[{"id":26824,"web_url":"https://patchwork.libcamera.org/comment/26824/","msgid":"<20230404054659.GP16648@pendragon.ideasonboard.com>","date":"2023-04-04T05:46:59","subject":"Re: [libcamera-devel] [PATCH v3 0/2] Add flicker avoidance controls","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/people/2/","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"content":"Hi David,\n\nOn Tue, Mar 28, 2023 at 09:55:19AM +0100, David Plowman via libcamera-devel wrote:\n> Hi everyone\n> \n> Here's an updated version of flicker avoidance controls. It's similar\n> to what I had previously, except that I've split the control which\n> gave an explicit flicker period into two, one for reporting a\n> currently detected value, and another for setting a custom flicker\n> period. So we now have 3 controls in total.\n> \n> In terms of Android, the AeFlickerDetected control corresponds fairly\n> directly to Android's scene_flicker control, which is (from my reading\n> of it) merely reporting any currently detected flicker period.\n\nThat's my understanding too.\n\n> AeFlickerDetected, however, allows arbitrary flicker periods\n> to be identified, not just 50 or 60Hz.\n\nOut of curiosity, what are the use cases you envision for other\nfrequencies ?\n\n> The other controls (AeFlickerMode and AeFlickerCustom) correspond to\n> Android's anti-banding control. Again, we extend it to allow arbitrary\n> flicker periods.\n> \n> Hope that all makes sense!\n> \n> Thanks\n> David\n> \n> David Plowman (2):\n> libcamera: controls: Add controls for AEC/AGC flicker avoidance\n> ipa: raspberrypi: Handle AEC/AGC flicker controls\n> \n> src/ipa/raspberrypi/raspberrypi.cpp | 80 +++++++++++++++++++++++++++\n> src/libcamera/control_ids.yaml | 84 +++++++++++++++++++++++------\n> 2 files changed, 147 insertions(+), 17 deletions(-)","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 0BD2FC326B\n\tfor ;\n\tTue, 4 Apr 2023 05:46:56 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 2354F62724;\n\tTue, 4 Apr 2023 07:46:55 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 0C7EC603A4\n\tfor ;\n\tTue, 4 Apr 2023 07:46:53 +0200 (CEST)","from pendragon.ideasonboard.com (fp76f193f3.tkyc206.ap.nuro.jp\n\t[118.241.147.243])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 872E94A7;\n\tTue, 4 Apr 2023 07:46:51 +0200 (CEST)"],"DKIM-Signature":["v=1; a=rsa-sha256; c=relaxed/simple; d=libcamera.org;\n\ts=mail; t=1680587215;\n\tbh=tDl1xQzeah7Mcfqg+L8eGlyYp9Ih99qZbCB7NpybNl4=;\n\th=Date:To:References:In-Reply-To:Subject:List-Id:List-Unsubscribe:\n\tList-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc:\n\tFrom;\n\tb=jV3rgmVWuwMHVouYod6jymcS3Yss6u3w8ICsezsY2tv5LDryc9x2bP2sIo9jUXKf7\n\t4sr27QERBqYmiDrSPTTYnhPmSrDqPNbG50Yo3kQk9XJHxdyia6PVBhl0bs0d00v8w5\n\tndFbDCuF6cuRWP+ywX9D58oAVbRMKY9O89NGz9C81tdQuDfXUQiplzKrKHynWZxz8N\n\tnDUfWMLLYh83tLP7zFYwVpOvBby7P1ODWCqFk5cSECuL4/e0SjDWg/IY3EEjtG9hqh\n\t63/l70ZpJhr1qokntDb6iIb4hEOVEHN92Hazgo49CzJyk1w4QzhsprXsvHwKa5+N/T\n\t1JLFRytg24hKQ==","v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1680587212;\n\tbh=tDl1xQzeah7Mcfqg+L8eGlyYp9Ih99qZbCB7NpybNl4=;\n\th=Date:From:To:Cc:Subject:References:In-Reply-To:From;\n\tb=mnUT4fVtY6mdSXN1l0Ls0e8VgKMtfilvxIj9hqxizt/pKjcXPHDuwnkqMlIYuglyj\n\t/cfNdNiQ7H+kYfnEzLV1yFQnxDRqrtByndFKV2n2B/tbQzJxoNGGbCCcet5jWYRnN4\n\tVlVS+6Ja7+C/eKaQljqNXbxjM5NR9Hpc6tuEqBY0="],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key; \n\tunprotected) header.d=ideasonboard.com\n\theader.i=@ideasonboard.com\n\theader.b=\"mnUT4fVt\"; dkim-atps=neutral","Date":"Tue, 4 Apr 2023 08:46:59 +0300","To":"David Plowman ","Message-ID":"<20230404054659.GP16648@pendragon.ideasonboard.com>","References":"<20230328085521.7409-1-david.plowman@raspberrypi.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=utf-8","Content-Disposition":"inline","In-Reply-To":"<20230328085521.7409-1-david.plowman@raspberrypi.com>","Subject":"Re: [libcamera-devel] [PATCH v3 0/2] Add flicker avoidance controls","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","From":"Laurent Pinchart via libcamera-devel\n\t","Reply-To":"Laurent Pinchart ","Cc":"libcamera-devel@lists.libcamera.org","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "}},{"id":26834,"web_url":"https://patchwork.libcamera.org/comment/26834/","msgid":"","date":"2023-04-04T09:10:45","subject":"Re: [libcamera-devel] [PATCH v3 0/2] Add flicker avoidance controls","submitter":{"id":42,"url":"https://patchwork.libcamera.org/api/people/42/","name":"David Plowman","email":"david.plowman@raspberrypi.com"},"content":"Hi Laurent\n\nThanks for the questions!