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 D3DBA461CA for ; Tue, 9 May 2023 08:45:00 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id BEF5168C20B; Tue, 9 May 2023 11:44:57 +0300 (EEST) Received: from mail0.khirnov.net (red.khirnov.net [176.97.15.12]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 19B6668BC6A for ; Tue, 9 May 2023 11:44:51 +0300 (EEST) Received: from localhost (localhost [IPv6:::1]) by mail0.khirnov.net (Postfix) with ESMTP id D7E772404EC for ; Tue, 9 May 2023 10:44:50 +0200 (CEST) Received: from mail0.khirnov.net ([IPv6:::1]) by localhost (mail0.khirnov.net [IPv6:::1]) (amavisd-new, port 10024) with ESMTP id v2vdzOKhXGJX for ; Tue, 9 May 2023 10:44:50 +0200 (CEST) Received: from lain.khirnov.net (lain.khirnov.net [IPv6:2001:67c:1138:4306::3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "lain.khirnov.net", Issuer "smtp.khirnov.net SMTP CA" (verified OK)) by mail0.khirnov.net (Postfix) with ESMTPS id 54CFB240177 for ; Tue, 9 May 2023 10:44:50 +0200 (CEST) Received: by lain.khirnov.net (Postfix, from userid 1000) id 3B5021601B2; Tue, 9 May 2023 10:44:50 +0200 (CEST) From: Anton Khirnov To: FFmpeg development discussions and patches In-Reply-To: <20230508141542.GS1391451@pb2> References: <20230507133255.20881-1-anton@khirnov.net> <20230507133255.20881-4-anton@khirnov.net> <20230508141542.GS1391451@pb2> Mail-Followup-To: FFmpeg development discussions and patches Date: Tue, 09 May 2023 10:44:50 +0200 Message-ID: <168362189020.3843.14417317264187506189@lain.khirnov.net> User-Agent: alot/0.8.1 MIME-Version: 1.0 Subject: Re: [FFmpeg-devel] [PATCH 04/13] lavf: use AV_CODEC_PROP_FIELDS where appropriate 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: Quoting Michael Niedermayer (2023-05-08 16:15:42) > On Sun, May 07, 2023 at 03:32:46PM +0200, Anton Khirnov wrote: > > H.264 and mpeg12 parsers need to be adjusted at the same time to stop > > using the value of AVCodecContext.ticks_per_frame, because it is not set > > correctly unless the codec has been opened. Previously this would result > > in both the parser and lavf seeing the same incorrect value, which would > > cancel out. > > Updating lavf and not the parsers would result in correct value in lavf, > > but the wrong one in parsers, which would break some tests. > > --- > > libavcodec/h264_parser.c | 4 ++-- > > libavcodec/mpegvideo_parser.c | 2 +- > > libavformat/avformat.c | 9 ++++++--- > > libavformat/demux.c | 29 +++++++++++++++++++---------- > > libavformat/internal.h | 3 +++ > > 5 files changed, 31 insertions(+), 16 deletions(-) > > Doesnt this sort of change need a major ABI bump ? > it sounds like lavc and lavf interdepend here both ways No, we do not guarantee bug compatibility. Libavformat seeing ticks_per_frame=1 for codecs that set it to 2 upon being opened is a bug. Same for the parser. It just so happens that libavformat AND its internal parser instance see the same incorrect value and this cancels out in cases that are tested by FATE (it would break if we had more thorough tests for repeating single fields). I could split this into two patches, the first of which would fix one of the bugs, expose the other one, breaking some tests. Then the second patch would fix the second bug, fixing the tests again. It seems better to do it in a single step to avoid the noise. -- Anton Khirnov _______________________________________________ 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".