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[79.124.17.100]) by mx.google.com with ESMTP id l23-20020a170906a41700b00a364b130599si1553009ejz.489.2024.01.31.11.47.56; Wed, 31 Jan 2024 11:47:56 -0800 (PST) Received-SPF: pass (google.com: domain of ffmpeg-devel-bounces@ffmpeg.org designates 79.124.17.100 as permitted sender) client-ip=79.124.17.100; Authentication-Results: mx.google.com; dkim=neutral (body hash did not verify) header.i=@niedermayer.cc header.s=gm1 header.b=AjQPiUSl; spf=pass (google.com: domain of ffmpeg-devel-bounces@ffmpeg.org designates 79.124.17.100 as permitted sender) smtp.mailfrom=ffmpeg-devel-bounces@ffmpeg.org Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 7ABD468D0B5; Wed, 31 Jan 2024 21:47:53 +0200 (EET) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from relay2-d.mail.gandi.net (relay2-d.mail.gandi.net [217.70.183.194]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 558E068CAFA for ; Wed, 31 Jan 2024 21:47:47 +0200 (EET) Received: by mail.gandi.net (Postfix) with ESMTPSA id A9E8A40005 for ; Wed, 31 Jan 2024 19:47:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=niedermayer.cc; s=gm1; t=1706730466; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc; bh=TaruN8yIsSkWaIpooc76IyOEJ1SflP/gVCFdAj9AIR4=; b=AjQPiUSl7BulnaxnXYqAhjHGtfMQ3wrYrKz+GpneRQ60mb1n6/aeqF4C9n47t+u4geMvAA lls5fUP6Lmis9FbNVDKlyksAOPBf48SVsHYmGimuoBAdgO4dqOM3JLuAwAZFoID5hoOfLi Xw9iqN4dyCGTVUhWe2Km0G6A06/MMRyKI6yS5xT3qiGkEPCyeDNabD/AkjbeCh1ou8rUR/ n3S1cXZ+hU0IL6w7jn58jbZCQWFSd0n1VUt1nelquorXI1IRWO45nwZJu/4JXqYDzEhPTs vK61RGIwrURg9M8hXjzDgDmAsyGh5pRLFb/VoT8k9jbm59D3L2hpbHDLgDfaDQ== From: Michael Niedermayer To: FFmpeg development discussions and patches Date: Wed, 31 Jan 2024 20:47:46 +0100 Message-Id: <20240131194746.11309-1-michael@niedermayer.cc> X-Mailer: git-send-email 2.17.1 X-GND-Sasl: michael@niedermayer.cc Subject: [FFmpeg-devel] [PATCH] avutil/rational: Document what is to be expected from av_d2q() of doubles representing rational numbers 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 MIME-Version: 1.0 Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" X-TUID: SgV9kJILn8YZ Signed-off-by: Michael Niedermayer --- libavutil/rational.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/libavutil/rational.h b/libavutil/rational.h index 8cbfc8e0669..c6ac9fb1d91 100644 --- a/libavutil/rational.h +++ b/libavutil/rational.h @@ -168,6 +168,10 @@ static av_always_inline AVRational av_inv_q(AVRational q) * In case of infinity, the returned value is expressed as `{1, 0}` or * `{-1, 0}` depending on the sign. * + * In general rational numbers with |num| <= 1<<26 && |den| <= 1<<26 + * can be recovered exactly from their double representation. + * (no exceptions where found within 100M random ones) + * * @param d `double` to convert * @param max Maximum allowed numerator and denominator * @return `d` in AVRational form