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 F202E4B332 for ; Thu, 4 Jul 2024 17:59:18 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id F0D9368D820; Thu, 4 Jul 2024 20:59:16 +0300 (EEST) Received: from haasn.dev (haasn.dev [78.46.187.166]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id D71F568D683 for ; Thu, 4 Jul 2024 20:59:10 +0300 (EEST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=haasn.xyz; s=mail; t=1720115950; bh=EHwT3ZboUSl3mo6vyFIAdW0dTnnSEglHq9+JNxiUrFU=; h=Date:From:To:Subject:In-Reply-To:References:From; b=ug0e/Xggg8OWCqoGOwMbAPpxhYMcIC/EqbPBMgKB7QizwC3oDeKGuau3YOCwLBpZ6 /co98ZwwYErxmYeNdxFTRa7h8eiFP1x6r+YJ7TyD2mm5gy4F+xaELTy5RunqhlWSq7 6m5RThIiQvdqO6HhoSy2WlurxjTjMMTrEcTKSvYw= Received: from haasn.dev (unknown [10.30.0.2]) by haasn.dev (Postfix) with ESMTP id A6C5940064 for ; Thu, 4 Jul 2024 19:59:10 +0200 (CEST) Date: Thu, 4 Jul 2024 19:59:10 +0200 Message-ID: <20240704195910.GG4933@haasn.xyz> From: Niklas Haas To: FFmpeg development discussions and patches In-Reply-To: <20240704195656.GC4933@haasn.xyz> References: <20240704143104.1821386-1-ffmpeg@haasn.xyz> <20240704195656.GC4933@haasn.xyz> MIME-Version: 1.0 Content-Disposition: inline Subject: Re: [FFmpeg-devel] [PATCH v2 1/8] swscale: document SWS_FULL_CHR_H_* flags 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 Thu, 04 Jul 2024 19:56:56 +0200 Niklas Haas wrote: > On Thu, 04 Jul 2024 16:24:24 +0100 Andrew Sayers wrote: > > On Thu, Jul 04, 2024 at 04:30:57PM +0200, Niklas Haas wrote: > > > From: Niklas Haas > > > > > > Based on my best understanding of what they do, given the source code. > > > --- > > > libswscale/swscale.h | 28 ++++++++++++++++++++++++++-- > > > 1 file changed, 26 insertions(+), 2 deletions(-) > > > > > > diff --git a/libswscale/swscale.h b/libswscale/swscale.h > > > index 9d4612aaf3..e22931cab4 100644 > > > --- a/libswscale/swscale.h > > > +++ b/libswscale/swscale.h > > > @@ -82,11 +82,35 @@ const char *swscale_license(void); > > > #define SWS_PRINT_INFO 0x1000 > > > > > > //the following 3 flags are not completely implemented > > > -//internal chrominance subsampling info > > > + > > > +/** > > > + * Perform full chroma upsampling when converting to RGB as part of scaling. > > > > Nitpick: "as part of scaling" seems redundant - can it be removed? > > I wrote it this way because, afaict, this flag does not affect unscaled > special converters (yuv->rgba). But I can remove it if you still think > it's unnecessary. How about: "Perform full chroma upsampling when upscaling to RGB"? > > > > > > + * > > > + * For example, when converting 50x50 yuv420p to 100x100 rgba, setting this flag > > > + * will scale the chroma plane from 25x25 to 100x100 (4:4:4), and then convert > > > + * the 100x100 yuv444p image to rgba in the final output step. > > > + * > > > + * Without this flag, the chroma plane is instead scaled to 50x100 (4:2:2), > > > + * with a single chroma sample being re-used for both horizontally adjacent RGBA > > > + * output pixels. > > > > Nitpick: this would be more readable as "for both of the...". > > > > Consider the following sentence: > > > > Without this flag, the chroma plane is instead scaled to 50x100 (4:2:2), > > with a single chroma sample being re-used for both horizontally and vertically > > adjacent RGBA output pixels. > > > > Using "both of the" would make it clear what "both" refers to before the reader > > starts doing branch-prediction in their head. > > Fixed. > > > > > Otherwise, LGTM (by which I mean it's clear, not that I know whether it's > > correct). > > _______________________________________________ > > 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".