[{"id":30340,"web_url":"https://patchwork.libcamera.org/comment/30340/","msgid":"","date":"2024-07-05T06:44:49","subject":"Re: [PATCH v3 22/23] libtuning: lsc: Prevent negative values","submitter":{"id":17,"url":"https://patchwork.libcamera.org/api/people/17/","name":"Paul Elder","email":"paul.elder@ideasonboard.com"},"content":"On Wed, Jul 03, 2024 at 04:17:11PM +0200, Stefan Klug wrote:\n> In cases where the calibration image contains super dark areas, or when\n> an invalid blacklevel was supplied, the grid might get close to zero or\n> negative. This would have bad effects on the 1/grid later. So clamp the\n> values to a small positive number.\n> \n> Signed-off-by: Stefan Klug \n> Reviewed-by: Laurent Pinchart \n\nReviewed-by: Paul Elder \n\n> ---\n> utils/tuning/libtuning/modules/lsc/lsc.py | 5 ++++-\n> 1 file changed, 4 insertions(+), 1 deletion(-)\n> \n> diff --git a/utils/tuning/libtuning/modules/lsc/lsc.py b/utils/tuning/libtuning/modules/lsc/lsc.py\n> index 344a07a3d443..e0ca22ebe9bd 100644\n> --- a/utils/tuning/libtuning/modules/lsc/lsc.py\n> +++ b/utils/tuning/libtuning/modules/lsc/lsc.py\n> @@ -59,7 +59,10 @@ class LSC(Module):\n> def _lsc_single_channel(self, channel: np.array,\n> image: lt.Image, green_grid: np.array = None):\n> grid = self._get_grid(channel, image.w, image.h)\n> - grid -= image.blacklevel_16\n> + # Clamp the values to a small positive, so that the following 1/grid\n> + # doesn't produce negative results.\n> + grid = np.maximum(grid - image.blacklevel_16, 0.1)\n> +\n> if green_grid is None:\n> table = np.reshape(1 / grid, self.sector_shape[::-1])\n> else:\n> -- \n> 2.43.0\n>","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 4C27FBD87C\n\tfor ;\n\tFri, 5 Jul 2024 06:45:00 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 4432662E22;\n\tFri, 5 Jul 2024 08:44:59 +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 4E5D0619BE\n\tfor ;\n\tFri, 5 Jul 2024 08:44:57 +0200 (CEST)","from pyrite.rasen.tech (h175-177-049-156.catv02.itscom.jp\n\t[175.177.49.156])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 8C0FA8BF;\n\tFri, 5 Jul 2024 08:44:26 +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=\"FCaSFuLx\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1720161867;\n\tbh=ieU2dhGR4tEgHlrxYcVe38i9DsYN/7qneEBvrAUHoQQ=;\n\th=Date:From:To:Cc:Subject:References:In-Reply-To:From;\n\tb=FCaSFuLx3yE2gGMz4pqeDHQH4i1wv+4BueSfA2vV6FfwQcBcdRsKYVDJy1Pmvo5qX\n\tXh8e5oDbFVCO9oT2NTAkypLCdGeE0Tkage1GbrAJ4Wr/06NNa3HObcNdTtVl9BGqsZ\n\t+dwrBgWETEWGlKIE/axkK4QZmSBuLJUNlnIN4Nms=","Date":"Fri, 5 Jul 2024 15:44:49 +0900","From":"Paul Elder ","To":"Stefan Klug ","Cc":"libcamera-devel@lists.libcamera.org,\n\tLaurent Pinchart ","Subject":"Re: [PATCH v3 22/23] libtuning: lsc: Prevent negative values","Message-ID":"","References":"<20240703141726.252368-1-stefan.klug@ideasonboard.com>\n\t<20240703141726.252368-23-stefan.klug@ideasonboard.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=us-ascii","Content-Disposition":"inline","In-Reply-To":"<20240703141726.252368-23-stefan.klug@ideasonboard.com>","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\" "}}]