{"id":25645,"url":"https://patchwork.libcamera.org/api/1.1/patches/25645/?format=json","web_url":"https://patchwork.libcamera.org/patch/25645/","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":"<20260106165754.1759831-16-barnabas.pocze@ideasonboard.com>","date":"2026-01-06T16:57:47","name":"[v4,15/22] guides: application: Document Camera::metadataAvailable","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"d484b69065c72c293520783d0f4226dc14525552","submitter":{"id":216,"url":"https://patchwork.libcamera.org/api/1.1/people/216/?format=json","name":"Barnabás Pőcze","email":"barnabas.pocze@ideasonboard.com"},"delegate":null,"mbox":"https://patchwork.libcamera.org/patch/25645/mbox/","series":[{"id":5688,"url":"https://patchwork.libcamera.org/api/1.1/series/5688/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=5688","date":"2026-01-06T16:57:32","name":"libcamera: Add `MetadataList`","version":4,"mbox":"https://patchwork.libcamera.org/series/5688/mbox/"}],"comments":"https://patchwork.libcamera.org/api/patches/25645/comments/","check":"pending","checks":"https://patchwork.libcamera.org/api/patches/25645/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 2BA07C32AF\n\tfor ;\n\tTue, 6 Jan 2026 16:58:19 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 4798461FD3;\n\tTue, 6 Jan 2026 17:58:14 +0100 (CET)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id B9C1D61FC9\n\tfor ;\n\tTue, 6 Jan 2026 17:58:01 +0100 (CET)","from pb-laptop.local (185.221.143.114.nat.pool.zt.hu\n\t[185.221.143.114])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id AB5A91AAE;\n\tTue, 6 Jan 2026 17:57:40 +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=\"c0VD5JTJ\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1767718660;\n\tbh=feYXSQdNRDE377ftRoz1dXJzRqiPbSFTQ4/oH38D3f0=;\n\th=From:To:Cc:Subject:Date:In-Reply-To:References:From;\n\tb=c0VD5JTJokRnF5zVKg++0Kd1hREZPR4bM2EKWWkv98/Di5xJ0OXCRiqI/O1lpQVU+\n\tkRL66SVJy9XCqeeXwY2dsQB1DdMWdwjzshthALdS0LvOGArHdFF0baixgYaggNezuj\n\t1LbEBKvgO+wgM0lanwZe0Vtgi9zugvez0TZksqbs=","From":"=?utf-8?q?Barnab=C3=A1s_P=C5=91cze?= ","To":"libcamera-devel@lists.libcamera.org","Cc":"Jacopo Mondi ,\n\tKieran Bingham ","Subject":"[PATCH v4 15/22] guides: application: Document\n\tCamera::metadataAvailable","Date":"Tue, 6 Jan 2026 17:57:47 +0100","Message-ID":"<20260106165754.1759831-16-barnabas.pocze@ideasonboard.com>","X-Mailer":"git-send-email 2.52.0","In-Reply-To":"<20260106165754.1759831-1-barnabas.pocze@ideasonboard.com>","References":"<20260106165754.1759831-1-barnabas.pocze@ideasonboard.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=UTF-8","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":"From: Jacopo Mondi \n\nDocument the Camera::metadataAvailable signal in the application\ndeveloper guide as an opt-in feature to receive early metadata\nnotifications.\n\nSigned-off-by: Jacopo Mondi \nSigned-off-by: Barnabás Pőcze \nReviewed-by: Kieran Bingham \n---\nOriginal: https://patchwork.libcamera.org/patch/22228/\n\nchanges in v3:\n * adjust previous paragraph about signals\n---\n Documentation/guides/application-developer.rst | 13 +++++++++++--\n 1 file changed, 11 insertions(+), 2 deletions(-)","diff":"diff --git a/Documentation/guides/application-developer.rst b/Documentation/guides/application-developer.rst\nindex 06c07d1e9..344c2a6df 100644\n--- a/Documentation/guides/application-developer.rst\n+++ b/Documentation/guides/application-developer.rst\n@@ -350,8 +350,17 @@ them.\n \n .. _Qt Signals and Slots: https://doc.qt.io/qt-6/signalsandslots.html\n \n-The ``Camera`` device emits two signals that applications can connect to in\n-order to execute callbacks on frame completion events.\n+During request processing, the ``Camera`` device emits certain signals\n+to notify the application about events regarding each and every request.\n+These signals are described below.\n+\n+The ``Camera::metadataAvailable`` signal notifies applications of the\n+availability of metadata results before a request completes. Receiving\n+notification about metadata availability enables applications to fast-track\n+handling of metadata results before all the image buffers in a request are\n+ready. The full list of metadata results associated with a Request is also\n+available at request complete time, and receiving notifications for early\n+metadata availability is an optional feature for applications.\n \n The ``Camera::bufferCompleted`` signal notifies applications that a buffer with\n image data is available. Receiving notifications about the single buffer\n","prefixes":["v4","15/22"]}