From patchwork Sat Mar 26 21:39:26 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Sebastian Fricke X-Patchwork-Id: 12792691 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 239B0C433EF for ; Sat, 26 Mar 2022 21:41:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=fpbA8FoKr9Bx5u3+znpy4UbiSoRiiiKwciQgJkAXu8U=; b=Z96LFYUBVVt8ju lJ006+ShDHG3lRvNBXdOCQ+iwrJyioXZus05GXvvW93awNwf1+nQRf9i6lHWmJVT7pK+0mhVASpor LsJISGGsZAfk0y2zOBrMnNXRUr6f5iccriDV1q5fCpfblsKXmOXzGnwjDD+fDYWQotSXigP5833Ma QAWVHXhDJxmoR1/6PZtra+fQIYoQMcp40NVJlgfH9fTK+BkY4i2BXO/F9gDD4/GBlm9tjSpF5qZAv QX675wr3HBGueJS9ieKEDe8/cp9oMv6AK6lqCaMUPSB4Ju8WisyfKixJ5JSEGFk0Z79OkLOnQblGP AytkA0W6+85Lsno3Km5g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nYE8a-004xMx-D2; Sat, 26 Mar 2022 21:39:56 +0000 Received: from bhuna.collabora.co.uk ([2a00:1098:0:82:1000:25:2eeb:e3e3]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nYE8R-004xKB-Oc for linux-arm-kernel@lists.infradead.org; Sat, 26 Mar 2022 21:39:49 +0000 Received: from localhost (unknown [IPv6:2a02:3030:b:56bb:fa6d:7c35:3706:d2b9]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: sebastianfricke) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 787CA1F44384; Sat, 26 Mar 2022 21:39:46 +0000 (GMT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1648330786; bh=F1dL3cnXKmAu6Uh9VDcqP6Zx5+Do8cHpp5UctZ443fM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ojUiBLj0Na7MmMoDpmsO5E89JcWI4z60KK0UHE7q9Z2apkPnVKHnkIlApHNM35O3H 3aw+EucxSefUltpMK1uClEHFHltRzn58xV3I5hVkjH8Skv4s4eHdi4aDhvS2W8rrAn tmryxI/CmKJo5ngKnODz0T+fNLzTPZN4P4/6XpLEMUt5jgJS8Ak7qNgPOjtkUHLu63 NyAZmW5qoBDj8zrCXU9r82Oo/Kfigyr49JlCV26/Bpyg4wJMG9DLSRIMr5VCBLF23c XNNhO3qlmQfdtva1wkDUXX7IaBz/eBAeRvBOJhuDTi4P0rNptraLup4iaQzZ1MEPIE eL/0xcmjohyNQ== From: Sebastian Fricke To: linux-media@vger.kernel.org Cc: acourbot@chromium.org, tfiga@chromium.org, hverkuil-cisco@xs4all.nl, Sebastian Fricke , Mauro Carvalho Chehab , Maxime Ripard , Paul Kocialkowski , Greg Kroah-Hartman , Chen-Yu Tsai , Jernej Skrabec , linux-kernel@vger.kernel.org (open list), linux-staging@lists.linux.dev (open list:STAGING SUBSYSTEM), linux-arm-kernel@lists.infradead.org (moderated list:ARM/Allwinner sunXi SoC support), linux-sunxi@lists.linux.dev (open list:ARM/Allwinner sunXi SoC support) Subject: [RFC PATCH v2 1/2] media: docs-rst: Append HEVC specific term Date: Sat, 26 Mar 2022 22:39:26 +0100 Message-Id: <20220326213927.103680-2-sebastian.fricke@collabora.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220326213927.103680-1-sebastian.fricke@collabora.com> References: <20220326213927.103680-1-sebastian.fricke@collabora.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220326_143947_966452_826E9F7F X-CRM114-Status: GOOD ( 12.59 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Describe the coding tree unit as replacement for the macroblock in the HEVC codec. Highlight a key difference of the HEVC codec to predecessors like AVC(H.264) to give a better overview of the differences between the coding standards. Signed-off-by: Sebastian Fricke --- Documentation/userspace-api/media/v4l/dev-decoder.rst | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/Documentation/userspace-api/media/v4l/dev-decoder.rst b/Documentation/userspace-api/media/v4l/dev-decoder.rst index 3cf2b496f2d0..eb5b1b1e3a51 100644 --- a/Documentation/userspace-api/media/v4l/dev-decoder.rst +++ b/Documentation/userspace-api/media/v4l/dev-decoder.rst @@ -72,6 +72,11 @@ coded resolution coded width width for given coded resolution. +coding tree unit + processing unit of the HEVC codec (≘ macroblock units in H.264, VP8, VP9); + can use block structures of up to 64×64 pixels; + Good at sub-partitioning the picture into variable sized structures. + decode order the order in which frames are decoded; may differ from display order if the coded format includes a feature of frame reordering; for decoders, @@ -104,7 +109,8 @@ keyframe macroblock a processing unit in image and video compression formats based on linear block transforms (e.g. H.264, VP8, VP9); codec-specific, but for most of - popular codecs the size is 16x16 samples (pixels). + popular codecs the size is 16x16 samples (pixels). The HEVC codec uses a + slightly more flexible processing unit called coding tree unit (CTU). OUTPUT the source buffer queue; for decoders, the queue of buffers containing