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 13FDD43CA0 for ; Thu, 4 Aug 2022 13:49:35 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 29F5468B7E1; Thu, 4 Aug 2022 16:49:33 +0300 (EEST) Received: from relay3-d.mail.gandi.net (relay3-d.mail.gandi.net [217.70.183.195]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id EBC0668B743 for ; Thu, 4 Aug 2022 16:49:26 +0300 (EEST) Received: (Authenticated sender: michael@niedermayer.cc) by mail.gandi.net (Postfix) with ESMTPSA id 0A72760008 for ; Thu, 4 Aug 2022 13:49:25 +0000 (UTC) Date: Thu, 4 Aug 2022 15:49:24 +0200 From: Michael Niedermayer To: FFmpeg development discussions and patches Message-ID: <20220804134924.GJ2088045@pb2> References: <20220802165421.137563-1-george@nsup.org> MIME-Version: 1.0 In-Reply-To: <20220802165421.137563-1-george@nsup.org> Subject: Re: [FFmpeg-devel] [PATCH 1/7] lavu/pixfmt: summarize yuv naming conventions 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: multipart/mixed; boundary="===============8446079655535138843==" Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: --===============8446079655535138843== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="vFj1JTFBn4Zx1dEI" Content-Disposition: inline --vFj1JTFBn4Zx1dEI Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Aug 02, 2022 at 06:54:15PM +0200, Nicolas George wrote: > Signed-off-by: Nicolas George > --- > libavutil/pixfmt.h | 17 +++++++++++++++++ > 1 file changed, 17 insertions(+) >=20 >=20 > Identical to the one I posted last week. >=20 >=20 > diff --git a/libavutil/pixfmt.h b/libavutil/pixfmt.h > index 2d3927cc3f..3d0f92ed4d 100644 > --- a/libavutil/pixfmt.h > +++ b/libavutil/pixfmt.h > @@ -60,6 +60,23 @@ > * For all the 8 bits per pixel formats, an RGB32 palette is in data[1] = like > * for pal8. This palette is filled in automatically by the function > * allocating the picture. > + * > + * @par > + * Summary of the naming conventions for YUV formats: > + * 444 422 440 420 411 410 > + * =E2=95=8B=E2=94=81=E2=95=8B=E2=94=81=E2=95=8B=E2=94=81=E2=95=8B=E2=94= =81=E2=95=8B =E2=95=8B=E2=94=81=E2=94=BF=E2=94=81=E2=95=8B=E2=94=81=E2=94= =BF=E2=94=81=E2=95=8B =E2=95=8B=E2=94=81=E2=95=8B=E2=94=81=E2=95=8B=E2=94= =81=E2=95=8B=E2=94=81=E2=95=8B =E2=95=8B=E2=94=81=E2=94=BF=E2=94=81=E2=95= =8B=E2=94=81=E2=94=BF=E2=94=81=E2=95=8B =E2=95=8B=E2=94=81=E2=94=BF=E2=94= =81=E2=94=BF=E2=94=81=E2=94=BF=E2=94=81=E2=95=8B =E2=95=8B=E2=94=81=E2=94= =BF=E2=94=81=E2=94=BF=E2=94=81=E2=94=BF=E2=94=81=E2=95=8B > + * =E2=95=8B=E2=94=81=E2=95=8B=E2=94=81=E2=95=8B=E2=94=81=E2=95=8B=E2=94= =81=E2=95=8B =E2=95=8B=E2=94=81=E2=94=BF=E2=94=81=E2=95=8B=E2=94=81=E2=94= =BF=E2=94=81=E2=95=8B =E2=95=82=E2=94=80=E2=95=82=E2=94=80=E2=95=82=E2=94= =80=E2=95=82=E2=94=80=E2=95=82 =E2=95=82=E2=94=80=E2=94=BC=E2=94=80=E2=95= =82=E2=94=80=E2=94=BC=E2=94=80=E2=95=82 =E2=95=8B=E2=94=81=E2=94=BF=E2=94= =81=E2=94=BF=E2=94=81=E2=94=BF=E2=94=81=E2=95=8B =E2=95=82=E2=94=80=E2=94= =BC=E2=94=80=E2=94=BC=E2=94=80=E2=94=BC=E2=94=80=E2=95=82 > + * =E2=95=8B=E2=94=81=E2=95=8B=E2=94=81=E2=95=8B=E2=94=81=E2=95=8B=E2=94= =81=E2=95=8B =E2=95=8B=E2=94=81=E2=94=BF=E2=94=81=E2=95=8B=E2=94=81=E2=94= =BF=E2=94=81=E2=95=8B =E2=95=8B=E2=94=81=E2=95=8B=E2=94=81=E2=95=8B=E2=94= =81=E2=95=8B=E2=94=81=E2=95=8B =E2=95=8B=E2=94=81=E2=94=BF=E2=94=81=E2=95= =8B=E2=94=81=E2=94=BF=E2=94=81=E2=95=8B =E2=95=8B=E2=94=81=E2=94=BF=E2=94= =81=E2=94=BF=E2=94=81=E2=94=BF=E2=94=81=E2=95=8B =E2=95=82=E2=94=80=E2=94= =BC=E2=94=80=E2=94=BC=E2=94=80=E2=94=BC=E2=94=80=E2=95=82 > + * =E2=95=8B=E2=94=81=E2=95=8B=E2=94=81=E2=95=8B=E2=94=81=E2=95=8B=E2=94= =81=E2=95=8B =E2=95=8B=E2=94=81=E2=94=BF=E2=94=81=E2=95=8B=E2=94=81=E2=94= =BF=E2=94=81=E2=95=8B =E2=95=82=E2=94=80=E2=95=82=E2=94=80=E2=95=82=E2=94= =80=E2=95=82=E2=94=80=E2=95=82 =E2=95=82=E2=94=80=E2=94=BC=E2=94=80=E2=95= =82=E2=94=80=E2=94=BC=E2=94=80=E2=95=82 =E2=95=8B=E2=94=81=E2=94=BF=E2=94= =81=E2=94=BF=E2=94=81=E2=94=BF=E2=94=81=E2=95=8B =E2=95=82=E2=94=80=E2=94= =BC=E2=94=80=E2=94=BC=E2=94=80=E2=94=BC=E2=94=80=E2=95=82 > + * =E2=95=8B=E2=94=81=E2=95=8B=E2=94=81=E2=95=8B=E2=94=81=E2=95=8B=E2=94= =81=E2=95=8B =E2=95=8B=E2=94=81=E2=94=BF=E2=94=81=E2=95=8B=E2=94=81=E2=94= =BF=E2=94=81=E2=95=8B =E2=95=8B=E2=94=81=E2=95=8B=E2=94=81=E2=95=8B=E2=94= =81=E2=95=8B=E2=94=81=E2=95=8B =E2=95=8B=E2=94=81=E2=94=BF=E2=94=81=E2=95= =8B=E2=94=81=E2=94=BF=E2=94=81=E2=95=8B =E2=95=8B=E2=94=81=E2=94=BF=E2=94= =81=E2=94=BF=E2=94=81=E2=94=BF=E2=94=81=E2=95=8B =E2=95=8B=E2=94=81=E2=94= =BF=E2=94=81=E2=94=BF=E2=94=81=E2=94=BF=E2=94=81=E2=95=8B > + * where > + * =E2=94=BC=E2=94=80=E2=94=BC =3D luma pixel =E2=95=8B=E2=94=81=E2=95= =8B =3D chroma pixel > + * =E2=94=BC=E2=94=80=E2=94=BC =E2=95=8B=E2=94=81=E2=95=8B > + * > + * yuv4ab =E2=86=92 > + * log2_chroma_w =3D log=E2=82=82(4/a) > + * log2_chroma_h =3D b =3D=3D a ? 0 : b =3D=3D 0 ? log2_chroma_w : unus= ed > + * i.e. a =3D horizontally, number of luma pixels for four chroma pixels > */ You seem to describe samples as rectangular areas of constant value IIUC. If you look at the ITU/ISO specs (mpeg2, h264 or others) they are described by point samples. The desity of samples matches. While the default locations do not. What you list above are where probably most sane people would place the samples. But ISO/ITU, probably because of historic TV standard reasons and interlacing convertion reasons place the chroma samples in a more crooked w= ay I think either the ascii art should be adapted or the text should clarify this difference thx [...] --=20 Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB "Nothing to hide" only works if the folks in power share the values of you and everyone you know entirely and always will -- Tom Scott --vFj1JTFBn4Zx1dEI Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iF0EABEIAB0WIQSf8hKLFH72cwut8TNhHseHBAsPqwUCYuvOYQAKCRBhHseHBAsP qwMpAJ0cKKk3R5QzpHMCThh6EnZ4ecSj5ACfVkaXTP9SFDN0AJbeWnh33FBg/iM= =X2Rh -----END PGP SIGNATURE----- --vFj1JTFBn4Zx1dEI-- --===============8446079655535138843== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ 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". --===============8446079655535138843==--