From patchwork Tue Apr 26 12:57:27 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Dufresne X-Patchwork-Id: 12827056 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 40615C433F5 for ; Tue, 26 Apr 2022 12:58:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350329AbiDZNBP (ORCPT ); Tue, 26 Apr 2022 09:01:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45192 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349620AbiDZNBJ (ORCPT ); Tue, 26 Apr 2022 09:01:09 -0400 Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BDEAE177D42; Tue, 26 Apr 2022 05:58:01 -0700 (PDT) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: nicolas) with ESMTPSA id E17851F4398D DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1650977880; bh=9s/jwY2vdLbXyetN/42aw11t+0XH2cY1iw+Tw9pwgjM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SD2dBeBEPnw4SkKggKXX/LgBYHxa0D6QIbxvHQ8/1wQl/7UOkD6cR0nng3rxHTK4G n7TTUOrZIfzBJtD567KrT5hA1/ysn1AD9ftnij4IGMB74FEfkJY628zjIOAiPXvc2r SP4xE6HTr9ibOgOhPGCaXkm79eH2w5A7+VjhJOwzZB8TcsGE5juocOfezPv1eOHO4o fR2Cs1deoXfdrCXcPkP86lfYe1L0gy82ntgKY65xgtPKF/ZgNRkQmxg5rlU13xEBOx KeUDK5Qba1zszzOL2QfBobU9Ah45QbrHelGSBaTW4W672qEaMl2ELZOvSxr8oKFXNC Xl/rppY7ZHQDA== From: Nicolas Dufresne To: Mauro Carvalho Chehab Cc: nicolas@ndufresne.ca, linux-media@vger.kernel.org, Sebastian Fricke , linux-kernel@vger.kernel.org Subject: [PATCH v4 01/24] media: doc: Document dual use of H.264 pic_num/frame_num Date: Tue, 26 Apr 2022 08:57:27 -0400 Message-Id: <20220426125751.108293-2-nicolas.dufresne@collabora.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220426125751.108293-1-nicolas.dufresne@collabora.com> References: <20220426125751.108293-1-nicolas.dufresne@collabora.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org These two fields need documentation as they have dual meaning. It is also confusing since pic_num is a derived value from frame_num, so this should help application developers. If we ever need to make a V2 of this API, I would suggest to remove pic_num entirely. Signed-off-by: Nicolas Dufresne Reviewed-by: Sebastian Fricke --- .../media/v4l/ext-ctrls-codec-stateless.rst | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst index 6541e4c32b26..bee73065e993 100644 --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst @@ -649,10 +649,16 @@ Stateless Codec Control ID :c:type:`timeval` in struct :c:type:`v4l2_buffer` to a __u64. * - __u32 - ``pic_num`` - - + - For short term references, this must match the derived value PicNum + (8-28) and for long term references it must match the derived value + LongTermPicNum (8-29). When decoding frames (as opposed to fields) + pic_num is the same as FrameNumWrap. * - __u16 - ``frame_num`` - - + - For short term references, this must match the frame_num value from + the slice header syntax (the driver will wrap the value if needed). For + long term references, this must be set to the value of + long_term_frame_idx described in the dec_ref_pic_marking() syntax. * - __u8 - ``fields`` - Specifies how the DPB entry is referenced. See :ref:`Reference Fields `