distinguish and elaborate on downgrading and refrying

1 files changed, 38 insertions, 10 deletions

diff --git a/USE.md b/USE.md
index 1af417b..3e4cb3f 100644
--- a/USE.md
+++ b/USE.md
@@ -1,21 +1,37 @@
 # Print
 
-## Direct print to Brother
+## Garbled text
 
-Use pdf 1.3
+LibreOffice Writer 7.5 exports PDF 1.6 files
+with embedded subset fonts,
+which renders garbled text
+e.g. using "direct print" from a USB dongle
+on a Brother HL-4040CN Laser printer.
+A workaround is to [downgrade](#Downgrade) to PDF 1.2 like this:
 
-Convert pdf:
+	ps2pdf12 infile outfile
 
-	localps2pdf
+## Unsupported PDF data
 
-...or try tab-complete for alternative scripts,
-or look at underlying scripts `pdftops`and `pstopdf13`.
+Some PDF generators,
+e.g. from Deutche Bahn or Microsoft Word on Windows,
+contains some yet unidentified PDF data,
+which is replaced by an error message
+e.g. using "direct print" from a USB dongle
+on a Brother HL-4040CN Laser printer.
+A workaround is to [refry](#Refry) like this:
 
-## Direct print odd format
+	pdf2ps infile - | ps2pdf12 - outfile
+
+or using this custom wrapper, where available:
+
+	localpdf2ps2pdf infile
+
+If the above fails to work,
+then try replace `pdf2ps`
+with either `pdftops` or `pdftocairo`.
+Beware that options may differ.
 
-	pdftocairo -pdf -paper A4 infile outfile
-	pdftops %f
-	ps2pdf13 infile outfile
 
 ## PDF resizing and/or scaling
 
@@ -167,3 +183,15 @@ Source: <https://stackoverflow.com/a/26989410>
 
 [overridden]: <https://stackoverflow.com/a/59608992>
   "stackoverflow answer mentioning importance of Ghostscript argument order"
+
+## Terminology
+
+### Downgrade
+
+To parse a PDF file and recreate a new PDF file using reduced features
+is called [downgrading](https://stackoverflow.com/questions/50868207#comment88765513_50871699).
+
+### Refry
+
+To "flatten" a PDF file to Postscript and then recreate as new PDF file
+is called [refrying](https://www.prepressure.com/pdf/basics/refrying).