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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E6803C433EF for ; Tue, 23 Nov 2021 10:24:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235304AbhKWK1K (ORCPT ); Tue, 23 Nov 2021 05:27:10 -0500 Received: from mga02.intel.com ([134.134.136.20]:51540 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231838AbhKWK1J (ORCPT ); Tue, 23 Nov 2021 05:27:09 -0500 X-IronPort-AV: E=McAfee;i="6200,9189,10176"; a="222218952" X-IronPort-AV: E=Sophos;i="5.87,257,1631602800"; d="scan'208";a="222218952" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Nov 2021 02:24:01 -0800 X-IronPort-AV: E=Sophos;i="5.87,257,1631602800"; d="scan'208";a="571020561" Received: from paasikivi.fi.intel.com ([10.237.72.42]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Nov 2021 02:23:58 -0800 Received: from paasikivi.fi.intel.com (localhost [127.0.0.1]) by paasikivi.fi.intel.com (Postfix) with ESMTP id 3A09A20762; Tue, 23 Nov 2021 12:23:56 +0200 (EET) Date: Tue, 23 Nov 2021 12:23:56 +0200 From: Sakari Ailus To: Jammy Huang Cc: "eajames@linux.ibm.com" , "mchehab@kernel.org" , "joel@jms.id.au" , "andrew@aj.id.au" , "hverkuil-cisco@xs4all.nl" , "gregkh@linuxfoundation.org" , "laurent.pinchart@ideasonboard.com" , "linux-media@vger.kernel.org" , "openbmc@lists.ozlabs.org" , "linux-arm-kernel@lists.infradead.org" , "linux-aspeed@lists.ozlabs.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v5 05/10] media: v4l: Add definition for the Aspeed JPEG format Message-ID: References: <20211118074030.685-1-jammy_huang@aspeedtech.com> <20211118074030.685-6-jammy_huang@aspeedtech.com> <0bed6093-0af6-4fc4-716f-6cf8b1302320@aspeedtech.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <0bed6093-0af6-4fc4-716f-6cf8b1302320@aspeedtech.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jammy, On Fri, Nov 19, 2021 at 10:02:40AM +0800, Jammy Huang wrote: > Hi Sakari, > > On 2021/11/18 下午 08:33, Sakari Ailus wrote: > > Hi Jammy, > > > > On Thu, Nov 18, 2021 at 03:40:26PM +0800, Jammy Huang wrote: > > > This introduces support for the Aspeed JPEG format, where the new frame > > > can refer to previous frame to reduce the amount of compressed data. The > > > concept is similar to I/P frame of video compression. I will compare the > > > new frame with previous one to decide which macroblock's data is > > > changed, and only the changed macroblocks will be compressed. > > > > > > This Aspeed JPEG format is used by the video engine on Aspeed platforms, > > > which is generally adapted for remote KVM. > > > > > > Signed-off-by: Jammy Huang > > > --- > > > v5: > > > - no update > > > v4: > > > - new > > > --- > > > Documentation/media/uapi/v4l/pixfmt-reserved.rst | 12 ++++++++++++ > > > drivers/media/v4l2-core/v4l2-ioctl.c | 1 + > > > include/uapi/linux/videodev2.h | 1 + > > > 3 files changed, 14 insertions(+) > > > > > > diff --git a/Documentation/media/uapi/v4l/pixfmt-reserved.rst