gimp-print-devel

[Gimp-print-devel] Regarding building and usage of Gimp-print and Android

[Adhiti S. <toa...@gm...>]

Hi Gimp team,

I am trying to support USB printing on Android. Need info on below items to
proceed further.

1> Steps to build Gutenprint source for Android (I am using Android 10).
2> Further I need to integrate as part of the NDK app and use it. Regarding
this, I would like to know if there is a developer guide that I could
follow.

Thanks,
Adhiti

Re: [Gimp-print-devel] Gimp-Print for M1 Big Slur iMac drivers?

[Matt B. <wal...@ma...>]

> On Jun 30, 2021, at 7:26 AM, Matt Broughton <wal...@ma...> wrote:
> 
> 
> 
>> On Jun 28, 2021, at 6:01 AM, Danny Chiu via Gimp-print-devel <gim...@li...> wrote:
>> 
>> Hi Guys,
>> 
>> Any chance you guys will be adding M1 Support?  I’m having problems with my older Canon MG6270 Printer on Big Slur.  It can use “Air Print” to print but the Image Capture, doesn’t see the scanner. 
>> 
>> Thanks,
>> Danny
> 
> Gutenprint does have plans to release a version that is native to the M1 chip.  The current Mac release does work however with the M1 chip as long as Rosetta is installed.  Sorry to say that Gutenprint does not support scanners.
> 
> Matt


Addendum.  I tried Image Capture with my Epson three in one on Intel chipset.   I don't think that Image Capture is designed to work with  a scanner to print directly or automatically.  It makes a scan and places the file on your hard disk for printing from a different application.  I also ran into problems with Image Capture telling me that there was no document loaded.  I had to set whether the document was on the flatbed or in the document feeder.  I hope this helps.,

Also, you might want to check /Library/Image Capture/TWAIN Data Sources to see if the is an entry for Canon.

Matt

Re: [Gimp-print-devel] Gimp-Print for M1 Big Slur iMac drivers?

[Matt B. <wal...@ma...>]

> On Jun 28, 2021, at 6:01 AM, Danny Chiu via Gimp-print-devel <gim...@li...> wrote:
> 
> Hi Guys,
> 
> Any chance you guys will be adding M1 Support?  I’m having problems with my older Canon MG6270 Printer on Big Slur.  It can use “Air Print” to print but the Image Capture, doesn’t see the scanner. 
> 
> Thanks,
> Danny

Gutenprint does have plans to release a version that is native to the M1 chip.  The current Mac release does work however with the M1 chip as long as Rosetta is installed.  Sorry to say that Gutenprint does not support scanners.

Matt

Re: [Gimp-print-devel] Are dithers multi-shade aware?

[Robert K. <rl...@al...>]

On 6/29/21 9:28 AM, Walker Blackwell wrote:
> Dear devs,
> 
> I’m looking Gutenprint code and trying to determine if each channel is dithered independently of every other channel or if they take into account darker shades as no-go placement-points for lighter shades (or vis versa). 
> 
> Eg: For Vivid Magenta dots, no Light Magenta dots should be printed at the same coordinates. Is this what “masking” is in the code? If each channel is independently dithered I’d be interested in funding per-color channel-aware dithering . . .

It's not as easy as it sounds.  In 4.x (when it was called Gimp-Print), it dithered multiple shades
together by creating "virtual" shades, the product of the drop size and the relative darkness of the
ink.  For some things it worked quite well, but it had some problems that I don't remember off the
top of my head.

With the standard Ordered dither it's very hard to do this, since it's using a fixed mask.  That's
not the best way, but it's very fast and with small-drop, multi-shade inks, it's almost as smooth as
the best error diffusions that we've tried with none of the quirks of the latter.

Raph Levien came up with Even Tone Screening (which I implemented) and later came up with Even
Better Screening (which I didn't; it was rather thorny).  I don't remember whether there's any
handling of multi-shade inks in that.

[Gimp-print-devel] Are dithers multi-shade aware?

