Text is illegible when a PDF has non-embedded CID TrueType and no character map about imgproxy

[DarthSim]

Yeah, it seems so

[DarthSim]

Hey @swishstache!

I guess convert and mutool work correctly because your system has the Trebuchet MS font installed. If you put Trebuchet MS to /usr/share/fonts in the imgproxy's Docker image, imgproxy will render this PDF correctly.

As far as I understand, there's no way to map characters correctly without having a font or a character map.

We provide only a single font in imgproxy's distribution because this is usually enough for most users, and a full font set could weigh more than the whole imgproxy distribution.

[DarthSim]

BTW, I installed ImageMagick inside the imgproxy's Docker container, and it also rendered the PDF incorrectly until I installed Trebuchet MS.

[swishstache]

As far as I understand, there's no way to map characters correctly without having a font or a character map.

That makes sense. I assume substitution (using Dejavu) doesn't occur because the document claims it has a mapping (the "uni" column below) but does not. WDYT?

name                                 type              encoding         emb sub uni object ID
------------------------------------ ----------------- ---------------- --- --- --- ---------
Courier-Bold                         Type 1            WinAnsi          no  no  no       2  0
UniversLTStd45Light,Bold             CID TrueType      Identity-H       no  no  yes      5  0
TrebuchetMS,Bold                     CID TrueType      Identity-H       no  no  yes      9  0
TrebuchetMS                          CID TrueType      Identity-H       no  no  yes     13  0