmu3TfzEgZcGaQtwtTc=;\n\th=In-Reply-To:References:Subject:From:Cc:To:Date:From;\n\tb=DaJVNH+tIA6Mk0DcyIR0iOugqA3LxJOu26hM5+krx0bRRnmobc+c3c6h46mR3kxPl\n\tPUk9MUav2DKOwOCC+Bq8rDvDjA2rr3d9z7qvZQLRZrA4hAAxyDKFvl2UpshMRzYRzX\n\tGmLc0HMOJTbzmJ/9ELb16nEfzFFbycQZSSAYXylU=","Content-Type":"text/plain; charset=\"utf-8\"","MIME-Version":"1.0","Content-Transfer-Encoding":"quoted-printable","In-Reply-To":"<20260106170059.56193-10-bryan.odonoghue@linaro.org>","References":"<20260106170059.56193-1-bryan.odonoghue@linaro.org>\n\t<20260106170059.56193-10-bryan.odonoghue@linaro.org>","Subject":"Re: [PATCH v11 09/24] libcamera: shaders: Add support for black\n\tlevel compensation","From":"Kieran Bingham ","Cc":"pavel@ucw.cz, Bryan O'Donoghue ,\n\tMilan Zamazal ","To":"Bryan O'Donoghue ,\n\tlibcamera-devel@lists.libcamera.org","Date":"Wed, 07 Jan 2026 11:21:55 +0000","Message-ID":"<176778491537.3486172.4892029100460149427@ping.linuxembedded.co.uk>","User-Agent":"alot/0.9.1","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\" "}}]