[Walker B. <fo...@wa...>]

Dear devs,

I’m looking Gutenprint code and trying to determine if each channel is dithered independently of every other channel or if they take into account darker shades as no-go placement-points for lighter shades (or vis versa). 

Eg: For Vivid Magenta dots, no Light Magenta dots should be printed at the same coordinates. Is this what “masking” is in the code? If each channel is independently dithered I’d be interested in funding per-color channel-aware dithering . . .

Best regards,
Walker

[Gimp-print-devel] Gimp-Print for M1 Big Slur iMac drivers?

[Danny C. <dan...@me...>]

Hi Guys,

Any chance you guys will be adding M1 Support?  I’m having problems with my older Canon MG6270 Printer on Big Slur.  It can use “Air Print” to print but the Image Capture, doesn’t see the scanner. 

Thanks,
Danny

Re: [Gimp-print-devel] Gutenprint does not print on Canon iP-90

[Gernot H. <aik...@gm...>]

On Thu, Jun 24, 2021 at 2:10 PM Jim Morgan <hit...@gm...> wrote:

> *Okay, I'll work on getting that CUPS log tomorrow. It's 22:00 here now. *
>
> *Seems I misspoke, **I checked the drivers at the Canon support site just
> now and they don't make drivers for the iP90 for Linux 64 or 32 bit so my
> comment about using the Linux Canon iP90 driver was in error.*
>

Hi Jim,
No problem! Take your time. Look forward to the logs (at my personal email).
Best regards,
Gernot Hassenpflug


>
> On Wed, Jun 23, 2021 at 9:46 PM Gernot Hassenpflug <aik...@gm...>
> wrote:
>
>> On Thu, Jun 24, 2021 at 2:23 AM Jim Morgan <hit...@gm...> wrote:
>>
>>> *bjc-PIXMA-iP90 *
>>> *Gutenprint V5.3.3 driver doesn't print correctly on my Canon iP-90. *
>>>
>>> *Prints fine in Win10 but not on my Linux Ubuntu 20.04.2 machine using
>>> the Canon driver or the Gutenprint driver.*
>>>
>>
>> Hello Jim,
>> Thank you for the report.
>> I can only speak for the gutenprint driver, although I find it hard to
>> believe that the Canon driver does not work, since that would be the
>> official driver provided by the manufacturer. That leads me to think there
>> might be something else going on.
>> I believe that the iP90 should work bascially, given the length of time
>> it has been supported, but there could well be bugs.
>>
>> *Symptoms are familiar to me (but with other printers):*
>>>
>>> *Test print outputs numerous pages with a fine line at the very top of
>>> most and usually a couple pages with a  slightly heavier colored line.*
>>> *But the rest of each page is blank. Usually the printer outputs 10-14
>>> pages printing that slight line at the top of each page.*
>>>
>>
>> Can you set the logging to debug in CUPS, including suiteable maximum log
>> site (unlimited would be good maybe), and then print using a monochrome
>> resolution setting (not automatic) and grayscale, on plain media. That
>> would be the simplest test. You can send me the logfile as a zipped
>> attachment directly (not to the mailing list).
>>
>> Best regards,
>> Gernot Hassenpflug
>>
>>
>
> --
>
>
> *Jim@HiTekVisit my RV travel & repair bloghttp://chaos.goblinbox.com
> <http://chaos.goblinbox.com>*
>


-- 
Protea Wines Japan
Tel: 070-5550-9076
https://www.proteawines.jp

Re: [Gimp-print-devel] Gutenprint does not print on Canon iP-90

[Jim M. <hit...@gm...>]

*Okay, I'll work on getting that CUPS log tomorrow. It's 22:00 here now. *

*Seems I misspoke, **I checked the drivers at the Canon support site just
now and they don't make drivers for the iP90 for Linux 64 or 32 bit so my
comment about using the Linux Canon iP90 driver was in error.*


On Wed, Jun 23, 2021 at 9:46 PM Gernot Hassenpflug <aik...@gm...>
wrote:

> On Thu, Jun 24, 2021 at 2:23 AM Jim Morgan <hit...@gm...> wrote:
>
>> *bjc-PIXMA-iP90 *
>> *Gutenprint V5.3.3 driver doesn't print correctly on my Canon iP-90. *
>>
>> *Prints fine in Win10 but not on my Linux Ubuntu 20.04.2 machine using
>> the Canon driver or the Gutenprint driver.*
>>
>
> Hello Jim,
> Thank you for the report.
> I can only speak for the gutenprint driver, although I find it hard to
> believe that the Canon driver does not work, since that would be the
> official driver provided by the manufacturer. That leads me to think there
> might be something else going on.
> I believe that the iP90 should work bascially, given the length of time it
> has been supported, but there could well be bugs.
>
> *Symptoms are familiar to me (but with other printers):*
>>
>> *Test print outputs numerous pages with a fine line at the very top of
>> most and usually a couple pages with a  slightly heavier colored line.*
>> *But the rest of each page is blank. Usually the printer outputs 10-14
>> pages printing that slight line at the top of each page.*
>>
>
> Can you set the logging to debug in CUPS, including suiteable maximum log
> site (unlimited would be good maybe), and then print using a monochrome
> resolution setting (not automatic) and grayscale, on plain media. That
> would be the simplest test. You can send me the logfile as a zipped
> attachment directly (not to the mailing list).
>
> Best regards,
> Gernot Hassenpflug
>
>

-- 


*Jim@HiTekVisit my RV travel & repair bloghttp://chaos.goblinbox.com
<http://chaos.goblinbox.com>*

Re: [Gimp-print-devel] Gutenprint does not print on Canon iP-90

[Gernot H. <aik...@gm...>]

On Thu, Jun 24, 2021 at 2:23 AM Jim Morgan <hit...@gm...> wrote:

> *bjc-PIXMA-iP90 *
> *Gutenprint V5.3.3 driver doesn't print correctly on my Canon iP-90. *
>
> *Prints fine in Win10 but not on my Linux Ubuntu 20.04.2 machine using the
> Canon driver or the Gutenprint driver.*
>

Hello Jim,
Thank you for the report.
I can only speak for the gutenprint driver, although I find it hard to
believe that the Canon driver does not work, since that would be the
official driver provided by the manufacturer. That leads me to think there
might be something else going on.
I believe that the iP90 should work bascially, given the length of time it
has been supported, but there could well be bugs.

*Symptoms are familiar to me (but with other printers):*
>
> *Test print outputs numerous pages with a fine line at the very top of
> most and usually a couple pages with a  slightly heavier colored line.*
> *But the rest of each page is blank. Usually the printer outputs 10-14
> pages printing that slight line at the top of each page.*
>

Can you set the logging to debug in CUPS, including suiteable maximum log
site (unlimited would be good maybe), and then print using a monochrome
resolution setting (not automatic) and grayscale, on plain media. That
would be the simplest test. You can send me the logfile as a zipped
attachment directly (not to the mailing list).

Best regards,
Gernot Hassenpflug

[Gimp-print-devel] Gutenprint does not print on Canon iP-90

[Jim M. <hit...@gm...>]

*bjc-PIXMA-iP90 *
*Gutenprint V5.3.3 driver doesn't print correctly on my Canon iP-90. *

*Prints fine in Win10 but not on my Linux Ubuntu 20.04.2 machine using the
Canon driver or the Gutenprint driver.*

*Symptoms are familiar to me (but with other printers):*

*Test print outputs numerous pages with a fine line at the very top of most
and usually a couple pages with a  slightly heavier colored line.*
*But the rest of each page is blank. Usually the printer outputs 10-14
pages printing that slight line at the top of each page.*

*Thanks for any help you can provide.  *


-- 


*Jim@HiTekVisit my RV travel & repair bloghttp://chaos.goblinbox.com
<http://chaos.goblinbox.com>*

Re: [Gimp-print-devel] Samsung CLP 300 support in Gutenprint

[Matt B. <wal...@ma...>]

> On Jun 15, 2021, at 10:14 AM, Tyler Durden <tyl...@gm...> wrote:
> 
> Hi
> 
> Is there any way to get support for Samsung CLP-300 in Gutenprint in future version?
> 
> And anyway to get this printer to working now?
> 
> I need to use the pinter on Mac OS Big Sur.

This printer uses printer code that Samsung developed for many of their printers.  It is not a common set of commands.  Gutenprint does not have anyone to develop a compatible code, therefore, Gutenprint will not be providing drivers for this.  I did notice that Samsung provided Mac drivers through Mac OS X 10.7 only.

Matt

Re: [Gimp-print-devel] Epson P9000

[Walker B. <fo...@wa...>]

I use the 9900 driver with the P9000 and it works.

best
Walker


> On Jun 18, 2021, at 3:15 PM, CassandraGoad via Gimp-print-devel <gim...@li...> wrote:
> 
> Hello,
>  
> I am a photographer based in the UK and I tried using your printer driver with my Epson P9000 (which your website says is supported but with the label “EXPERIMENTAL”) but the printer would return an error (Ink sets do not match). I think it must be because the P9000 has 10 inks and your driver has a maximum of 8. I tried using the Greyscale setting but that didn’t work either.
>  
> Do you know if there is a way of making it work?
>  
> I’ve heard so many good things about your driver that I am keen to try it.
>  
> Kind regards,
>  
> Erik Wetter
> eri...@ic... <mailto:eri...@ic...>
>  
>  
> _______________________________________________
> Gimp-print-devel mailing list
> Gim...@li... <mailto:Gim...@li...>
> https://lists.sourceforge.net/lists/listinfo/gimp-print-devel <https://lists.sourceforge.net/lists/listinfo/gimp-print-devel>

[Gimp-print-devel] Epson P9000

[CassandraGoad <eri...@me...>]

Hello,

 

I am a photographer based in the UK and I tried using your printer driver with my Epson P9000 (which your website says is supported but with the label “EXPERIMENTAL”) but the printer would return an error (Ink sets do not match). I think it must be because the P9000 has 10 inks and your driver has a maximum of 8. I tried using the Greyscale setting but that didn’t work either.

 

Do you know if there is a way of making it work?

 

I’ve heard so many good things about your driver that I am keen to try it.

 

Kind regards,

 

Erik Wetter

eri...@ic...

 

 

Re: [Gimp-print-devel] install gutenprint

[Robert K. <rl...@al...>]

On 6/15/21 12:48 AM, Ricardo Jasso wrote:
> I would like to subscribe to your letters and emails. I would also like to ask you guys a couple
> questions about gutenprint and if removing my canon printer drivers is the only way to be able to
> print with absolute freedom and NO RESTRICTIONS

You can subscribe to the gimp-print-devel mailing list via
https://lists.sourceforge.net/lists/listinfo/gimp-print-devel

Gutenprint is licensed under the GPL.  This imposes no restrictions of any kind on use; the license
restrictions only come into play if you want to redistribute it to others.

As for whether your printer is supported, you'd have to specify what it is.  Also be aware that we
only support Linux and Macintosh (currently through roughly 10.14); we're having some issues with
Mac support.  We don't support Windows, although anyone who wants to port it is welcome.

[Gimp-print-devel] Samsung CLP 300 support in Gutenprint

[Tyler D. <tyl...@gm...>]

Hi

Is there any way to get support for Samsung CLP-300 in Gutenprint in future version?

And anyway to get this printer to working now?

I need to use the pinter on Mac OS Big Sur.

Re: [Gimp-print-devel] install gutenprint

[Gernot H. <aik...@gm...>]

On Tue, Jun 15, 2021 at 9:44 PM Ricardo Jasso <bit...@ou...>
wrote:

> I would like to subscribe to your letters and emails. I would also like to
> ask you guys a couple questions about gutenprint and if removing my canon
> printer drivers is the only way to be able to print with absolute freedom
> and NO RESTRICTIONS
>

Hi,
Thank you for your interest.
Feel free to ask.
gutenprint also has a license, so you would have to refer to that to see
whether it meeds your needs if the Canon driver license does not.
Most users are concerned about whether they can print from particular
systems, or at specific qualities, or accessing particular options.
So whether gutenprint can do what you want better than the official Canon
driver is dependent on the particular requirement.

Sent from Mail <https://go.microsoft.com/fwlink/?LinkId=550986> for Windows
> 10
>

I should note there is no officially supported gutenprint for Windows.

Best regards,
Gernot Hassenpflug

[Gimp-print-devel] install gutenprint

[Ricardo J. <bit...@ou...>]

I would like to subscribe to your letters and emails. I would also like to ask you guys a couple questions about gutenprint and if removing my canon printer drivers is the only way to be able to print with absolute freedom and NO RESTRICTIONS

Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Windows 10

Re: [Gimp-print-devel] Printer resolution (limits), "native resolution", quality enhancement settings

[Robert K. <rl...@al...>]

On 6/13/21 8:46 PM, Marius Steffen wrote:
> Thanks for your quick answer.
> 
> Now, how would I go about to check, at least in my printer, if there’s any (and how much) benefit
> from printing beyond 2880x2880, and what should I expect?

Try it and see.  If you're printing photos or similar continuous-tone work, it probably won't make
much of a difference, particularly on a printer like the P800 with relatively large drops (3.5 pl)
and 3 shades of gray/black.  If you're printing pure black and white line art, it might, but in that
situation you're better off using a symmetric resolution like 2880x2880 or 1440x1440 rather than one
that isn't (you'll have less moire effect that way).  But if you really need that kind of
resolution, you'd want a printer with extremely small drops.

My own experience printing photos is that on the 3.5 and 4 pl CcMmYKkk printers, even 1440x720 works
very well and is much faster that, say, 2880x1440.

> Also: what’s the ideal resolution to send to the printer, as in pixel resolution, not dithered images?

Anything within reason that's a multiple of the spacing.  720 will give you very crisp text; 360 or
720 is quite ample for photos.  For very intricate line art, again, you'd ideally want to match the
printer resolution.

Re: [Gimp-print-devel] Printer resolution (limits), "native resolution", quality enhancement settings

[Marius S. <ma...@ma...>]

Thanks for your quick answer.

Now, how would I go about to check, at least in my printer, if there’s any (and how much) benefit from printing beyond 2880x2880, and what should I expect?

Also: what’s the ideal resolution to send to the printer, as in pixel resolution, not dithered images?

Marius Steffen
ma...@ma...



> Am 14.06.2021 um 02:15 schrieb Robert Krawitz <rl...@al...>:
> 
> On 6/13/21 4:56 PM, Marius Steffen wrote:
>> Hi,
>> 
>> I’m trying to wrap my head around all the stuff concerning resolution of my Epson P800, or printers
>> in general, hopefully being able to provide some corrections for my printer, as it’s still
>> „EXPERIMENTAL“.
>> 
>> For now, I’m trying to understand:
>> 1) How are the different printing resolutions chosen? Why is there no „5760x5760“ setting, or even
>> higher?
> 
> Based on what the printer can do.  No Epson printer that I know of can actually print 5760 dpi in
> the vertical direction.
> 
>> 2) What’s the limit for printer resolution given, a specific printer? My P800 is listed with a
>> maximum resolution of 2880x1440, how does Gutenprint achieve a higher resolution than this?
> 
> We've determined that some printers can achieve higher resolution that what's specified.  Some
> printers do work perfectly well at such high resolutions; some are iffy.
> 
>> 3) I’ve read some stuff about „native printer resolution“ - as I understand it, that’s the
>> resolution the driver down-/upsamples every raster graphic send to it. How is this chosen for a
>> specific printer in Gutenprint, and why? Do the choice of printing resolution does have any impact
>> on this?
> 
> "Native printer resolution" means whatever resolution the printer is actually set to.  So if you
> specify 5760x1440 dpi, that's the "native printer resolution" for that job.
> 
>> 4) What does the „Quality Enhancement“ setting do, and how is it concerned by printer resolution?
> 
> It breaks up each line of dots into more sub-lines, resulting in longer printing time but possibly
> better quality.  It's most likely to help if you have a bad nozzle or two  Some printers can't
> handle this, especially at already high resolutions.  Each step of quality enhancement doubles
> printing time.  You'll have to experiment to see if it helps; usually it doesn't.
> 
>> Thank you so much in advance for you explanations! :D
> 
> 
> _______________________________________________
> Gimp-print-devel mailing list
> Gim...@li...
> https://lists.sourceforge.net/lists/listinfo/gimp-print-devel

Re: [Gimp-print-devel] Printer resolution (limits), "native resolution", quality enhancement settings

[Robert K. <rl...@al...>]

On 6/13/21 4:56 PM, Marius Steffen wrote:
> Hi,
> 
> I’m trying to wrap my head around all the stuff concerning resolution of my Epson P800, or printers
> in general, hopefully being able to provide some corrections for my printer, as it’s still
> „EXPERIMENTAL“.
> 
> For now, I’m trying to understand:
> 1) How are the different printing resolutions chosen? Why is there no „5760x5760“ setting, or even
> higher?

Based on what the printer can do.  No Epson printer that I know of can actually print 5760 dpi in
the vertical direction.

> 2) What’s the limit for printer resolution given, a specific printer? My P800 is listed with a
> maximum resolution of 2880x1440, how does Gutenprint achieve a higher resolution than this?

We've determined that some printers can achieve higher resolution that what's specified.  Some
printers do work perfectly well at such high resolutions; some are iffy.

> 3) I’ve read some stuff about „native printer resolution“ - as I understand it, that’s the
> resolution the driver down-/upsamples every raster graphic send to it. How is this chosen for a
> specific printer in Gutenprint, and why? Do the choice of printing resolution does have any impact
> on this?

"Native printer resolution" means whatever resolution the printer is actually set to.  So if you
specify 5760x1440 dpi, that's the "native printer resolution" for that job.

> 4) What does the „Quality Enhancement“ setting do, and how is it concerned by printer resolution?

It breaks up each line of dots into more sub-lines, resulting in longer printing time but possibly
better quality.  It's most likely to help if you have a bad nozzle or two  Some printers can't
handle this, especially at already high resolutions.  Each step of quality enhancement doubles
printing time.  You'll have to experiment to see if it helps; usually it doesn't.

> Thank you so much in advance for you explanations! :D

[Gimp-print-devel] Printer resolution (limits), "native resolution", quality enhancement settings

[Marius S. <ma...@ma...>]

Hi,

I’m trying to wrap my head around all the stuff concerning resolution of my Epson P800, or printers in general, hopefully being able to provide some corrections for my printer, as it’s still „EXPERIMENTAL“.

For now, I’m trying to understand:
1) How are the different printing resolutions chosen? Why is there no „5760x5760“ setting, or even higher?
2) What’s the limit for printer resolution given, a specific printer? My P800 is listed with a maximum resolution of 2880x1440, how does Gutenprint achieve a higher resolution than this?
3) I’ve read some stuff about „native printer resolution“ - as I understand it, that’s the resolution the driver down-/upsamples every raster graphic send to it. How is this chosen for a specific printer in Gutenprint, and why? Do the choice of printing resolution does have any impact on this?
4) What does the „Quality Enhancement“ setting do, and how is it concerned by printer resolution?

Thank you so much in advance for you explanations! :D

Marius Steffen
ma...@ma...

Re: [Gimp-print-devel] Translation

[Robert K. <rl...@al...>]

On 6/7/21 3:11 PM, Quentin PAGÈS wrote:
> Hello,
> I'd like to have the pot file so I can send the translation in my language.
> Best regards
> 
> *Quentin PAGÈS*

Hi,

We use the Translation Project (www.translationproject.org) to do our translations.  Please register
there to do it.  Thanks!

