From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nicolas Dufresne Subject: Re: [PATCH v3 3/9] DocBook/v4l: Add compressed video formats used on MT8173 codec driver Date: Tue, 12 Jul 2016 15:08:31 -0400 Message-ID: <1468350511.8843.16.camel@gmail.com> References: <1464611363-14936-1-git-send-email-tiffany.lin@mediatek.com> <1464611363-14936-2-git-send-email-tiffany.lin@mediatek.com> <1464611363-14936-3-git-send-email-tiffany.lin@mediatek.com> <1464611363-14936-4-git-send-email-tiffany.lin@mediatek.com> <5a793171-24a7-4e9e-8bfd-f668c789f8e0@xs4all.nl> <1468205771.3725.8.camel@mtksdaap41> Reply-To: nicolas@ndufresne.ca Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Wu-Cheng Li =?UTF-8?Q?=28=E6=9D=8E=E5=8B=99=E8=AA=A0=29?= , tiffany lin Cc: Hans Verkuil , Hans Verkuil , Daniel Thompson , Rob Herring , Mauro Carvalho Chehab , Matthias Brugger , Daniel Kurtz , Pawel Osciak , Eddie Huang , Yingjoe Chen , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org, linux-mediatek@lists.infradead.org, Lin PoChun List-Id: devicetree@vger.kernel.org Le mardi 12 juillet 2016 =C3=A0 16:16 +0800, Wu-Cheng Li (=E6=9D=8E=E5=8B= =99=E8=AA=A0) a =C3=A9crit=C2=A0: > Decoder hardware produces MT21 (compressed). Image processor can > convert it to a format that can be input of display driver. Tiffany. > When do you plan to upstream image processor (mtk-mdp)? > > > > It can be as input format for encoder, MDP and display drivers in > our > > platform. > I remember display driver can only accept uncompressed MT21. Right? > Basically V4L2_PIX_FMT_MT21 is compressed and is like an opaque > format. It's not usable until it's decompressed and converted by > image > processor. Previously it was described as MediaTek block mode, and now as a MediaTek compressed format. It makes me think you have no idea what this pixel format really is. Is that right ? The main reason why I keep asking, is that we often find similarities between what vendor like to call their proprietary formats. Doing the proper research helps not creating a mess like in Android where you have a lot of formats that all point to the same format. I believe there was the same concern when Samsung wanted to introduce their Z- flip-Z NV12 tile format. In the end they simply provided sufficient documentation so we could document it and implement software converters for test and validation purpose. regards, Nicolas