Convert several-pages TIFF to PDF with layers as pages

Hi
This is my first post here.
My Brother printer can’t send scans as a pdf file, only TIFF to my Linux. I found GIMP 2.10 does a nice job to convert the files and I’d like to know if the default dialogs for import/open tiff and export as pdf (Ctrl+Shift+E) are plugins and where I could read their respective doc to use them in command line to be called by the Brother skey-scantoimage.sh script to automate the conversion.
I read in the procedures and plugins browsers for plug-in-separate-export there is a README file from MM Alastair Robinson & Yoshinori Yamakawa to know which formats are available. I feel from the name of the plugin it could be the ~culprit~ of doing the good job to export layers as separate pages in a single pdf file. Later reading the file-pdf-save2 parameters makes me figure it is the default (better) culprit.
For import I can’t guess which is used, plug-in-separate-proof or plug-in-separate-import or file-tiff-load. The one that triggers on default file-open with GIMP from Nautilus seems fine as it detects multi-pages file and prompts the user what to do.
Please tell me if GIMP command line is the good tool and if I really need to use plugins.
Many thanks

Well, I use kubuntu 20.04 and my old Brother J825 printer / scanner Unfortunately first thing I did was break the sheet-feed, but I can still batch scan using xsane which I assume (might be mistaken) gives similar results to the skey-scantoimage.sh script.

The Gimp procedure plug-in-separate-export is a RGB to CMYK converter (separate+ plugin). Apart from not working in Gimp 2.10, nothing to do with tiff > pdf

If you want to use Gimp to convert your multi-page tiff then you will need a gimp batch command for the conversion and add it to the skey-scantoimage.sh script. That would be along the lines of this GIMP - GIMP Batch Mode

I would consider not using Gimp for this. Gimp makes multi-page PDF’s but because of the low internal compression they are on the large size. Maybe consider using Imagemagick (IM) command line.

mogrify -format pdf -compress jpeg *.tiff

A comparison, I have just scanned it.
2 page A4 text RGB 300 ppi no compression from xsane = 50 MB
Opened and exported in Gimp 7 MB
IM tiff to pdf 2 MB

Only snag with IM is security policies see: pdf - imagemagick - convert not allowed - Ask Ubuntu for the fix.

Bonjour,

Without using Gimp you can compile the latest version of Libtiff LibTIFF - TIFF Library and Utilities — LibTIFF 4.5.0 documentation and use the tiff2pdf utility TIFF2PDF

Perhaps the compilation of the latest version of Libtiff is already done under your Linux OS.

Thank you very much Rich for this kind and efficient advice.

And thank you too SamJ. Happily I have both libtiff5 and libtiff-tools on my system so everything is here to use tiff2pdf :slight_smile: