{"id":23623,"url":"https://patchwork.libcamera.org/api/patches/23623/?format=json","web_url":"https://patchwork.libcamera.org/patch/23623/","project":{"id":1,"url":"https://patchwork.libcamera.org/api/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":"<20250623081922.96900-1-barnabas.pocze@ideasonboard.com>","date":"2025-06-23T08:19:22","name":"[v1] libcamera: controls: Clarify units of `FrameWallClock`","commit_ref":null,"pull_url":null,"state":"superseded","archived":false,"hash":"945be1ab3190bfadb33deeb8f912843b41154bbe","submitter":{"id":216,"url":"https://patchwork.libcamera.org/api/people/216/?format=json","name":"Barnabás Pőcze","email":"barnabas.pocze@ideasonboard.com"},"delegate":null,"mbox":"https://patchwork.libcamera.org/patch/23623/mbox/","series":[{"id":5239,"url":"https://patchwork.libcamera.org/api/series/5239/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=5239","date":"2025-06-23T08:19:22","name":"[v1] libcamera: controls: Clarify units of `FrameWallClock`","version":1,"mbox":"https://patchwork.libcamera.org/series/5239/mbox/"}],"comments":"https://patchwork.libcamera.org/api/patches/23623/comments/","check":"pending","checks":"https://patchwork.libcamera.org/api/patches/23623/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 9AD56C3237\n\tfor ;\n\tMon, 23 Jun 2025 08:19:29 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id A740C68DE5;\n\tMon, 23 Jun 2025 10:19:28 +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 C415F61533\n\tfor ;\n\tMon, 23 Jun 2025 10:19:26 +0200 (CEST)","from pb-laptop.local (185.221.143.107.nat.pool.zt.hu\n\t[185.221.143.107])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 19BDED77;\n\tMon, 23 Jun 2025 10:19:10 +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=\"JxwoQ3Mo\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1750666750;\n\tbh=RTM2GRhF6kpTbiaBEF6o46PS5c5ERNWe+rvtJT7TwYs=;\n\th=From:To:Subject:Date:From;\n\tb=JxwoQ3MoK6tV6nMH5+w+6PM7sOVnzVMAgympPVUTMu9BNvzR+Xk+GzaiAOvhezs6p\n\tXlw/Ax2HKIyUKvfvXsen5WK7jac7LxF6CyW7Q75oqelVPXU8CDspwtTLxGYM1nH1UA\n\tRjjrtVh4W1LbFskb1ZSfIInH14sP6LePwjKfUC5M=","From":"=?utf-8?q?Barnab=C3=A1s_P=C5=91cze?= ","To":"libcamera-devel@lists.libcamera.org,\n\tDavid Plowman ,\n\tNaushir Patuck ","Subject":"[PATCH v1] libcamera: controls: Clarify units of `FrameWallClock`","Date":"Mon, 23 Jun 2025 10:19:22 +0200","Message-ID":"<20250623081922.96900-1-barnabas.pocze@ideasonboard.com>","X-Mailer":"git-send-email 2.50.0","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":"The description of the control mentions SensorTimestamp multiple\ntimes, but it omits that the two do not have the same units.\nClarify that.\n\nSigned-off-by: Barnabás Pőcze \n---\n\nOr could it easily be converted to nanoseconds? Is there an overflow issue\nin the ClockRecovery class in that case? What was the motivation for making\nit μs? (I suppose nanosecond resolution is not that useful when synchronizing\nacross a network, etc?)\n\n---\n src/libcamera/control_ids_core.yaml | 3 ++-\n 1 file changed, 2 insertions(+), 1 deletion(-)\n\n--\n2.50.0","diff":"diff --git a/src/libcamera/control_ids_core.yaml b/src/libcamera/control_ids_core.yaml\nindex 028919ef3..0708ec7cc 100644\n--- a/src/libcamera/control_ids_core.yaml\n+++ b/src/libcamera/control_ids_core.yaml\n@@ -1272,7 +1272,8 @@ controls:\n description: |\n This timestamp corresponds to the same moment in time as the\n SensorTimestamp, but is represented as a wall clock time as measured by\n- the CLOCK_REALTIME clock.\n+ the CLOCK_REALTIME clock. Note that this control measures time in units\n+ of microseconds as opposed to nanoseconds in case of SensorTimestamp.\n\n Being a wall clock measurement, it can be used to synchronise timing\n across different devices.\n","prefixes":["v1"]}