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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 34491C433FF for ; Sat, 27 Jul 2019 09:37:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 092E220651 for ; Sat, 27 Jul 2019 09:37:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728756AbfG0Jht (ORCPT ); Sat, 27 Jul 2019 05:37:49 -0400 Received: from relay7-d.mail.gandi.net ([217.70.183.200]:51605 "EHLO relay7-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727885AbfG0Jht (ORCPT ); Sat, 27 Jul 2019 05:37:49 -0400 X-Originating-IP: 176.158.46.5 Received: from aptenodytes (static-176-158-46-5.ftth.abo.bbox.fr [176.158.46.5]) (Authenticated sender: paul.kocialkowski@bootlin.com) by relay7-d.mail.gandi.net (Postfix) with ESMTPSA id B9F7A20004; Sat, 27 Jul 2019 09:37:45 +0000 (UTC) Date: Sat, 27 Jul 2019 11:37:45 +0200 From: Paul Kocialkowski To: Hans Verkuil Cc: linux-media@vger.kernel.org, Maxime Jourdan , Tomasz Figa , Stanimir Varbanov , Sylwester Nawrocki , Alexandre Courbot , Maxime Ripard , Nicolas Dufresne , Ezequiel Garcia , Boris Brezillon , Philipp Zabel Subject: Re: [PATCH 02/14] videodev2.h: add V4L2_FMT_FLAG_HAS_BITSTREAM_PARSER Message-ID: <20190727093745.GB16618@aptenodytes> References: <20190724110523.29248-1-hverkuil-cisco@xs4all.nl> <20190724110523.29248-3-hverkuil-cisco@xs4all.nl> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20190724110523.29248-3-hverkuil-cisco@xs4all.nl> User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Hi, On Wed 24 Jul 19, 13:05, Hans Verkuil wrote: > Add an enum_fmt format flag to specifically tag coded formats where > full bitstream parsing is supported by the device. > > Some stateful decoders are capable of fully parsing a bitstream, > but others require that userspace pre-parses the bitstream into > frames or fields (see the corresponding pixelformat descriptions > for details). > > If this flag is set, then this pre-parsing step is not required > (but still possible, of course). > > Signed-off-by: Hans Verkuil > --- > Documentation/media/uapi/v4l/vidioc-enum-fmt.rst | 8 ++++++++ > Documentation/media/videodev2.h.rst.exceptions | 1 + > include/uapi/linux/videodev2.h | 5 +++-- > 3 files changed, 12 insertions(+), 2 deletions(-) > > diff --git a/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst b/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst > index 822d6730e7d2..4e24e671f32e 100644 > --- a/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst > +++ b/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst > @@ -127,6 +127,14 @@ one until ``EINVAL`` is returned. > - This format is not native to the device but emulated through > software (usually libv4l2), where possible try to use a native > format instead for better performance. > + * - ``V4L2_FMT_FLAG_HAS_BITSTREAM_PARSER`` > + - 0x0004 > + - The hardware decoder for this compressed bitstream format (aka coded > + format) is capable of parsing the bitstream. Applications do not > + need to parse the bitstream themselves to find the boundaries between > + frames/fields. This flag can only be used in combination with the > + ``V4L2_FMT_FLAG_COMPRESSED`` flag, since this applies to compressed > + formats only. Should this flag be set for stateless codecs as well? It seems a bit over-kill for this case. I am not sure whether "compressed bitstream format" clearly only covers the formats used by stateful decoders and not the ones for stateless decoders. Cheers, Paul > > Return Value > diff --git a/Documentation/media/videodev2.h.rst.exceptions b/Documentation/media/videodev2.h.rst.exceptions > index 55cbe324b9fc..74fb9f00c12d 100644 > --- a/Documentation/media/videodev2.h.rst.exceptions > +++ b/Documentation/media/videodev2.h.rst.exceptions > @@ -180,6 +180,7 @@ replace define V4L2_PIX_FMT_FLAG_PREMUL_ALPHA reserved-formats > # V4L2 format flags > replace define V4L2_FMT_FLAG_COMPRESSED fmtdesc-flags > replace define V4L2_FMT_FLAG_EMULATED fmtdesc-flags > +replace define V4L2_FMT_FLAG_HAS_BITSTREAM_PARSER fmtdesc-flags > > # V4L2 tymecode types > replace define V4L2_TC_TYPE_24FPS timecode-type > diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h > index 2427bc4d8eba..8c5a28666b16 100644 > --- a/include/uapi/linux/videodev2.h > +++ b/include/uapi/linux/videodev2.h > @@ -774,8 +774,9 @@ struct v4l2_fmtdesc { > __u32 reserved[4]; > }; > > -#define V4L2_FMT_FLAG_COMPRESSED 0x0001 > -#define V4L2_FMT_FLAG_EMULATED 0x0002 > +#define V4L2_FMT_FLAG_COMPRESSED 0x0001 > +#define V4L2_FMT_FLAG_EMULATED 0x0002 > +#define V4L2_FMT_FLAG_HAS_BITSTREAM_PARSER 0x0004 > > /* Frame Size and frame rate enumeration */ > /* > -- > 2.20.1 > -- Paul Kocialkowski, Bootlin Embedded Linux and kernel engineering https://bootlin.com