\n\nOn Tue, 4 Apr 2023 at 06:46, Laurent Pinchart\n wrote:\n>\n> Hi David,\n>\n> On Tue, Mar 28, 2023 at 09:55:19AM +0100, David Plowman via libcamera-devel wrote:\n> > Hi everyone\n> >\n> > Here's an updated version of flicker avoidance controls. It's similar\n> > to what I had previously, except that I've split the control which\n> > gave an explicit flicker period into two, one for reporting a\n> > currently detected value, and another for setting a custom flicker\n> > period. So we now have 3 controls in total.\n> >\n> > In terms of Android, the AeFlickerDetected control corresponds fairly\n> > directly to Android's scene_flicker control, which is (from my reading\n> > of it) merely reporting any currently detected flicker period.\n>\n> That's my understanding too.\n>\n> > AeFlickerDetected, however, allows arbitrary flicker periods\n> > to be identified, not just 50 or 60Hz.\n>\n> Out of curiosity, what are the use cases you envision for other\n> frequencies ?\n\nI think the most obvious use cases are when people have LEDs that run\nat other frequencies. Probably not such an issue for regular users,\nbut I could imagine it being useful in lab or technical environments,\nand we do have a few of those. But I agree it's not 100% clear, so\nalternatives are still definitely worth considering!\n\nThanks\nDavid\n\n>\n> > The other controls (AeFlickerMode and AeFlickerCustom) correspond to\n> > Android's anti-banding control. Again, we extend it to allow arbitrary\n> > flicker periods.\n> >\n> > Hope that all makes sense!\n> >\n> > Thanks\n> > David\n> >\n> > David Plowman (2):\n> > libcamera: controls: Add controls for AEC/AGC flicker avoidance\n> > ipa: raspberrypi: Handle AEC/AGC flicker controls\n> >\n> > src/ipa/raspberrypi/raspberrypi.cpp | 80 +++++++++++++++++++++++++++\n> > src/libcamera/control_ids.yaml | 84 +++++++++++++++++++++++------\n> > 2 files changed, 147 insertions(+), 17 deletions(-)\n>\n> --\n> Regards,\n>\n> Laurent Pinchart","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 9F002C326B\n\tfor ;\n\tTue, 4 Apr 2023 09:10:59 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 4A7526271C;\n\tTue, 4 Apr 2023 11:10:59 +0200 (CEST)","from mail-ot1-x332.google.com (mail-ot1-x332.google.com\n\t[IPv6:2607:f8b0:4864:20::332])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 23C836271C\n\tfor ;\n\tTue, 4 Apr 2023 11:10:58 +0200 (CEST)","by mail-ot1-x332.google.com with SMTP id\n\td22-20020a9d5e16000000b0069b5252ced7so16993577oti.13\n\tfor ;\n\tTue, 04 Apr 2023 02:10:58 -0700 (PDT)"],"DKIM-Signature":["v=1; 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charset=\"UTF-8\"","Subject":"Re: [libcamera-devel] [PATCH v3 0/2] Add flicker avoidance controls","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","From":"David Plowman via libcamera-devel ","Reply-To":"David Plowman ","Cc":"libcamera-devel@lists.libcamera.org","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "}},{"id":26845,"web_url":"https://patchwork.libcamera.org/comment/26845/","msgid":"<20230405015126.GB9915@pendragon.ideasonboard.com>","date":"2023-04-05T01:51:26","subject":"Re: [libcamera-devel] [PATCH v3 0/2] Add flicker avoidance controls","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/people/2/","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"content":"Hi David,\n\nOn Tue, Apr 04, 2023 at 10:10:45AM +0100, David Plowman wrote:\n> On Tue, 4 Apr 2023 at 06:46, Laurent Pinchartwrote:\n> > On Tue, Mar 28, 2023 at 09:55:19AM +0100, David Plowman via libcamera-devel wrote:\n> > > Hi everyone\n> > >\n> > > Here's an updated version of flicker avoidance controls. It's similar\n> > > to what I had previously, except that I've split the control which\n> > > gave an explicit flicker period into two, one for reporting a\n> > > currently detected value, and another for setting a custom flicker\n> > > period. So we now have 3 controls in total.