From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=kO+RA2EeUG+kJ+3H8+VLgihHja3Gzy7g0bVn6j0SErQ=; b=s/kzwVHCO6ivqUSoWphDUkcZnyvHzufln/wWmsvO/tCJfVwpeiah3hNKvpVcjntO2i YlYmNQqS9nY9qnjUvRjpd8a9pVdfjl0cHehhy4PikoofKJ37s2ACTFFA85g7j9HC86UA /N0tpyiIwSxAlVDbLAWuTdozItdlQicRDPbujHHcyvh2XoLgqi5CjjmKpaF3o6AhRT8M RUltyce0DEn9SeAawT2a6SLoxMY9+//eqfjwbWN5NAjV4G/rWaz3e8VoE6k/S9U/BLFZ qVC4COtVWE/KCnMRcl4uxZWBofnKPhdyogEB2QgT+5vl0mqkFSlftdQhul92VhgwJMId yFKw== References: <8c101e3b-2f80-666c-db86-05b7dd170a7c@gmail.com> <29E8A83D-5BBB-49AA-83A6-4B3EB765828A@msweet.org> <9db67beb-7ca2-249c-88e4-ead29d19ce63@gmail.com> <1501D827-9DF0-45D4-87C6-FB9953C7BF1B@msweet.org> <1a37c322-5ca3-727b-583f-2b6bc78e44e2@gmail.com> <663F1B36-C6A5-4261-8226-C659DC8DA871@msweet.org> From: Till Kamppeter Message-ID: <11635c5c-deaf-94af-012e-36717fd6900e@gmail.com> Date: Sun, 9 May 2021 21:26:09 +0200 MIME-Version: 1.0 In-Reply-To: <663F1B36-C6A5-4261-8226-C659DC8DA871@msweet.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Printing-architecture] Make use of extended color spaces on IPP printers List-Id: Printing architecture under linux List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Michael Sweet Cc: "printing-architecture@lists.linux-foundation.org" , Jay Berkenbilt , Vikrant Malik On 09/05/2021 15:41, Michael Sweet wrote: > >> Now for DeviceRGB (and DeviceGray) I assume that here the data is required in the printer's native color space. Am I right? But can I do true driverless printing with this? Can I download the printer's ICC profiles from the printer? And if yes, by which URL? > > So printers that support device RGB and device gray also support the "printer-icc-profiles" attribute, which allows you to determine which profile to use for a particular combination of Job Template attributes. In some cases a single profile is reported that represents the printer's internal working color space. Unfortunately, this is not always the case. My HP OfficeJet Pro 8730 has the following attributes urf-supported (1setOf keyword) = CP1,MT1-2-8-9-10-11,PQ3-4-5,RS300-600,SRGB24,OB10,W8,DEVW8,DEVRGB24,ADOBERGB24,DM3,FN3,IS1-2,V1.4pwg-raster-document-type-supported (1setOf keyword) = sgray_8,srgb_8,adobe-rgb_8,rgb_8 but no "printer-icc-profiles" attribute. So for Apple Raster it supports Device Gray and Device RGB and for PWG Raster input it supports at least Device RGB ("rgb_8"?), but there is no information about how to download the appropriate ICC profiles from the printer, meaning that these device color spaces are unusable for true driverless printing. Am I right? Till