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 9343149389 for ; Mon, 8 Apr 2024 21:55:12 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 2FD8468D39B; Tue, 9 Apr 2024 00:55:10 +0300 (EEST) Received: from haasn.dev (haasn.dev [78.46.187.166]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 9781868D342 for ; Tue, 9 Apr 2024 00:55:03 +0300 (EEST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=haasn.xyz; s=mail; t=1712613303; bh=s5zBVkF3x3hlXVsQcqmmxXYOB9Y1N4XBZbkrhLJq48c=; h=Date:From:To:Subject:In-Reply-To:References:From; b=YRNxY2LVza1Y7IlvqXfZYksit4N7OljXlxChB/gEAwcJRudPzSBm0blAByDKmE0pU byvEC29LPPWTb+tuK6yuIlXCWiDRsZxKKUAAOCwZuxAnjnr2ZwaDOgIU1XYYie++GN mrePVc5y5fTDaxFdiCXN/UZhkSJzb7ZAbspxv3RQ= Received: from localhost (ip-109-192-222-233.um38.pools.vodafone-ip.de [109.192.222.233]) by haasn.dev (Postfix) with ESMTPSA id 441DF410B5 for ; Mon, 8 Apr 2024 23:55:03 +0200 (CEST) Date: Mon, 8 Apr 2024 23:55:02 +0200 Message-ID: <20240408235502.GB24382@haasn.xyz> From: Niklas Haas To: FFmpeg development discussions and patches In-Reply-To: <20240408201833.GI6420@pb2> References: <20240405185721.111072-1-ffmpeg@haasn.xyz> <20240408201833.GI6420@pb2> MIME-Version: 1.0 Content-Disposition: inline Subject: Re: [FFmpeg-devel] [PATCH 01/11] avcodec: add avcodec_get_supported_config() 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 Mon, 08 Apr 2024 22:18:33 +0200 Michael Niedermayer wrote: > On Fri, Apr 05, 2024 at 08:57:11PM +0200, Niklas Haas wrote: > > From: Niklas Haas > > > > This replaces the myriad of existing lists in AVCodec by a unified API > > call, allowing us to (ultimately) trim down the sizeof(AVCodec) quite > > substantially, while also making this more trivially extensible. > > > > In addition to the already covered lists, add two new entries for color > > space and color range, mirroring the newly added negotiable fields in > > libavfilter. > > > > I decided to drop the explicit length field from the API proposed by > > Andreas Rheinhardt, because having it in place ended up complicating > > both the codec side and the client side implementations, while also > > being strictly less flexible (it's trivial to recover a length given > > a terminator, but requires allocation to add a terminator given > > a length). Using a terminator also presents less of a porting challenge > > for existing users of the current API. > > > > Once the deprecation period passes for the existing public fields, the > > rough plan is to move the commonly used fields (such as > > pix_fmt/sample_fmt) into FFCodec, possibly as a union of audio and video > > configuration types, and then implement the rarely used fields with > > custom callbacks. > > --- > > doc/APIchanges | 5 ++++ > > libavcodec/avcodec.c | 51 +++++++++++++++++++++++++++++++++++++ > > libavcodec/avcodec.h | 27 ++++++++++++++++++++ > > libavcodec/codec.h | 19 +++++++++++--- > > libavcodec/codec_internal.h | 21 +++++++++++++++ > > libavcodec/version.h | 4 +-- > > 6 files changed, 121 insertions(+), 6 deletions(-) > > This patchset seems to overlap a bit with AVOptionRanges > > I think ideally the user should at some point be able to query using some > API on a AVCodecContext/AVCodecParameters/AVFormatContex/AVStream > what for that specific instance are supported settings for each field > > The API here seems to use a enum, which can make sense but it differs from > how AVOption works which doesnt use enums to identify fields I didn't know AVOptionRanges exists; indeed it can be seen as somewhat overlapping here. That said, there is a vital distinction here: AVOptionRanges represents *static* limits on what options can be set (e.g. via `av_opt_set_int`), whereas this API represents *dynamic* limits on what can be coded. In particular, the list of supported colorspaces etc. can *depend* on the value of other options. Currently, only strict_std_compliance, but I can easily see this list growing in the future (e.g. for different profiles, dolbyvision, ...). That aside, I personally find an API based on strings and doubles rather cumbersome to use, especially when downstream clients expect an enum list. > > > [...] > -- > Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB > > Never trust a computer, one day, it may think you are the virus. -- Compn > _______________________________________________ > 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". _______________________________________________ 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".