From patchwork Sat Mar 26 18:31:56 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Sebastian Fricke X-Patchwork-Id: 12792662 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 02BFAC433F5 for ; Sat, 26 Mar 2022 18:35:59 +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: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:In-Reply-To:References: List-Owner; bh=fpbA8FoKr9Bx5u3+znpy4UbiSoRiiiKwciQgJkAXu8U=; b=bLIJ9M2fITxvl4 2tJXOtxznxW1/vZDmdPdy0r5GkCFAya3/cCetx+p0YQEk2VTfSEiDcccL4R7wXandU5n7tW/yv+9A 3V/qGAXBuX8HiShXki3GKfE6IoPXft9lQJaVTBk2zVAZeZhgd0aqIAoETyLiTnowE6dk/m30boNET 4F7agfx+M5PHQge3wRpF1NlljN9tish3lhrs3MLqWW4rtos7DET01QN1b5mYcKTjOxRlWtTK/kzpv 7JBCUkx9o1GXkHvE4KzjDK22GiBOQruZc9aAlPbcUDYO7mZQCsr4s5mLmW0Ko7ThdvRJrkLW1qqBV BKQDdRqiqUOdSL1D0sbA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nYBFP-004h7b-EP; Sat, 26 Mar 2022 18:34:47 +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 1nYBEc-004gpM-4W for linux-arm-kernel@lists.infradead.org; Sat, 26 Mar 2022 18:33:59 +0000 Received: from localhost (unknown [IPv6:2a02:3030:b:56bb:4cb:3227:231:99f8]) (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 BF73D1F40C70; Sat, 26 Mar 2022 18:33:53 +0000 (GMT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1648319634; bh=F1dL3cnXKmAu6Uh9VDcqP6Zx5+Do8cHpp5UctZ443fM=; h=From:To:Cc:Subject:Date:From; b=Dxe0Qk5GLqgaLCfU5869zJs3CanLcbpKDStnNBpn/1VUNfJzXIFw0Mzq6k2xvlqLA ZhXyINNAS71xfREVRlKs5ZZTcDgtolqf+43qhhtPSiKH7EvVAeO2jer/dyBRYIP6JH fBcVXPQRHjU3Ma6BKtUUenq5DCoXwpZ672xN+91rVyvS5/1r/f5sB7AsJzJp/MSm8L wlpJ38EmUOK08YUxTCAa9ZGqaL6f4GfQBT2+yt+ukhCuQxM4aKKXXPandP11VZDMIp UwaE5gQDxuMsFMEU3pxJhhqjeP4yc/c4FkFN4MY9dOpZEiicTCttJqAX+GnXkI4Rgj yQLSnOO6U4EYw== 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 1/2] media: docs-rst: Append HEVC specific term Date: Sat, 26 Mar 2022 19:31:56 +0100 Message-Id: <20220326183158.65303-1-sebastian.fricke@collabora.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220326_113358_473683_59DD5473 X-CRM114-Status: GOOD ( 12.10 ) 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