From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 72443C388F9 for ; Sun, 1 Nov 2020 00:39:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1D83722226 for ; Sun, 1 Nov 2020 00:39:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="HoNjkkI0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726159AbgKAAjD (ORCPT ); Sat, 31 Oct 2020 20:39:03 -0400 Received: from perceval.ideasonboard.com ([213.167.242.64]:58304 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726138AbgKAAjD (ORCPT ); Sat, 31 Oct 2020 20:39:03 -0400 Received: from pendragon.ideasonboard.com (62-78-145-57.bb.dnainternet.fi [62.78.145.57]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id B5C9A240; Sun, 1 Nov 2020 01:39:00 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1604191140; bh=JasllCkg6ZfCScPS0C1BvgdiP90pDqzyShttsshoU6Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=HoNjkkI0tAuoloSnaxciPdkBH/WSQEmmkng7E0XLAKas5WbuiqUNllTRjlzuA+fwS TAJm12Xfh/n/fuukOts1Jtn0nkNLe3DCO1ZyC156sE4wZpcsCFs13Xl2pBUyq5zt4B rIwCJmtKxoT+7maYxUtHNaDw+J7ulho83Oar3n1E= Date: Sun, 1 Nov 2020 02:38:11 +0200 From: Laurent Pinchart To: Nicolas Dufresne Cc: linux-media@vger.kernel.org, Sakari Ailus , Hans Verkuil , Dylan Yip , Vishal Sagar Subject: Re: [PATCH/RFC 15/16] media: v4l2: Add 10-, 12- and 16-bpc 4:4:4 packed VUY formats Message-ID: <20201101003811.GD4225@pendragon.ideasonboard.com> References: <20200923024333.920-1-laurent.pinchart@ideasonboard.com> <20200923024333.920-16-laurent.pinchart@ideasonboard.com> <9254388432492f46a38af8cfe5fb927f63e9e73b.camel@ndufresne.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <9254388432492f46a38af8cfe5fb927f63e9e73b.camel@ndufresne.ca> Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Hi Nicolas, On Thu, Sep 24, 2020 at 02:24:44PM -0400, Nicolas Dufresne wrote: > Le mercredi 23 septembre 2020 à 05:43 +0300, Laurent Pinchart a écrit : > > Add three new formats storing packed YUV 4:4:4 in 10-, 12- and 16-bpc > > variants, with component order VUY. They are used by the Xilinx Video > > Frame Buffer Read/Write IP cores. > > > > Signed-off-by: Laurent Pinchart > > --- > > .../media/v4l/pixfmt-packed-yuv.rst | 55 +++++++++++++++++++ > > include/uapi/linux/videodev2.h | 3 + > > 2 files changed, 58 insertions(+) > > > > diff --git a/Documentation/userspace-api/media/v4l/pixfmt-packed-yuv.rst b/Documentation/userspace-api/media/v4l/pixfmt-packed-yuv.rst > > index 3c7c8e38b7b7..4753ee8c6b7d 100644 > > --- a/Documentation/userspace-api/media/v4l/pixfmt-packed-yuv.rst > > +++ b/Documentation/userspace-api/media/v4l/pixfmt-packed-yuv.rst > > @@ -264,6 +264,61 @@ the second byte and Y'\ :sub:`7-0` in the third byte. > > applications and drivers. > > > > > > +The next table lists the packed YUV 4:4:4 formats with more than 8 bits per > > +component. They are named similarly to the formats with less than 8 bits per > > +components, based on the order of the Y, Cb and Cr components as seen in a > > +word, which