\n> > >\n> > > In terms of Android, the AeFlickerDetected control corresponds fairly\n> > > directly to Android's scene_flicker control, which is (from my reading\n> > > of it) merely reporting any currently detected flicker period.\n> >\n> > That's my understanding too.\n> >\n> > > AeFlickerDetected, however, allows arbitrary flicker periods\n> > > to be identified, not just 50 or 60Hz.\n> >\n> > Out of curiosity, what are the use cases you envision for other\n> > frequencies ?\n> \n> I think the most obvious use cases are when people have LEDs that run\n> at other frequencies. Probably not such an issue for regular users,\n> but I could imagine it being useful in lab or technical environments,\n> and we do have a few of those. But I agree it's not 100% clear, so\n> alternatives are still definitely worth considering!\n\nI thought about LED lightning an hour after sending the question :-)\nThis sounds like a good use case. I don't have an alternative proposal,\nI think yours makes sense.\n\n> > > The other controls (AeFlickerMode and AeFlickerCustom) correspond to\n> > > Android's anti-banding control. Again, we extend it to allow arbitrary\n> > > flicker periods.\n> > >\n> > > Hope that all makes sense!\n> > >\n> > > Thanks\n> > > David\n> > >\n> > > David Plowman (2):\n> > > libcamera: controls: Add controls for AEC/AGC flicker avoidance\n> > > ipa: raspberrypi: Handle AEC/AGC flicker controls\n> > >\n> > > src/ipa/raspberrypi/raspberrypi.cpp | 80 +++++++++++++++++++++++++++\n> > > src/libcamera/control_ids.yaml | 84 +++++++++++++++++++++++------\n> > > 2 files changed, 147 insertions(+), 17 deletions(-)","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 92149C0F2A\n\tfor ;\n\tWed, 5 Apr 2023 01:51:22 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id BABE962756;\n\tWed, 5 Apr 2023 03:51:21 +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 0A5EF626E3\n\tfor ;\n\tWed, 5 Apr 2023 03:51:20 +0200 (CEST)","from pendragon.ideasonboard.com (fp76f193f3.tkyc206.ap.nuro.jp\n\t[118.241.147.243])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 6C453905;\n\tWed, 5 Apr 2023 03:51:18 +0200 (CEST)"],"DKIM-Signature":["v=1; a=rsa-sha256; c=relaxed/simple; d=libcamera.org;\n\ts=mail; t=1680659481;\n\tbh=cr5l7XzCQV5xoF4T2FHjG8cS2XTato81y22jvj5ycf8=;\n\th=Date:To:References:In-Reply-To:Subject:List-Id:List-Unsubscribe:\n\tList-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc:\n\tFrom;\n\tb=ESEBR6ke8nE9eHWCT/qTlT7P3o+Fr0hG4AMxDDA9cLfXwXFZa87lOoNEyOEL/D95t\n\tmY0JEeN+PdJsHudLgF4l5zcFYEibwL/Mx8YvbuaNDheoXipKPPo2ZrltO+rvFYao8L\n\thuCFR6aY4r5bwak+rtfrQrc3PwObtDRLFQh8dncTb5Rt6MVHjMlPZ/wt2vXIhJfaPe\n\tQZ+0q+Dato7eBeVLhPsYaeU8jGYL2Qo9gYlBkfrX85tBSPdaIbIYvT+Xe6FMF884fn\n\tTmLROMGuGrcALrpFjI971IooetTBA3QRMweCrisUHco+XJi47ipdn1v4It52WLcuei\n\tOK2sv1LzAe+EQ==","v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1680659479;\n\tbh=cr5l7XzCQV5xoF4T2FHjG8cS2XTato81y22jvj5ycf8=;\n\th=Date:From:To:Cc:Subject:References:In-Reply-To:From;\n\tb=ZCPC0IT5+EcX008NHJXzlZgpW7qvUa4C/UfhPOh8BKV8D0YvV1tdHspy5MlCh0q6n\n\tXsNnYm086Angj6VR/rGq+qaQwHxJjPLD03EgBGX5WO24fIH9s89tInwszcRG2TlGCT\n\tfeom453bKa1IcuIXIc72cK9QTci04A8ji9XykB9E="],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key; \n\tunprotected) header.d=ideasonboard.com\n\theader.i=@ideasonboard.com\n\theader.b=\"ZCPC0IT5\"; dkim-atps=neutral","Date":"Wed, 5 Apr 2023 04:51:26 +0300","To":"David Plowman ","Message-ID":"<20230405015126.GB9915@pendragon.ideasonboard.com>","References":"<20230328085521.7409-1-david.plowman@raspberrypi.com>\n\t<20230404054659.GP16648@pendragon.ideasonboard.com>\n\t","MIME-Version":"1.0","Content-Type":"text/plain; charset=utf-8","Content-Disposition":"inline","In-Reply-To":"","Subject":"Re: [libcamera-devel] [PATCH v3 0/2] Add flicker avoidance controls","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","From":"Laurent Pinchart via libcamera-devel\n\t","Reply-To":"Laurent Pinchart ","Cc":"libcamera-devel@lists.libcamera.org","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "}}]