b/Documentation/media/uapi/v4l/pixfmt-reserved.rst > > > index b2cd155e691b..23c05063133d 100644 > > > --- a/Documentation/media/uapi/v4l/pixfmt-reserved.rst > > > +++ b/Documentation/media/uapi/v4l/pixfmt-reserved.rst > > > @@ -264,6 +264,18 @@ please make a proposal on the linux-media mailing list. > > > of tiles, resulting in 32-aligned resolutions for the luminance plane > > > and 16-aligned resolutions for the chrominance plane (with 2x2 > > > subsampling). > > > + * .. _V4L2-PIX-FMT-AJPG: > > > + > > > + - ``V4L2_PIX_FMT_AJPG`` > > > + - 'AJPG' > > > + - ASPEED JPEG format used by the aspeed-video driver on Aspeed platforms, > > > + which is generally adapted for remote KVM. > > > + On each frame compression, I will compare the new frame with previous > > > + one to decide which macroblock's data is changed, and only the changed > > > + macroblocks will be compressed. > > > + > > > + You could reference to chapter 36, Video Engine, of AST2600's datasheet > > > + for more information. > > Is this datasheet publicly available? Do you have a URL? > > Sorry, this datasheet is not publicly available. > Hans mentioned this as well in the discussion below: > > https://lkml.org/lkml/2021/11/10/101 If the vendor documentation is not publicly available, you'll need to have the format documented here. Alternatively an open source implementation (e.g. LGPL) is presumably fine, too. -- Regards, Sakari Ailus 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 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 6D84CC433EF for ; Tue, 23 Nov 2021 10:27:41 +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:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=9/zFAm/hGnlhWHPFX2280Jye8+tTW7EDzI9EnpHI16Q=; 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23 Nov 2021 02:24:01 -0800 X-IronPort-AV: E=Sophos;i="5.87,257,1631602800"; d="scan'208";a="571020561" Received: from paasikivi.fi.intel.com ([10.237.72.42]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Nov 2021 02:23:58 -0800 Received: from paasikivi.fi.intel.com (localhost [127.0.0.1]) by paasikivi.fi.intel.com (Postfix) with ESMTP id 3A09A20762; Tue, 23 Nov 2021 12:23:56 +0200 (EET) Date: Tue, 23 Nov 2021 12:23:56 +0200 From: Sakari Ailus To: Jammy Huang Cc: "eajames@linux.ibm.com" , "mchehab@kernel.org" , "joel@jms.id.au" , "andrew@aj.id.au" , "hverkuil-cisco@xs4all.nl" , "gregkh@linuxfoundation.org" , "laurent.pinchart@ideasonboard.com" , "linux-media@vger.kernel.org" , "openbmc@lists.ozlabs.org" , "linux-arm-kernel@lists.infradead.org" , "linux-aspeed@lists.ozlabs.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v5 05/10] media: v4l: Add definition for the Aspeed JPEG format Message-ID: References: <20211118074030.685-1-jammy_huang@aspeedtech.com> <20211118074030.685-6-jammy_huang@aspeedtech.com> <0bed6093-0af6-4fc4-716f-6cf8b1302320@aspeedtech.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <0bed6093-0af6-4fc4-716f-6cf8b1302320@aspeedtech.