EPSON driver：The print-color-mode has no effect

[machencheng2]

Ubuntu 22.04 doing C++ development
cups: 2.4.2
Epson printer driver：「Epson Inkjet Printer Driver (ESC/P-R) for Linux」
（※I also tried 「Epson Inkjet Printer Driver (ESC/P-R2) for Linux」, same result）
Install using the following method.
sudo apt install printer-driver-escpr psutils libcupsimage2 cups

1.The print-color-mode has no effect
First, I added the printer by lpadmin
lpadmin -p epson789 -E -v ipp://10.96.116.36/ipp/print -i '/home/vagrant/Documents/Epson-L8160_Series-epson-escpr-en.ppd'

then，i query supported color options
✘ ٩(;ω;*)و  /usr/lib/cups/filter  ipptool -tv ipp://localhost/printers/epson789 get-printer-attributes.test | grep color
print-color-mode-default (keyword) = color
print-color-mode-supported (1setOf keyword) = monochrome,color

then i append print-color-mode with cupsAddOption, no effect

then，i tried
lp -d epson789 -o print-color-mode=monochrome /home/text_demo.pdf
lp -d epson789 -o print-color-mode=color /home/text_demo.pdf

But print-color-mode doesn't work，I started the system-config-printer

You can see that the Job Option contains print-color-mode, but the change will not work.
Only the Color in the Printer Option works.
I can see Color is Ink option.

so,if I use the following command，
lp -d epson789 -o Ink=MONO /tmp/aaaa.pdf 
It can be printed in the specified color.

But now I'm doing the cups application.
When the supported options are found through print-color-mode and the user specifies the color, I want to set the print-color-mode through cupsAddOption and then print correctly, what should I do now?
Do I have to parse ppd? Even if I parse it, I don't know that the color option is Ink

following is log
I see the parameters have been passed to epson-escpr-wrapper

epson-escpr-wrapper does not pass parameters to the printer

in backen->ipp.c
if (argc == 6)
{
num_files = 0;
files = NULL;
send_options = !_cups_strcasecmp(final_content_type, "application/pdf") ||
!_cups_strcasecmp(final_content_type, "application/vnd.cups-pdf") ||
!_cups_strncasecmp(final_content_type, "image/", 6);

    fputs("DEBUG: Sending stdin for job...\n", stderr);
}

Because it is vnd.cup-raster, no parameters are passed to the printer

What I can do is, when I find out that print-color-mode is monochrome, I can also bring the Ink=MONO option, which can temporarily solve the problem. What's the right way to do it.

[zdohnal]

Hi,

CUPS 2.4.2 is old version which contained this bug. The latest version should have this fixed, if the Epson driver does not use any non-standard PPD keyword for handling color.

[machencheng2]

I tried 2.4.11, but the problem still exists.

[zdohnal]

I'm sorry, I've missed your lpoptions output - then print-color-mode won't work at all, because your driver uses non-standard PPD keyword for color printing. You will have to use its PPD keyword or use a printer application like legacy-printer-app, which does its best to encode non-standard PPD keywords as vendor IPP attributes, and use the IPP attribute created by printer application.