From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by master.gitmailbox.com (Postfix) with ESMTP id C1C2D471C4 for ; Sat, 28 Oct 2023 11:18:27 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id D4FD468CA21; Sat, 28 Oct 2023 14:18:24 +0300 (EEST) Received: from haasn.dev (haasn.dev [78.46.187.166]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 24ACB68C7AD for ; Sat, 28 Oct 2023 14:18:18 +0300 (EEST) Received: from haasn.dev (unknown [10.30.0.2]) by haasn.dev (Postfix) with ESMTP id CFE0940C3B for ; Sat, 28 Oct 2023 13:18:17 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=haasn.xyz; s=mail; t=1698491897; bh=nY73LWWQecgxi5KL/VuAYbFEQ0yh0KeGVBr3Hr7tIsw=; h=Date:From:To:Subject:In-Reply-To:References:From; b=V9KfXse8r4dic7HdEP8/zfSDlZNxsF9ZVVwswKzF0sQQiKNHoBr/HKAdgnDFJESn/ xq0JVwUOs8H9bAaHcnMESwBx0Q8VyaKlkyCDM9kBJF6NTo1tV2GnUmjZtyMaFGhvmk uUL+8jE6iOH6ORh4vgrgVcq7i3uXhLJrVqWZO2T4= Date: Sat, 28 Oct 2023 13:18:17 +0200 Message-ID: <20231028131817.GB20693@haasn.xyz> From: Niklas Haas To: FFmpeg development discussions and patches In-Reply-To: <20231028125014.GB12204@haasn.xyz> References: <20231027170446.63684-1-ffmpeg@haasn.xyz> <20231027170446.63684-4-ffmpeg@haasn.xyz> <20231027210125.GZ3543730@pb2> <20231028125014.GB12204@haasn.xyz> MIME-Version: 1.0 Content-Disposition: inline Subject: Re: [FFmpeg-devel] [PATCH 4/8] avfilter/vf_scale: properly respect to input colorimetry X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: On Sat, 28 Oct 2023 12:50:14 +0200 Niklas Haas wrote: > On Fri, 27 Oct 2023 23:01:25 +0200 Michael Niedermayer wrote: > > On Fri, Oct 27, 2023 at 07:04:42PM +0200, Niklas Haas wrote: > > > From: Niklas Haas > > > > > > This code, as written, skips sws_init_context if scale->in_range was not > > > set, even if scale->in_frame_range is set to something. So this would > > > hit the 'no sws context' fast path in scale_frame and skip color range > > > conversion even where technically required. This had the effect of, in > > > practice, effectively applying limited/full range conversion if and only > > > if you set e.g. a nonzero yuv color matrix, which is obviously > > > undesirable behavior. > > > > > > Second, the assignment of out->color_range inside the branch would fail > > > to properly propagate tags for any actually applied conversion, for > > > example on conversion to a forced full range format. > > > > > > Solve both of these problems and make the code much easier to understand > > > and follow by doing the following: > > > > > > 1. Always initialize sws context on get_props > > > 2. Always use sws_getColorspaceDetails + sws_setColorspaceDetails to > > > fix the conversion matrices per-frame. > > > 3. Rather than testing if the context exists, do the no-op test after > > > settling the above values and deciding what conversion to actually > > > perform. > > > --- > > > libavfilter/vf_scale.c | 186 +++++++++++++++++------------------------ > > > 1 file changed, 76 insertions(+), 110 deletions(-) > > > > This breaks > > tickets/2939/lena.jpg > > > > (color looks slightly wrong compared to reference lena image) > > How do I reproduce this? I tested with: > > ffmpeg -i lena.jpg lena.png > > But the resulting checksum was identical before and after this commit. Nvm, I see the issue. Actually, the bug is in patch 1 - the logic is insufficient to cover all cases, since ff_sws_init_range_convert is never re-called after changing range. I will rewrite that commit, which should fix this one also. _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".