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211123_022603_911560_847E195F X-CRM114-Status: GOOD ( 29.11 ) 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: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org SGkgSmFtbXksCgpPbiBGcmksIE5vdiAxOSwgMjAyMSBhdCAxMDowMjo0MEFNICswODAwLCBKYW1t eSBIdWFuZyB3cm90ZToKPiBIaSBTYWthcmksCj4gCj4gT24gMjAyMS8xMS8xOCDkuIvljYggMDg6 MzMsIFNha2FyaSBBaWx1cyB3cm90ZToKPiA+IEhpIEphbW15LAo+ID4gCj4gPiBPbiBUaHUsIE5v diAxOCwgMjAyMSBhdCAwMzo0MDoyNlBNICswODAwLCBKYW1teSBIdWFuZyB3cm90ZToKPiA+ID4g VGhpcyBpbnRyb2R1Y2VzIHN1cHBvcnQgZm9yIHRoZSBBc3BlZWQgSlBFRyBmb3JtYXQsIHdoZXJl IHRoZSBuZXcgZnJhbWUKPiA+ID4gY2FuIHJlZmVyIHRvIHByZXZpb3VzIGZyYW1lIHRvIHJlZHVj ZSB0aGUgYW1vdW50IG9mIGNvbXByZXNzZWQgZGF0YS4gVGhlCj4gPiA+IGNvbmNlcHQgaXMgc2lt aWxhciB0byBJL1AgZnJhbWUgb2YgdmlkZW8gY29tcHJlc3Npb24uIEkgd2lsbCBjb21wYXJlIHRo ZQo+ID4gPiBuZXcgZnJhbWUgd2l0aCBwcmV2aW91cyBvbmUgdG8gZGVjaWRlIHdoaWNoIG1hY3Jv YmxvY2sncyBkYXRhIGlzCj4gPiA+IGNoYW5nZWQsIGFuZCBvbmx5IHRoZSBjaGFuZ2VkIG1hY3Jv YmxvY2tzIHdpbGwgYmUgY29tcHJlc3NlZC4KPiA+ID4gCj4gPiA+IFRoaXMgQXNwZWVkIEpQRUcg Zm9ybWF0IGlzIHVzZWQgYnkgdGhlIHZpZGVvIGVuZ2luZSBvbiBBc3BlZWQgcGxhdGZvcm1zLAo+ ID4gPiB3aGljaCBpcyBnZW5lcmFsbHkgYWRhcHRlZCBmb3IgcmVtb3RlIEtWTS4KPiA+ID4gCj4g PiA+IFNpZ25lZC1vZmYtYnk6IEphbW15IEh1YW5nIDxqYW1teV9odWFuZ0Bhc3BlZWR0ZWNoLmNv bT4KPiA+ID4gLS0tCj4gPiA+IHY1Ogo+ID4gPiAgICAtIG5vIHVwZGF0ZQo+ID4gPiB2NDoKPiA+ ID4gICAgLSBuZXcKPiA+ID4gLS0tCj4gPiA+ICAgRG9jdW1lbnRhdGlvbi9tZWRpYS91YXBpL3Y0 bC9waXhmbXQtcmVzZXJ2ZWQucnN0IHwgMTIgKysrKysrKysrKysrCj4gPiA+ICAgZHJpdmVycy9t ZWRpYS92NGwyLWNvcmUvdjRsMi1pb2N0bC5jICAgICAgICAgICAgIHwgIDEgKwo+ID4gPiAgIGlu Y2x1ZGUvdWFwaS9saW51eC92aWRlb2RldjIuaCAgICAgICAgICAgICAgICAgICB8ICAxICsKPiA+ ID4gICAzIGZpbGVzIGNoYW5nZWQsIDE0IGluc2VydGlvbnMoKykKPiA+ID4gCj4gPiA+IGRpZmYg LS1naXQgYS9Eb2N1bWVudGF0aW9uL21lZGlhL3VhcGkvdjRsL3BpeGZtdC1yZXNlcnZlZC5yc3Qg Yi9Eb2N1bWVudGF0aW9uL21lZGlhL3VhcGkvdjRsL3BpeGZtdC1yZXNlcnZlZC5yc3QKPiA+ID4g aW5kZXggYjJjZDE1NWU2OTFiLi4yM2MwNTA2MzEzM2QgMTAwNjQ0Cj4gPiA+IC0tLSBhL0RvY3Vt ZW50YXRpb24vbWVkaWEvdWFwaS92NGwvcGl4Zm10LXJlc2VydmVkLnJzdAo+ID4gPiArKysgYi9E b2N1bWVudGF0aW9uL21lZGlhL3VhcGkvdjRsL3BpeGZtdC1yZXNlcnZlZC5yc3QKPiA+ID4gQEAg LTI2NCw2ICsyNjQsMTggQEAgcGxlYXNlIG1ha2UgYSBwcm9wb3NhbCBvbiB0aGUgbGludXgtbWVk aWEgbWFpbGluZyBsaXN0Lgo+ID4gPiAgIAlvZiB0aWxlcywgcmVzdWx0aW5nIGluIDMyLWFsaWdu ZWQgcmVzb2x1dGlvbnMgZm9yIHRoZSBsdW1pbmFuY2UgcGxhbmUKPiA+ID4gICAJYW5kIDE2LWFs aWduZWQgcmVzb2x1dGlvbnMgZm9yIHRoZSBjaHJvbWluYW5jZSBwbGFuZSAod2l0aCAyeDIKPiA+ ID4gICAJc3Vic2FtcGxpbmcpLgo+ID4gPiArICAgICogLi4gX1Y0TDItUElYLUZNVC1BSlBHOgo+ ID4gPiArCj4gPiA+ICsgICAgICAtIGBgVjRMMl9QSVhfRk1UX0FKUEdgYAo+ID4gPiArICAgICAg LSAnQUpQRycKPiA+ID4gKyAgICAgIC0gQVNQRUVEIEpQRUcgZm9ybWF0IHVzZWQgYnkgdGhlIGFz cGVlZC12aWRlbyBkcml2ZXIgb24gQXNwZWVkIHBsYXRmb3JtcywKPiA+ID4gKyAgICAgICAgd2hp Y2ggaXMgZ2VuZXJhbGx5IGFkYXB0ZWQgZm9yIHJlbW90ZSBLVk0uCj4gPiA+ICsgICAgICAgIE9u IGVhY2ggZnJhbWUgY29tcHJlc3Npb24sIEkgd2lsbCBjb21wYXJlIHRoZSBuZXcgZnJhbWUgd2l0 aCBwcmV2aW91cwo+ID4gPiArICAgICAgICBvbmUgdG8gZGVjaWRlIHdoaWNoIG1hY3JvYmxvY2sn