[Gimp-print-devel] Translation

[Quentin P. <que...@fr...>]

Hello, 
I'd like to have the pot file so I can send the translation in my language. 
Best regards 


Quentin PAGÈS 

Re: [Gimp-print-devel] Raw input mode via CUPS?

[Robert K. <rl...@al...>]

On 6/4/21 8:21 PM, Marius Steffen wrote:
> Hi everbody,
> 
> I’m currently trying to partially replace Epson’s driver for my SureColor P800 printer. My specific
> reason is the driver’s inability to print CMYK and directly access all the printers ink channels.
> While I found out how to do CMYK prints using Gutenprint, I’m failing to do CcMmYKkk prints with
> files provided in DeviceN space.
>
> I’ve found this rather old message in the mailing list
> archive: https://sourceforge.net/p/gimp-print/mailman/message/19908513/
> <https://sourceforge.net/p/gimp-print/mailman/message/19908513/>
> Essentially, what I’m trying to do is what Robert described in 2) as „raw input with raw color
> correction“, but I’m failing to see how to do that via CUPS - is this even possible, or is one
> forced to do this outside of cups, with „pure“ Gutenprint?
> 
> Either way, how am I to do this?

You would have to do this outside of CUPS, at least.  CUPS (at least at the time we wrote the CUPS
driver for Gutenprint) doesn't support DeviceN.

Gutenprint provides (for Epson printers, at any rate) the underlying API to do this, but there
hasn't been enough interest to write a decent user tool to do this.  There is a hack in the
testpattern generator (src/testpattern) to do this, but to be honest I wrote this years ago just as
a demo and I don't remember myself how to use it.  What it amounts to is that you need to create a
file header with the required options (which there are examples of) and use the Raw output mode, and
then the data has to be provided in binary at the end of the file.  As I said, I (or somebody) would
have to study this myself to reconstruct how to use it.  The file format is straightforward enough,
8 or 16 byte native endian data in pixel order, but I just don't recall the details.

Re: [Gimp-print-devel] Raw input mode via CUPS?

[Marius S. <ma...@ma...>]

Thanks very much for this explanation - I’m unsure whether I’d be able to study and reconstruct this with reasonable effort and I’m not even sure about the benefit would be worth the effort to me.

Kind regards
Marius Steffen
ma...@ma...



> Am 05.06.2021 um 17:20 schrieb Robert Krawitz <rl...@al...>:
> 
> On 6/4/21 8:21 PM, Marius Steffen wrote:
>> Hi everbody,
>> 
>> I’m currently trying to partially replace Epson’s driver for my SureColor P800 printer. My specific
>> reason is the driver’s inability to print CMYK and directly access all the printers ink channels.
>> While I found out how to do CMYK prints using Gutenprint, I’m failing to do CcMmYKkk prints with
>> files provided in DeviceN space.
>> 
>> I’ve found this rather old message in the mailing list
>> archive: https://sourceforge.net/p/gimp-print/mailman/message/19908513/
>> <https://sourceforge.net/p/gimp-print/mailman/message/19908513/>
>> Essentially, what I’m trying to do is what Robert described in 2) as „raw input with raw color
>> correction“, but I’m failing to see how to do that via CUPS - is this even possible, or is one
>> forced to do this outside of cups, with „pure“ Gutenprint?
>> 
>> Either way, how am I to do this?
> 
> You would have to do this outside of CUPS, at least.  CUPS (at least at the time we wrote the CUPS
> driver for Gutenprint) doesn't support DeviceN.
> 
> Gutenprint provides (for Epson printers, at any rate) the underlying API to do this, but there
> hasn't been enough interest to write a decent user tool to do this.  There is a hack in the
> testpattern generator (src/testpattern) to do this, but to be honest I wrote this years ago just as
> a demo and I don't remember myself how to use it.  What it amounts to is that you need to create a
> file header with the required options (which there are examples of) and use the Raw output mode, and
> then the data has to be provided in binary at the end of the file.  As I said, I (or somebody) would
> have to study this myself to reconstruct how to use it.  The file format is straightforward enough,
> 8 or 16 byte native endian data in pixel order, but I just don't recall the details.