is then stored in memory in little endian byte order, and on the > > +number of bits for each component. > > + > > +.. flat-table:: Packed YUV Image Formats (more than 8bpc) > > + :header-rows: 1 > > + :stub-columns: 0 > > + > > + * - Identifier > > + - Code > > + - Byte 0 > > + - Byte 1 > > + - Byte 2 > > + - Byte 3 > > + - Byte 4 > > + - Byte 5 > > + > > + * .. _V4L2-PIX-FMT-XVUY2101010: > > + > > + - ``V4L2_PIX_FMT_XVUY2101010`` > > + - 'VY30' > > + > > + - Y'\ :sub:`7-0` > > + - Cb\ :sub:`5-0` Y'\ :sub:`9-8` > > + - Cr\ :sub:`3-0` Cb\ :sub:`9-6` > > + - `-`\ :sub:`1-0` Cr\ :sub:`9-4` > > + - > > + > > + * .. _V4L2-PIX-FMT-XVUY4121212: > > + > > + - ``V4L2_PIX_FMT_XVUY4121212`` > > + - 'VY36' > > + > > + - Y'\ :sub:`7-0` > > + - Cb\ :sub:`3-0` Y'\ :sub:`11-8` > > + - Cb\ :sub:`11-4` > > + - Cr\ :sub:`7-0` > > + - `-`\ :sub:`3-0` Cr\ :sub:`11-8` > > + - > > + > > + * .. _V4L2-PIX-FMT-VUY161616: > > + > > + - ``V4L2_PIX_FMT_VUY161616`` > > + - 'VY40' > > + > > + - Y'\ :sub:`7-0` > > + - Y'\ :sub:`15-8` > > + - Cb\ :sub:`7-0` > > + - Cb\ :sub:`15-8` > > + - Cr\ :sub:`7-0` > > + - Cr\ :sub:`15-8` > > + > > + > > 4:2:2 Subsampling > > ================= > > > > diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h > > index 503a938ea98c..9b4cab651df7 100644 > > --- a/include/uapi/linux/videodev2.h > > +++ b/include/uapi/linux/videodev2.h > > @@ -605,6 +605,9 @@ struct v4l2_pix_format { > > #define V4L2_PIX_FMT_YUVA32 v4l2_fourcc('Y', 'U', 'V', 'A') /* 32 YUVA-8-8-8-8 */ > > #define V4L2_PIX_FMT_YUVX32 v4l2_fourcc('Y', 'U', 'V', 'X') /* 32 YUVX-8-8-8-8 */ > > #define V4L2_PIX_FMT_M420 v4l2_fourcc('M', '4', '2', '0') /* 12 YUV 4:2:0 2 lines y, 1 line uv interleaved */ > > +#define V4L2_PIX_FMT_XVUY2101010 v4l2_fourcc('V', 'Y', '3', '0') /* 32 XVUY-2-10-10-10 */ > > +#define V4L2_PIX_FMT_XVUY4121212 v4l2_fourcc('V', 'Y', '3', '6') /* 40 XVUY-4-12-12-12 */ > > +#define V4L2_PIX_FMT_VUY161616 v4l2_fourcc('V', 'Y', '4', '8') /* 48 VUY-16-16-16 */ > > That is very hard to read. I'm fine with being more verbose, but I > think it would be nice if it remains human readable. A possible fix > could be: > > V4L2_PIX_FMT_XVUY_2_10_10_10 Hans has proposed an interleave naming scheme in the review of 13/16. This would become X2V10U10Y10. He also mentioned an alternative option that would match your proposal above. I don't have a strong preference. Can you and Hans agree on the best option ? > Another approach is a bit-per-component and pixel size approach. That > one would be XYUV10_32. It is more cryptic, and you need more doc to > understand. > > That brings me to endianness, I believe it does matter for these > unaligned component, so that should be documented (little). That's already documented in Documentation/userspace-api/media/v4l/pixfmt-packed-yuv.rst. > > /* two planes -- one Y, one Cr + Cb interleaved */ > > #define V4L2_PIX_FMT_NV12 v4l2_fourcc('N', 'V', '1', '2') /* 12 Y/CbCr 4:2:0 */ -- Regards, Laurent Pinchart