cyBkYXRhIGlzIGNoYW5nZWQsIGFuZCBvbmx5IHRoZSBjaGFuZ2VkCj4gPiA+ICsgICAgICAgIG1h Y3JvYmxvY2tzIHdpbGwgYmUgY29tcHJlc3NlZC4KPiA+ID4gKwo+ID4gPiArICAgICAgICBZb3Ug Y291bGQgcmVmZXJlbmNlIHRvIGNoYXB0ZXIgMzYsIFZpZGVvIEVuZ2luZSwgb2YgQVNUMjYwMCdz IGRhdGFzaGVldAo+ID4gPiArICAgICAgICBmb3IgbW9yZSBpbmZvcm1hdGlvbi4KPiA+IElzIHRo aXMgZGF0YXNoZWV0IHB1YmxpY2x5IGF2YWlsYWJsZT8gRG8geW91IGhhdmUgYSBVUkw/Cj4gCj4g U29ycnksIHRoaXMgZGF0YXNoZWV0IGlzIG5vdCBwdWJsaWNseSBhdmFpbGFibGUuCj4gSGFucyBt ZW50aW9uZWQgdGhpcyBhcyB3ZWxsIGluIHRoZSBkaXNjdXNzaW9uIGJlbG93Ogo+IAo+IGh0dHBz Oi8vbGttbC5vcmcvbGttbC8yMDIxLzExLzEwLzEwMQoKSWYgdGhlIHZlbmRvciBkb2N1bWVudGF0 aW9uIGlzIG5vdCBwdWJsaWNseSBhdmFpbGFibGUsIHlvdSdsbCBuZWVkIHRvIGhhdmUKdGhlIGZv cm1hdCBkb2N1bWVudGVkIGhlcmUuIEFsdGVybmF0aXZlbHkgYW4gb3BlbiBzb3VyY2UgaW1wbGVt ZW50YXRpb24KKGUuZy4gTEdQTCkgaXMgcHJlc3VtYWJseSBmaW5lLCB0b28uCgotLSAKUmVnYXJk cywKClNha2FyaSBBaWx1cwoKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX18KbGludXgtYXJtLWtlcm5lbCBtYWlsaW5nIGxpc3QKbGludXgtYXJtLWtlcm5lbEBs aXN0cy5pbmZyYWRlYWQub3JnCmh0dHA6Ly9saXN0cy5pbmZyYWRlYWQub3JnL21haWxtYW4vbGlz dGluZm8vbGludXgtYXJtLWtlcm5lbAo= 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 Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (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 CF31CC433EF for ; Tue, 23 Nov 2021 10:28:31 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4Hz0jB3sbXz3gc8 for ; Tue, 23 Nov 2021 21:28:30 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=linux.intel.com (client-ip=134.134.136.20; helo=mga02.intel.com; envelope-from=sakari.ailus@linux.intel.com; receiver=) X-Greylist: delayed 124 seconds by postgrey-1.36 at boromir; Tue, 23 Nov 2021 21:27:09 AEDT Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4Hz0gd4n5Pz3fpS; Tue, 23 Nov 2021 21:27:09 +1100 (AEDT) X-IronPort-AV: E=McAfee;i="6200,9189,10176"; a="222218953" X-IronPort-AV: E=Sophos;i="5.87,257,1631602800"; d="scan'208";a="222218953" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Nov 2021 02:24:01 -0800 X-IronPort-AV: E=Sophos;i="5.87,257,1631602800"; d="scan'208";a="571020561" Received: from paasikivi.fi.intel.com ([10.237.72.42]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Nov 2021 02:23:58 -0800 Received: from paasikivi.fi.intel.com (localhost [127.0.0.1]) by paasikivi.fi.intel.com (Postfix) with ESMTP id 3A09A20762; Tue, 23 Nov 2021 12:23:56 +0200 (EET) Date: Tue, 23 Nov 2021 12:23:56 +0200 From: Sakari Ailus To: Jammy Huang Subject: Re: [PATCH v5 05/10] media: v4l: Add definition for the Aspeed JPEG format Message-ID: References: <20211118074030.685-1-jammy_huang@aspeedtech.com> <20211118074030.685-6-jammy_huang@aspeedtech.com> <0bed6093-0af6-4fc4-716f-6cf8b1302320@aspeedtech.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <0bed6093-0af6-4fc4-716f-6cf8b1302320@aspeedtech.com> X-BeenThere: openbmc@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development list for OpenBMC List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "linux-aspeed@lists.ozlabs.org" , "andrew@aj.id.au" , "gregkh@linuxfoundation.org" , "openbmc@lists.ozlabs.org" , "eajames@linux.ibm.com" , "linux-media@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "hverkuil-cisco@xs4all.nl" , "mchehab@kernel.org" , "linux-arm-kernel@lists.infradead.org" , "laurent.pinchart@ideasonboard.com" Errors-To: openbmc-bounces+openbmc=archiver.kernel.org@lists.ozlabs.org Sender: "openbmc" Hi Jammy, On Fri, Nov 19, 2021 at 10:02:40AM +0800, Jammy Huang wrote: > Hi Sakari, > > On 2021/11/18 下午 08:33, Sakari Ailus wrote: > > Hi Jammy, > > > > On Thu, Nov 18, 2021 at 03:40:26PM +0800, Jammy Huang wrote: > > > This introduces support for the Aspeed JPEG format, where the new frame > > > can refer to previous frame to reduce the amount of compressed data. The > > > concept is similar to I/P frame of video compression. I will compare the > > > new frame with previous one to decide which macroblock's data is > > > changed, and only the changed macroblocks will be compressed. > > > > > > This Aspeed JPEG format is used by the video engine on Aspeed platforms, > > > which is generally adapted for remote KVM. > > > > > > Signed-off-by: Jammy Huang > > > --- > > > v5: > > > - no update > > > v4: > > > - new > > > --- > > > Documentation/media/uapi/v4l/pixfmt-reserved.rst | 12 ++++++++++++ > > > drivers/media/v4l2-core/v4l2-ioctl.c | 1 + > > > include/uapi/linux/videodev2.h | 1 + > > > 3 files changed, 14 insertions(+) > > > > > > diff --git a/Documentation/media/uapi/v4l/pixfmt-reserved.rst b/Documentation/media/uapi/v4l/pixfmt-reserved.rst > > > index b2cd155e691b..23c05063133d 100644 > > > --- a/Documentation/media/uapi/v4l/pixfmt-reserved.rst > > > +++ b/Documentation/media/uapi/v4l/pixfmt-reserved.rst > > > @@ -264,6 +264,18 @@ please make a proposal on the linux-media mailing list. > > > of tiles, resulting in 32-aligned resolutions for the luminance plane > > > and 16-aligned resolutions for the chrominance plane (with 2x2 > > > subsampling). > > > + * .. _V4L2-PIX-FMT-AJPG: > > > + > > > + - ``V4L2_PIX_FMT_AJPG`` > > > + - 'AJPG' > > > + - ASPEED JPEG format used by the aspeed-video driver on Aspeed platforms, > > > + which is generally adapted for remote KVM. > > > + On each frame compression, I will compare the new frame with previous > > > + one to decide which macroblock's data is changed, and only the changed > > > + macroblocks will be compressed. > > > + > > > + You could reference to chapter 36, Video Engine, of AST2600's datasheet > > > + for more information. > > Is this datasheet publicly available? Do you have a URL? > > Sorry, this datasheet is not publicly available. > Hans mentioned this as well in the discussion below: > > https://lkml.org/lkml/2021/11/10/101 If the vendor documentation is not publicly available, you'll need to have the format documented here. Alternatively an open source implementation (e.g. LGPL) is presumably fine, too. -- Regards, Sakari Ailus