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 BB3F84A93C for ; Wed, 24 Apr 2024 11:19:09 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 706E568D2A1; Wed, 24 Apr 2024 14:19:07 +0300 (EEST) Received: from mout-p-202.mailbox.org (mout-p-202.mailbox.org [80.241.56.172]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 4A46568CFCE for ; Wed, 24 Apr 2024 14:19:00 +0300 (EEST) Received: from smtp1.mailbox.org (smtp1.mailbox.org [10.196.197.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mout-p-202.mailbox.org (Postfix) with ESMTPS id 4VPc1r5jhmz9sWG for ; Wed, 24 Apr 2024 13:18:56 +0200 (CEST) Message-ID: Date: Wed, 24 Apr 2024 16:48:54 +0530 MIME-Version: 1.0 Content-Language: en-US To: ffmpeg-devel@ffmpeg.org References: <20240424110257.38715-1-ffmpeg@haasn.xyz> From: Gyan Doshi In-Reply-To: <20240424110257.38715-1-ffmpeg@haasn.xyz> Subject: Re: [FFmpeg-devel] [PATCH 0/5] replace scale2ref by scale=rw:rh 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-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: On 2024-04-24 04:21 pm, Niklas Haas wrote: > As discussed in my previous series for fixing scale2ref[1], this filter > is fundamentally broken, and the only real fix would be to switch to > activate(), or ideally FFFrameSync. > > [1] https://ffmpeg.org//pipermail/ffmpeg-devel/2024-March/323382.html > > The main thing making this difficult is the fact that scale2ref also > wants to output ref frames to its secondary output, which FFFrameSync > does not support, and which is ultimately at least part of the root > cause of trac #10795. > > Since this is in principle completely unnecessary (users can just > 'split' the ref input and have it be consumed by vf_scale), and to make > the design of this filter a bit more robust and maintainable, switch to > an approach where vf_scale itself gains the ability to reference > a secondary input stream, using the "ref_*" series of variables. > > This makes the current [i][ri]scale2ref[o][ro] equivalent to the only > slightly more verbose [ri]split[t][ro]; [i][t]scale=rw:rh[o]. (And > conversely, it is no longer necessary to use nullsink to consume an > unused [ro]) In principle, a good idea, but how does this impact memory use and speed in the not-so-uncommon scenario where multiple overlay targets are scaled 2 ref and then overlaid e.g. in current flow: [a][base]scale2ref[a][ref]; [b][ref]scale2ref[b][ref[; [c][ref]scale2ref[c][ref[; [d][ref]scale2ref[d][ref[; [ref][a]overlay[ref]; [ref][b]overlay[ref]; [ref][c]overlay[ref]; [ref][d]overlay[ref]; in new flow: [base]split=5[base][refa][refb][refc][refd]; [a][refa]scale[a]; [b][refb]scale[b]; [c][refc]scale[c]; [d][refd]scale[d]; [base][a]overlay[outa]; [outa][b]overlay[outb]; [outb][c]overlay[outc]; [outc][d]overlay[out]; Regards, Gyan _______________________________________________ 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".