[{"id":20344,"web_url":"https://patchwork.libcamera.org/comment/20344/","msgid":"","date":"2021-10-21T02:15:33","subject":"Re: [libcamera-devel] [PATCH v2 07/13] ipa: ipu3: agc: Change\n\tanalogue gain limits","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/people/2/","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"content":"Hi Jean-Michel,\n\nThank you for the patch.\n\nOn Wed, Oct 20, 2021 at 05:46:01PM +0200, Jean-Michel Hautbois wrote:\n> The gains is currently set as a uint32_t while the analogue gain is\n\ns/gains/gain/\n\n> passed as a double. We also have a default maximum analogue gain of 15\n> which is quite high for a number of sensors.\n> \n> Use a maximum value of 8 which should really be configured by the IPA\n> and not fixed as it is now. While at it make it a double.\n> \n> Signed-off-by: Jean-Michel Hautbois \n> Reviewed-by: Kieran Bingham \n> Reviewed-by: Laurent Pinchart \n> ---\n> src/ipa/ipu3/algorithms/agc.cpp | 14 ++++++--------\n> 1 file changed, 6 insertions(+), 8 deletions(-)\n> \n> diff --git a/src/ipa/ipu3/algorithms/agc.cpp b/src/ipa/ipu3/algorithms/agc.cpp\n> index 8e1b6d8c..1bae1eb9 100644\n> --- a/src/ipa/ipu3/algorithms/agc.cpp\n> +++ b/src/ipa/ipu3/algorithms/agc.cpp\n> @@ -30,14 +30,10 @@ static constexpr uint32_t kInitialFrameMinAECount = 4;\n> /* Number of frames to wait between new gain/exposure estimations */\n> static constexpr uint32_t kFrameSkipCount = 6;\n> \n> -/* Maximum ISO value for analogue gain */\n> -static constexpr uint32_t kMinISO = 100;\n> -static constexpr uint32_t kMaxISO = 1500;\n> -\n> /* Maximum analogue gain value\n> * \\todo grab it from a camera helper */\n> -static constexpr uint32_t kMinGain = kMinISO / 100;\n> -static constexpr uint32_t kMaxGain = kMaxISO / 100;\n> +static constexpr double kMinGain = 1.0;\n> +static constexpr double kMaxGain = 8.0;\n> \n> /* Histogram constants */\n> static constexpr uint32_t knumHistogramBins = 256;\n> @@ -165,9 +161,11 @@ void Agc::lockExposureGain(uint32_t &exposure, double &gain)\n> \t\t\t\t\t\t\tminExposureLines_,\n> \t\t\t\t\t\t\tmaxExposureLines_);\n> \t\t\tnewExposure = currentExposure_ / exposure;\n> -\t\t\tgain = std::clamp(static_cast(gain * currentExposure_ / newExposure), kMinGain, kMaxGain);\n> +\t\t\tgain = std::clamp(gain * currentExposure_ / newExposure,\n> +\t\t\t\t\t kMinGain, kMaxGain);\n> \t\t} else if (currentShutter >= maxShutterSpeed) {\n> -\t\t\tgain = std::clamp(static_cast(gain * currentExposure_ / currentExposureNoDg_), kMinGain, kMaxGain);\n> +\t\t\tgain = std::clamp(gain * currentExposure_ / currentExposureNoDg_,\n> +\t\t\t\t\t kMinGain, kMaxGain);\n> \t\t\tnewExposure = currentExposure_ / gain;\n> \t\t\texposure = std::clamp(exposure * currentExposure_ / newExposure,\n> \t\t\t\t\t\t\tminExposureLines_,","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 3E78FBF415\n\tfor ;\n\tThu, 21 Oct 2021 02:15:55 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id B08D668F5B;\n\tThu, 21 Oct 2021 04:15:54 +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 B29A360124\n\tfor ;\n\tThu, 21 Oct 2021 04:15:52 +0200 (CEST)","from pendragon.ideasonboard.com (62-78-145-57.bb.dnainternet.fi\n\t[62.78.145.57])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 2B12393;\n\tThu, 21 Oct 2021 04:15:52 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com;\n\tdkim=fail reason=\"signature verification failed\" (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"MwyY0fL6\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1634782552;\n\tbh=TvhXr8868ekhI3HBddLqgI56SCHSqAFk2m2LkBOnWFQ=;\n\th=Date:From:To:Cc:Subject:References:In-Reply-To:From;\n\tb=MwyY0fL6sNarnoItNnxwCadK9OkJkYwWAWXbceuoQzqoU/qgTJFs+4MSobKlomh0P\n\tqxPxxtapihL0ZZVKgkgJmxaSNgjCMTdT0cpFxyNroTdVi+rEAtI9Zf3mqzzDeVzt3M\n\t+aknPoGDqGUcQnKzEtijpfno6nG1xzNZOuL6A6Sc=","Date":"Thu, 21 Oct 2021 05:15:33 +0300","From":"Laurent Pinchart ","To":"Jean-Michel Hautbois ","Message-ID":"","References":"<20211020154607.180161-1-jeanmichel.hautbois@ideasonboard.com>\n\t<20211020154607.180161-8-jeanmichel.hautbois@ideasonboard.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=utf-8","Content-Disposition":"inline","In-Reply-To":"<20211020154607.180161-8-jeanmichel.hautbois@ideasonboard.com>","Subject":"Re: [libcamera-devel] [PATCH v2 07/13] ipa: ipu3: agc: Change\n\tanalogue gain limits","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","Cc":"libcamera-devel@lists.libcamera.org","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "}}]