[{"id":37250,"web_url":"https://patchwork.libcamera.org/comment/37250/","msgid":"<858qfa5st7.fsf@mzamazal-thinkpadp1gen7.tpbc.csb>","date":"2025-12-10T14:12:52","subject":"Re: [PATCH v7 09/26] libcamera: shaders: Add support for Gamma","submitter":{"id":177,"url":"https://patchwork.libcamera.org/api/people/177/","name":"Milan Zamazal","email":"mzamazal@redhat.com"},"content":"Bryan O'Donoghue writes:\n\n> Add gamma compensation to the debayer shaders after colour correction is\n> applied.\n>\n> Similarly only apply the calculated Gamma curve when using the CCM as the\n> lookup tables already contain the data.\n>\n> Suggested-by: Milan Zamazal \n> Signed-off-by: Bryan O'Donoghue \n\nReviewed-by: Milan Zamazal \n\n> ---\n> src/libcamera/shaders/bayer_1x_packed.frag | 4 ++++\n> src/libcamera/shaders/bayer_unpacked.frag | 4 ++++\n> 2 files changed, 8 insertions(+)\n>\n> diff --git a/src/libcamera/shaders/bayer_1x_packed.frag b/src/libcamera/shaders/bayer_1x_packed.frag\n> index 7036fe278..77d9fbfa7 100644\n> --- a/src/libcamera/shaders/bayer_1x_packed.frag\n> +++ b/src/libcamera/shaders/bayer_1x_packed.frag\n> @@ -67,6 +67,7 @@ uniform vec2 tex_bayer_first_red;\n> uniform sampler2D tex_y;\n> uniform mat3 ccm;\n> uniform vec3 blacklevel;\n> +uniform float gamma;\n> \n> void main(void)\n> {\n> @@ -260,6 +261,9 @@ void main(void)\n> \trgb.g = (rin * ccm[1][0]) + (gin * ccm[1][1]) + (bin * ccm[1][2]);\n> \trgb.b = (rin * ccm[2][0]) + (gin * ccm[2][1]) + (bin * ccm[2][2]);\n> \n> +\t/* Apply gamma after colour correction */\n> +\trgb = pow(rgb, vec3(gamma));\n> +\n> #if defined (SWAP_BLUE)\n> \tgl_FragColor = vec4(rgb.bgr, 1.0);\n> #else\n> diff --git a/src/libcamera/shaders/bayer_unpacked.frag b/src/libcamera/shaders/bayer_unpacked.frag\n> index f0d8cd1e2..aba11a87f 100644\n> --- a/src/libcamera/shaders/bayer_unpacked.frag\n> +++ b/src/libcamera/shaders/bayer_unpacked.frag\n> @@ -26,6 +26,7 @@ varying vec4 yCoord;\n> varying vec4 xCoord;\n> uniform mat3 ccm;\n> uniform vec3 blacklevel;\n> +uniform float gamma;\n> \n> void main(void) {\n> vec3 rgb;\n> @@ -155,6 +156,9 @@ void main(void) {\n> rgb.g = (rin * ccm[1][0]) + (gin * ccm[1][1]) + (bin * ccm[1][2]);\n> rgb.b = (rin * ccm[2][0]) + (gin * ccm[2][1]) + (bin * ccm[2][2]);\n> \n> + /* Apply gamma after colour correction */\n> + rgb = pow(rgb, vec3(gamma));\n> +\n> #if defined (SWAP_BLUE)\n> gl_FragColor = vec4(rgb.bgr, 1.0);\n> #else","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 C11FEC3257\n\tfor ;\n\tWed, 10 Dec 2025 14:12:59 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 73AD661480;\n\tWed, 10 Dec 2025 15:12:59 +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 2EE5A613CB\n\tfor ;\n\tWed, 10 Dec 2025 15:12:58 +0100 (CET)","from mail-wm1-f72.google.com (mail-wm1-f72.google.com\n\t[209.85.128.72]) by relay.mimecast.com with ESMTP with STARTTLS\n\t(version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id\n\tus-mta-39-KOb-iro_PgCZVFux-F38qw-1; 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\n\tWed, 10 Dec 2025 06:12:54 -0800 (PST)","by 2002:a05:600c:860b:b0:477:8b77:155e with SMTP id\n\t5b1f17b1804b1-47a8380c69amr29470195e9.15.1765375973792; \n\tWed, 10 Dec 2025 06:12:53 -0800 (PST)"],"X-Google-Smtp-Source":"AGHT+IHNYejanPyAec4J6gnZlLgIT7a8Qymtt4zT9RJ+07W6VargnPW8OTK1GrlQF4B4o/9IgbFysQ==","From":"Milan Zamazal ","To":"Bryan O'Donoghue ","Cc":"libcamera-devel@lists.libcamera.org, pavel@ucw.cz","Subject":"Re: [PATCH v7 09/26] libcamera: shaders: Add support for Gamma","In-Reply-To":"<20251210005354.44726-10-bryan.odonoghue@linaro.org> (Bryan\n\tO'Donoghue's message of \"Wed, 10 Dec 2025 00:53:37 +0000\")","References":"<20251210005354.44726-1-bryan.odonoghue@linaro.org>\n\t<20251210005354.44726-10-bryan.odonoghue@linaro.org>","Date":"Wed, 10 Dec 2025 15:12:52 +0100","Message-ID":"<858qfa5st7.fsf@mzamazal-thinkpadp1gen7.tpbc.csb>","User-Agent":"Gnus/5.13 (Gnus v5.13)","MIME-Version":"1.0","X-Mimecast-Spam-Score":"0","X-Mimecast-MFC-PROC-ID":"DHXMwduixhdGWYbiW8BorXjtVaeegCJ77bCPDueVDrU_1765375974","X-Mimecast-Originator":"redhat.com","Content-Type":"text/plain","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\" "}}]