[cups] printing b/w with HP Laserjet M277 Pro MFP

[Helge Blischke]

> Am 04.12.2017 um 10:44 schrieb Matthias Apitz <guru at unixarea.de>:
> 
> El día lunes, febrero 06, 2017 a las 09:56:49a. m. -0500, Michael Sweet escribió:
> 
>> Matthias,
>> 
>> Putting "*ColorDevice: False" in a PPD tells the PDF to PostScript converter to output B&W color data.
>> 
> 
> Michael,
> 
> The PPD in question for my printer 'ps-bw' has the "*ColorDevice: False"
> statement. I was now highly surprised when I printed a test page from
> the CUPS' web frontend, that it comes out as color. I have below the
> relevant started filters from the debug level error_log file. It seems
> to me that PDF to PS conversion is only involved for the (non existing)
> banner page, but not for the test page itself. I'm wrong?
> 
> Thanks
> 
> 	matthias
> 
> 
> 
> 
> $ egrep 'gs |PID |bannertopdf|pdftops|socket' error_log.job445
> D [04/Dec/2017:06:40:43 +0100] [Job 445] bannertopdf (application/vnd.cups-pdf-banner to application/pdf, cost 32)
> D [04/Dec/2017:06:40:43 +0100] [Job 445] pdftops (application/pdf to application/vnd.cups-postscript, cost 66)
> D [04/Dec/2017:06:40:43 +0100] [Job 445] envp[23]="DEVICE_URI=socket://192.168.2.4:9100/?waiteof=false"
> I [04/Dec/2017:06:40:43 +0100] [Job 445] Started filter /usr/local/libexec/cups/filter/bannertopdf (PID 2629)
> I [04/Dec/2017:06:40:43 +0100] [Job 445] Started filter /usr/local/libexec/cups/filter/pdftops (PID 2630)
> I [04/Dec/2017:06:40:43 +0100] [Job 445] Started backend /usr/local/libexec/cups/backend/socket (PID 2631)
> D [04/Dec/2017:06:40:43 +0100] [Job 445] pdftops - copying to temp print file \"/var/spool/cups/tmp/00a465a2c51e9\"
> D [04/Dec/2017:06:40:43 +0100] [Job 445] PID 2629 (/usr/local/libexec/cups/filter/bannertopdf) exited with no errors.
> D [04/Dec/2017:06:40:43 +0100] [Job 445] Running command line for gs: gs -q -dNOPAUSE -dBATCH -dSAFER -dNOMEDIAATTRS -sDEVICE=ps2write -sOUTPUTFILE=%stdout -dLanguageLevel=2 -r300 -dCompressFonts=false -dNoT3CCITT -dNOINTERPOLATE -c \'save pop\' -f /var/spool/cups/tmp/00a465a2c51e9
> D [04/Dec/2017:06:40:43 +0100] [Job 445] Started filter gs (PID 2632)
> D [04/Dec/2017:06:40:43 +0100] [Job 445] Started filter pstops (PID 2633)
> D [04/Dec/2017:06:40:48 +0100] [Job 445] PID 2632 (gs) exited with no errors.
> D [04/Dec/2017:06:40:48 +0100] [Job 445] PID 2633 (pstops) exited with no errors.
> D [04/Dec/2017:06:40:48 +0100] [Job 445] PID 2630 (/usr/local/libexec/cups/filter/pdftops) exited with no errors.
> D [04/Dec/2017:06:40:48 +0100] [Job 445] PID 2631 (/usr/local/libexec/cups/backend/socket) exited with no errors.
> $
> 
> 

The 
*ColorDevice:
PPD keyword needs to be interpreted by one of the filters in the chain.
I’d suggest to file a bug at openprinting for the cups-filters project (especially the pdftops filter.
When this filter uses Ghostscript, it is quite easy to take car of this.

Helge