Re: [SOLVED] Re: Creating PDF/A from LaTeX source and from existing PDF

[Max Nikulin]

On 10/07/2024 15:37, Ceppo wrote:

but I couldn't build a working gs command.

[...]

[1]: https://github.com/qpdf/qpdf/issues/85


There is a link to gs arguments

[SOLVED] Re: Creating PDF/A from LaTeX source and from existing PDF

[Ceppo]

On Mon, Jul 08, 2024 at 05:20:57PM GMT, Jeffrey Walton wrote:
> The pdf-linter I use to verify a pdf document is qpdf,
> . It is available on most distributions,
> including Debian, Fedora and Red Hat.
>
> The command to check the document is `qpdf --check `.

This command doesn't show me any info abouy PDF/A compliance. man says it
"merely checks that the PDF file is syntactically valid".

> > I will also probably have to upload under the same requirement some
> > third-party PDF, which is not PDF/A, without access to an editable version.
> > Is there a way to convert them to PDF/A? I know that converting from an
> > editable version would be the correct way for this, but I have no real way
> > to get it.
>
> qpdf may provide this functionality, but I have never used it.

[1] says PDF/A conversion is out of scope for the library. However, [2] pointed
me to ocrmypdf and this command produces a valid PDF/A-1b file:

ocrmypdf --output-type pdfa-1 --tesseract-timeout=0 --skip-text \
input.pdf output.pdf

Another comment pointed out this relies on ghostscript, but I couldn't build a
working gs command. I will try harder as soon as I have some free time. Anyway
I have my conversion tool now, and I'm happy with it.

As a short summary of this thread outcome, I can:

- compile with `pdflatex` as usual
- convert to PDF/A with the `ocrmypdf` command above (probably not the most
  clean way, but it works)
- validate with veraPDF

Thanks everyone for your help, it was higly appreciated even when it didn't
work as expected!


[1]: https://github.com/qpdf/qpdf/issues/85
[2]: https://github.com/qpdf/qpdf/issues/85#issuecomment-1278055568


--
Ceppo


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Re: Creating PDF/A from LaTeX source and from existing PDF

[Jeffrey Walton]

On Mon, Jul 8, 2024 at 5:56 PM Ceppo  wrote:
>
> On Wed, Jul 03, 2024 at 06:38:51PM GMT, Richard wrote:
> > From LaTeX, this is quite simple, there's a package for that - as for pretty
> > much everything in the LaTeX world. Googling for just like 10 sec could have
> > given you this great guide: https://webpages.tuni.fi/latex/pdfa-guide.pdf
>
> I did my research and found the document you linked. In fact it's what pointed
> me to the pdfx LaTeX package, but I couldn't make it work. I acknowledge I
> missed its reference to veraPDF, though.
>
> > gs -dQUIET -dUseCIEColor -sProcessColorModel=DeviceCMYK -sDEVICE=pdfwrite
> > -dPDFACompatibilityPolicy=1 -dCompressFonts=true -dSubsetFonts=true
> > -sFONTPATH=/usr/share/fonts/ -o  
>
> The output isn't accepted by veraPDF, either. I will try to understand
> something more about ghostscript.

Have a look at <https://stackoverflow.com/q/1659147>. It discusses
some of the finer points of PDF/A conversion in the comments, like
color spaces.

Jeff

Re: Creating PDF/A from LaTeX source and from existing PDF

[Jeffrey Walton]

On Wed, Jul 3, 2024 at 12:13 PM Ceppo  wrote:
>
> I wrote a report with LaTeX, and afterwards discovered it must be
> PDF/A-compliant - which wasn't. I found the pdfx LaTeX package and followed 
> its
> instructions, thus obtaining a file that should be PDF/A and pdfinfo 
> identifies
> as such, but my employer's upload form thinks isn't. Is pdfinfo reliable 
> enough
> that I can tell my employer his form is broken? If not, how can I make sure
> that pdflatex's output is actually PDF/A-compliant?

The pdf-linter I use to verify a pdf document is qpdf,
<https://github.com/qpdf/qpdf>. It is available on most distributions,
including Debian, Fedora and Red Hat.

The command to check the document is `qpdf --check `.

> I will also probably have to upload under the same requirement some 
> third-party
> PDF, which is not PDF/A, without access to an editable version. Is there a way
> to convert them to PDF/A? I know that converting from an editable version 
> would
> be the correct way for this, but I have no real way to get it.

qpdf may provide this functionality, but I have never used it. From
the project's description: "qpdf is a command-line tool and C++
library that performs content-preserving transformations on PDF files.
It supports linearization, encryption, and numerous other features. It
can also be used for splitting and merging files, creating PDF files
(but you have to supply all the content yourself), and inspecting
files for study or analysis."

Another tool I would look at is GhostScript. It looks like it can
convert to PDF/A: <https://stackoverflow.com/a/9343820>.

> A requirement of any solution is that it doesn't rely on non-DFSG-compliant
> software, including online conversion tools.

Jeff

Re: Creating PDF/A from LaTeX source and from existing PDF

[Ceppo]

On Wed, Jul 03, 2024 at 11:15:51AM GMT, Henning Follmann wrote:
> On Wed, Jul 03, 2024 at 01:06:56PM +, Ceppo wrote:
> > A requirement of any solution is that it doesn't rely on non-DFSG-compliant
> > software, including online conversion tools.
>
> Please looks at this thread at StackExchange. I found that to be very
> helpful.
> https://tex.stackexchange.com/questions/130201/pdf-a-with-hyperref-on-tex-live-2013/136653#136653
>
> Please let me know how it works out for you.

Hello.
Thanks for pointing to the thread, but the solution isn't suitable for me. I
need a solution that does not rely on non-DFSG-compliant software, but the
first step requires to use a file from a zip archive [1] with a license that
explicitly forbids to modify and sell it.


[1]: http://www.eci.org/_media/downloads/icc_profiles_from_eci/ecirgbv20.zip


--
Ceppo


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Re: Creating PDF/A from LaTeX source and from existing PDF

[Ceppo]

On Wed, Jul 03, 2024 at 03:36:17PM GMT, to...@tuxteam.de wrote:
> On Wed, Jul 03, 2024 at 01:06:56PM +, Ceppo wrote:
> > I wrote a report with LaTeX, and afterwards discovered it must be
> > PDF/A-compliant - which wasn't. I found the pdfx LaTeX package and followed
> > its instructions, thus obtaining a file that should be PDF/A and pdfinfo
> > identifies as such, but my employer's upload form thinks isn't [...]
>
> Uh-oh. We set the standards, but won't tell you what they are.

Well, in fact they did tell - they just did *after* I produced my report. But
yes, the workflow is very broken...

> Not concrete help, but the Wikipedia [1] makes for an interesting
> read (including refs to bunches of test suites you can throw at your
> publisher's site to find out where their validator is failing).

I read about Isartor Test Suite, but [1] says it checks if the validator
accepts non-compliant files, not if it rejects compliant files.

> And there seems to be a kind of semi-official validaror, according
> to the above ref.

I guess you mean veraPDF?


[1]: https://pdfa.org/resource/isartor-test-suite/


--
Ceppo


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Re: Creating PDF/A from LaTeX source and from existing PDF

[Ceppo]

On Wed, Jul 03, 2024 at 06:38:51PM GMT, Richard wrote:
> From LaTeX, this is quite simple, there's a package for that - as for pretty
> much everything in the LaTeX world. Googling for just like 10 sec could have
> given you this great guide: https://webpages.tuni.fi/latex/pdfa-guide.pdf

I did my research and found the document you linked. In fact it's what pointed
me to the pdfx LaTeX package, but I couldn't make it work. I acknowledge I
missed its reference to veraPDF, though.

> gs -dQUIET -dUseCIEColor -sProcessColorModel=DeviceCMYK -sDEVICE=pdfwrite
> -dPDFACompatibilityPolicy=1 -dCompressFonts=true -dSubsetFonts=true
> -sFONTPATH=/usr/share/fonts/ -o  

The output isn't accepted by veraPDF, either. I will try to understand
something more about ghostscript.


--
Ceppo


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Re: Creating PDF/A from LaTeX source and from existing PDF

[Ceppo]

On Wed, Jul 03, 2024 at 10:52:06PM GMT, y...@vienna.at wrote:
> Well, that is my way:

Thanks for providing your script. I tried it with one tweak:

> latex  .../Nix.tex  .../Nix.dvi
> dvips -o Nix.ps  Nix.pdf
   ^^^
I guess here you meant Nix.dvi...

> ps2pdf ... Nix.ps ... Nix.pdf
> chmod 755 script
> All works since many many years absolutly perfect, nothing else ever was is
> needed

However, the resulting PDF is not recognized as PDF/A by veraPDF. Have you
tested it with something else?


--
Ceppo


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Re: Creating PDF/A from LaTeX source and from existing PDF

[Ceppo]

On Wed, Jul 03, 2024 at 10:18:01AM GMT, Sarunas Burdulis wrote:
> pdfinfo probably only reads metadata, but does not do any PDF/A compliance
> validation.
>
> VeraPDF seems to work for validation (https://verapdf.org/software/).

I don't know about pdfinfo, but it looks like veraPDF at least agrees with my
contractor's form. Thanks for pointing me to it, it looks like now I have a
tool to check if my document is compliant.


--
Ceppo


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Re: Creating PDF/A from LaTeX source and from existing PDF

[Richard]

The first bit is just a warning, not an error. Of course, you could check
what has changed in v9.11 that makes this not recommended anymore. Maybe
they already handle it internally when you set -dPDFACompatibilityPolicy=1
and the old setting can interfere. But when the output of the validator
doesn't change, it's probably just meant as you don't need to specify this
anymore, we activate it ourselves.

Speaking of the validator, those look more like warnings too and not like
deal breakers. In the end, only you know what your contractor expects of
you. And if they don't even bother inspecting the result, this will be
irrelevant. After all, the only reason PDF/A exists is for archiving
reasons. It pretty much just throws out all the proprietary clutter from
the PDF standard. The important thing is that fonts are embedded to always
be able to display them correctly, and that it's specified how images and
other media are embedded. If your contractor expects more of you, they
should pay for the appropriate software.

Richard

PS: this isn't really meant for this, but you could install Scribus and try
to import the PDF there. It also has a validator similar to Adobes
Preflight. Maybe it can give you a more precise result. I'm not sure if it
even can output PDF/A, I only know that it does PDF/X, but maybe it can
even be used for better conversion to PDF/A. The last time I tried to
import a large PDF into Scribus it got kinda stuck, but it has evolved
since then and maybe it was a hardware limitation.

On Thu, Jul 4, 2024 at 4:38 AM Greg Marks  wrote:

> $gs -dQUIET -dUseCIEColor -sProcessColorModel=DeviceCMYK -sDEVICE=pdfwrite 
> -dPDFACompatibilityPolicy=1
> -dCompressFonts=true -dSubsetFonts=true -sFONTPATH=/usr/share/fonts/ -o
> new.pdf old.pdf
>
> [Gives warnings:
>
>GPL Ghostscript 10.00.0:
>
>Use of -dUseCIEColor detected!
>Since the release of version 9.11 of Ghostscript we recommend you do
> not set
>-dUseCIEColor with the pdfwrite/ps2write device family.]
>
> Uploading new.pdf to https://www.pdfforge.org/online/en/validate-pdfa
> produces report "The file is not a valid PDF/A document" with these
> details:
>
>ISO 19005-1:2005
>6.1.8
>The object number and generation number shall be separated
>by a single white-space character. The generation number
>and obj keyword shall be separated by a single white-space
>character. The object number and endobj keyword shall each be
>preceded by an EOL marker. The obj and endobj keywords shall
>each be followed by an EOL marker.
>
>ISO 19005-1:2005
>6.1.7
>The stream keyword shall be followed either by a CARRIAGE RETURN
>(0Dh) and LINE FEED (0Ah) character sequence or by a single
>LINE FEED character. The endstream keyword shall be preceded
>by an EOL marker
>
> Repeating with the flag -dUseCIEColor removed prevents the Ghostscript
> warnings but doesn't change the PDF/A validation result.
>
> Best regards,
> Greg Marks
>

Re: Creating PDF/A from LaTeX source and from existing PDF

[jeremy ardley]

On 4/7/24 11:10, Stefan Monnier wrote:

This might qualify as a bug in your MUA (it can make sense to require
a small font for some parts of the message, but it seems this style
applies to the whole message, which makes no sense), tho maybe it's due
to some particularity of your configuration, or of the way you use your
MUA's editor.



I use thunderbird and I usually remember to select Sending Format as 
text only when sending to lists. This should  always render correctly on 
any mua

Re: Creating PDF/A from LaTeX source and from existing PDF

[Stefan Monnier]

Hi Richard,

I don't see any problem because I'm reading this mailing-list from a MUA
that's mostly text-only and doesn't try to use variable-size fonts, but
looking at the HTML you send I see:

>  style="font-family:arial,helvetica,sans-serif;font-size:small">

repeated several times.  I have no idea why your MUA puts it there, but
I suspect that's the reason some of the readers here find your email's
messages to be hard to read: your mail specifically asks for
`font-size:small`.

This might qualify as a bug in your MUA (it can make sense to require
a small font for some parts of the message, but it seems this style
applies to the whole message, which makes no sense), tho maybe it's due
to some particularity of your configuration, or of the way you use your
MUA's editor.


Stefan

small font (was: Re: Creating PDF/A from LaTeX source and from existing PDF)

[Max Nikulin]

I am in doubts what is more rude:

On 04/07/2024 04:02, Richard wrote:

Please stop using such a dinky font. There are plenty of old farts
trying to read this list.


- writing this before an attempt to hijack the thread using an already 
discussed question,


Tell that to your mail program. If it chooses to show you the mail that 
way, don't blame me.


- insisting on an "industry standard" mail style


Tell that to your mail progra=


---^^^

Re: Creating PDF/A from LaTeX source and from existing PDF

[Max Nikulin]

On 04/07/2024 04:49, Greg Marks wrote:


$gs -dQUIET -dUseCIEColor -sProcessColorModel=DeviceCMYK -sDEVICE=pdfwrite 
-dPDFACompatibilityPolicy=1 -dCompressFonts=true -dSubsetFonts=true 
-sFONTPATH=/usr/share/fonts/ -o new.pdf old.pdf

[...]

The object number and generation number shall be separated
by a single white-space character. The generation number

[...]

The stream keyword shall be followed either by a CARRIAGE RETURN


I expect that pdftk and qpdf have their own serializers. I have no idea 
if they can transform a file to a PDF/A compliant document, but they 
might use proper separators.


Perhaps LaTeX documents require some tuning (metadata blocks, etc.). If 
you use pdflatex then I would try lualatex.

Re: Creating PDF/A from LaTeX source and from existing PDF

[Greg Marks]

> Now, for just random PDFs, this is a bit more tricky, but you can do so
> with ghostscript. Now, this sadly doesn't have such a great guide, but
> something like this should do the trick, though that's only PDF/A-1 for all
> I can tell. If your contractor needs a different version, you'll have to
> adapt it:
> 
> gs -dQUIET -dUseCIEColor -sProcessColorModel=DeviceCMYK -sDEVICE=pdfwrite
> -dPDFACompatibilityPolicy=1 -dCompressFonts=true -dSubsetFonts=true
> -sFONTPATH=/usr/share/fonts/ -o  

This does not seem to work.  For example:

$cd /tmp

$wget -O old.pdf https://arxiv.org/pdf/2406.18499

$gs -dQUIET -dUseCIEColor -sProcessColorModel=DeviceCMYK -sDEVICE=pdfwrite 
-dPDFACompatibilityPolicy=1 -dCompressFonts=true -dSubsetFonts=true 
-sFONTPATH=/usr/share/fonts/ -o new.pdf old.pdf

[Gives warnings: 

   GPL Ghostscript 10.00.0:

   Use of -dUseCIEColor detected!
   Since the release of version 9.11 of Ghostscript we recommend you do not set
   -dUseCIEColor with the pdfwrite/ps2write device family.]

Uploading new.pdf to https://www.pdfforge.org/online/en/validate-pdfa
produces report "The file is not a valid PDF/A document" with these
details:

   ISO 19005-1:2005
   6.1.8
   The object number and generation number shall be separated
   by a single white-space character. The generation number
   and obj keyword shall be separated by a single white-space
   character. The object number and endobj keyword shall each be
   preceded by an EOL marker. The obj and endobj keywords shall
   each be followed by an EOL marker.

   ISO 19005-1:2005
   6.1.7
   The stream keyword shall be followed either by a CARRIAGE RETURN
   (0Dh) and LINE FEED (0Ah) character sequence or by a single
   LINE FEED character. The endstream keyword shall be preceded
   by an EOL marker

Repeating with the flag -dUseCIEColor removed prevents the Ghostscript
warnings but doesn't change the PDF/A validation result.

Best regards,
Greg Marks


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Re: Creating PDF/A from LaTeX source and from existing PDF

[Richard]

Well, guess what, I haven't done anything to change the way messages look.
The only settings I ever change is how they are displayed to me. And never
has anyone ever had an issue with that, in many years. Probably because
other people are just not using unusable software. And quite frankly,
punishing the ignorant for their ignorance is the best policy there is. If
you go out of your way to make life as difficult as possible for yourself,
that's your issue. Don't make it everybody else's issue. Quit whining and
learn how to search the internet for solutions first. The chance that
you're the first to ask such basic questions is pretty much not existent.
And if you refuse to learn, that's up to you. But then you didn't learn
live's biggest lesson, you never stop learning.

And with that I'm ending this ridiculous discussions, this has gone far
enough off-topic.

Best

On Wed, Jul 3, 2024 at 11:12 PM Greg Wooledge  wrote:

> That said, I wonder *why* you would go out of your way to make your
> messages harder to read for people who don't know how to activate every
> single feature of their MUA.
>

Re: Creating PDF/A from LaTeX source and from existing PDF

[Greg Wooledge]

On Wed, Jul 03, 2024 at 23:02:16 +0200, Richard wrote:
> >
> > Please stop using such a dinky font. There are plenty of old farts trying
> > to read this list.
> 
> Tell that to your mail program. If it chooses to show you the mail that
> way, don't blame me. Everything needed to display it any way you want is
> there, it just needs to be used. Thunderbird can define a minimum text size
> and refuse messages to use their own font. If your archaic software doesn't
> do basics, blame the dev - or better yet yourself, as the choice is yours.

I never saw any problem, as my terminal-based MUA renders your text/plain
part just fine.  I didn't even know you were posting multi-part messages
until someone complained about the font size.

That said, I wonder *why* you would go out of your way to make your
messages harder to read for people who don't know how to activate every
single feature of their MUA.  It would be a good policy to make your
messages as easy to read as possible, for as many people as possible,
by default.

If you're simply punishing the ignorant for their ignorance, well, that
seems a bit spiteful.

Re: Creating PDF/A from LaTeX source and from existing PDF

[Richard]

>
> Please stop using such a dinky font. There are plenty of old farts trying
> to read this list.

Tell that to your mail program. If it chooses to show you the mail that
way, don't blame me. Everything needed to display it any way you want is
there, it just needs to be used. Thunderbird can define a minimum text size
and refuse messages to use their own font. If your archaic software doesn't
do basics, blame the dev - or better yet yourself, as the choice is yours.

And the other part is its own thread. I've commented everything I know.
Just redo your book as native ePub, there's no way around it. If you want
to find shortcuts, you'll have to do your own research, even beyond Linux
there probably is no piece of software that can do what you are looking
for. But on the other hand, I'd never have expected ghostscript - or to be
more precise GhostPDL, if I'm not mistaken - to be able to handle
Microsoft's rubbish XPS format and convert that to a proper PDF. So who
knows? Instead of going on other people's nerves with an unsolvable issue,
put those questions into the search machine of your choice. Maybe it will
be more competent than your mail program.

Richard

Am Mi., 3. Juli 2024 um 21:20 Uhr schrieb Van Snyder <
van.sny...@sbcglobal.net>:

> On Wed, 2024-07-03 at 18:38 +0200, Richard wrote:
>
> For anything further, you'll have to research yourself as ghostscript is
> very complex but used by many people.
>
>
> Please stop using such a dinky font. There are plenty of old farts trying
> to read this list.
>
>
> Can ghostscript convert a PDF generated by pdflatex to ePub or mobi?
>
> Calibre made a mess, especially of tables. E-mailing it to my Kindle
> account with "convert" in the subject line made a mess. Tools to convert
> LaTeX to html in the hope of ultimately getting to ePub or mobi utterly
> failed, so I don't know whether they in the end would have made a mess.
>
>

Re: Creating PDF/A from LaTeX source and from existing PDF

[Van Snyder]

On Wed, 2024-07-03 at 15:31 -0400, e...@gmx.us wrote:
> On 7/3/24 15:20, Van Snyder wrote:
> > On Wed, 2024-07-03 at 18:38 +0200, Richard wrote:
> > > For anything further, you'll have to research yourself as
> > > ghostscript
> > > is very complex but used by many people.
> > 
> > Please stop using such a dinky font.
> 
> That's what ctrl-shift-+ is for.

Yeah, those of us who have been at this for a decade or two know that.
But it makes everything else so large that it doesn't fit anymore, even
at full screen, on my laptop.

Re: Creating PDF/A from LaTeX source and from existing PDF

[eben]

On 7/3/24 15:20, Van Snyder wrote:

On Wed, 2024-07-03 at 18:38 +0200, Richard wrote:

For anything further, you'll have to research yourself as ghostscript
is very complex but used by many people.


Please stop using such a dinky font.


That's what ctrl-shift-+ is for.

Re: Creating PDF/A from LaTeX source and from existing PDF

[Van Snyder]

On Wed, 2024-07-03 at 18:38 +0200, Richard wrote:
> For anything further, you'll have to research yourself as ghostscript
> is very complex but used by many people.

Please stop using such a dinky font. There are plenty of old farts
trying to read this list.


Can ghostscript convert a PDF generated by pdflatex to ePub or mobi?

Calibre made a mess, especially of tables. E-mailing it to my Kindle
account with "convert" in the subject line made a mess. Tools to
convert LaTeX to html in the hope of ultimately getting to ePub or mobi
utterly failed, so I don't know whether they in the end would have made
a mess.

Re: Creating PDF/A from LaTeX source and from existing PDF

[Richard]

>From LaTeX, this is quite simple, there's a package for that - as for
pretty much everything in the LaTeX world. Googling for just like 10 sec
could have given you this great guide:
https://webpages.tuni.fi/latex/pdfa-guide.pdf

Now, for just random PDFs, this is a bit more tricky, but you can do so
with ghostscript. Now, this sadly doesn't have such a great guide, but
something like this should do the trick, though that's only PDF/A-1 for all
I can tell. If your contractor needs a different version, you'll have to
adapt it:

gs -dQUIET -dUseCIEColor -sProcessColorModel=DeviceCMYK -sDEVICE=pdfwrite
-dPDFACompatibilityPolicy=1 -dCompressFonts=true -dSubsetFonts=true
-sFONTPATH=/usr/share/fonts/ -o  

Now, one common thing that can happen is that you don't have the necessary
fonts installed (I'm using the system-wide fonts path here, but you can
also set any other path) so the result would look off. In that case, you
could just convert the fonts into outlines, which will make text
machine-unreadable and the file much bigger. For that,
replavce "-dCompressFonts=true -dSubsetFonts=true
-sFONTPATH=/usr/share/fonts/" with "-dNoOutputFonts". Since I'm not
completely certain about ghostscripts defaults, you can also add
"-dDownsampleMonoImages=false -dDownsampleGrayImages=false
-dDownsampleColorImages=false" to make sure the images stay otherwise
unchanged.

For anything further, you'll have to research yourself as ghostscript is
very complex but used by many people.

Best
Richard

Re: Creating PDF/A from LaTeX source and from existing PDF

[tomas]

On Wed, Jul 03, 2024 at 11:05:59AM -0400, Henning Follmann wrote:
> On Wed, Jul 03, 2024 at 03:36:17PM +0200, to...@tuxteam.de wrote:

[...]

> > Uh-oh. We set the standards, but won't tell you what they are.
> 
> But they did! They say PDF/A. But you have a point that this maybe is
> not enough. Which version of PDF/A are we talking about?

Don't get me wrong. The idea of PDF/A is great, the idea of using it
is too... but judging by the Wikipedia entry, the actual implementation
seems to be a mess, with several "levels", one semi-official validator
and a whole bunch of pairwise incompatible validators.

So just specifying PDF/A sounds like a sadistic torture coming out of
Catbert's Evil Human Resources Department :-)

Cheers
-- 
t


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Re: Creating PDF/A from LaTeX source and from existing PDF

[Henning Follmann]

On Wed, Jul 03, 2024 at 01:06:56PM +, Ceppo wrote:
> I wrote a report with LaTeX, and afterwards discovered it must be
> PDF/A-compliant - which wasn't. I found the pdfx LaTeX package and followed 
> its
> instructions, thus obtaining a file that should be PDF/A and pdfinfo 
> identifies
> as such, but my employer's upload form thinks isn't. Is pdfinfo reliable 
> enough
> that I can tell my employer his form is broken? If not, how can I make sure
> that pdflatex's output is actually PDF/A-compliant?
> 
> I will also probably have to upload under the same requirement some 
> third-party
> PDF, which is not PDF/A, without access to an editable version. Is there a way
> to convert them to PDF/A? I know that converting from an editable version 
> would
> be the correct way for this, but I have no real way to get it.
> 
> A requirement of any solution is that it doesn't rely on non-DFSG-compliant
> software, including online conversion tools.
> 
> Thanks for any help.
> 

I did research a bit. It is possible to create a PDF/A compliant
document from LaTeX. It looks like you have to do some work though.

Please looks at this thread at StackExchange. I found that to be very
helpful.
https://tex.stackexchange.com/questions/130201/pdf-a-with-hyperref-on-tex-live-2013/136653#136653

Please let me know how it works out for you.

-H


-- 
Henning Follmann   | hfollm...@itcfollmann.com

Re: Creating PDF/A from LaTeX source and from existing PDF

[Henning Follmann]

On Wed, Jul 03, 2024 at 03:36:17PM +0200, to...@tuxteam.de wrote:
> On Wed, Jul 03, 2024 at 01:06:56PM +, Ceppo wrote:
> > I wrote a report with LaTeX, and afterwards discovered it must be
> > PDF/A-compliant - which wasn't. I found the pdfx LaTeX package and followed 
> > its
> > instructions, thus obtaining a file that should be PDF/A and pdfinfo 
> > identifies
> > as such, but my employer's upload form thinks isn't [...]
> 
> Uh-oh. We set the standards, but won't tell you what they are.

But they did! They say PDF/A. But you have a point that this maybe is
not enough. Which version of PDF/A are we talking about?

In general the policy is most likely a good one, because PDF/A gives you
certain guarantees (e.g. That the document renders consistently to the
same printed output, even years after archiving).

> 
> > Thanks for any help.
> 
> Not concrete help, but the Wikipedia [1] makes for an interesting
> read (including refs to bunches of test suites you can throw at your
> publisher's site to find out where their validator is failing).
> 
> And there seems to be a kind of semi-official validaror, according
> to the above ref.

I never tried to generate PDF/A from LaTeX but I am sure it is possible.
By default it would not include any javascript and IIRC it embeds the
font.

> 
> Cheers
> 
> [1] https://en.wikipedia.org/wiki/PDF/A
> -- 
> t



-- 
Henning Follmann   | hfollm...@itcfollmann.com

Re: Creating PDF/A from LaTeX source and from existing PDF

[Sarunas Burdulis]

On 7/3/24 09:06, Ceppo wrote:

I wrote a report with LaTeX, and afterwards discovered it must be
PDF/A-compliant - which wasn't. I found the pdfx LaTeX package and followed its
instructions, thus obtaining a file that should be PDF/A and pdfinfo identifies
as such, but my employer's upload form thinks isn't. Is pdfinfo reliable enough
that I can tell my employer his form is broken? If not, how can I make sure
that pdflatex's output is actually PDF/A-compliant?


pdfinfo probably only reads metadata, but does not do any PDF/A 
compliance validation.


VeraPDF seems to work for validation (https://verapdf.org/software/).

--
Sarunas Burdulis
Dartmouth Mathematics
math.dartmouth.edu/~sarunas

· https://useplaintext.email ·



OpenPGP_signature.asc
Description: OpenPGP digital signature

Re: Creating PDF/A from LaTeX source and from existing PDF

[tomas]

On Wed, Jul 03, 2024 at 01:06:56PM +, Ceppo wrote:
> I wrote a report with LaTeX, and afterwards discovered it must be
> PDF/A-compliant - which wasn't. I found the pdfx LaTeX package and followed 
> its
> instructions, thus obtaining a file that should be PDF/A and pdfinfo 
> identifies
> as such, but my employer's upload form thinks isn't [...]

Uh-oh. We set the standards, but won't tell you what they are.

> Thanks for any help.

Not concrete help, but the Wikipedia [1] makes for an interesting
read (including refs to bunches of test suites you can throw at your
publisher's site to find out where their validator is failing).

And there seems to be a kind of semi-official validaror, according
to the above ref.

Cheers

[1] https://en.wikipedia.org/wiki/PDF/A
-- 
t


signature.asc
Description: PGP signature

Creating PDF/A from LaTeX source and from existing PDF

[Ceppo]

I wrote a report with LaTeX, and afterwards discovered it must be
PDF/A-compliant - which wasn't. I found the pdfx LaTeX package and followed its
instructions, thus obtaining a file that should be PDF/A and pdfinfo identifies
as such, but my employer's upload form thinks isn't. Is pdfinfo reliable enough
that I can tell my employer his form is broken? If not, how can I make sure
that pdflatex's output is actually PDF/A-compliant?

I will also probably have to upload under the same requirement some third-party
PDF, which is not PDF/A, without access to an editable version. Is there a way
to convert them to PDF/A? I know that converting from an editable version would
be the correct way for this, but I have no real way to get it.

A requirement of any solution is that it doesn't rely on non-DFSG-compliant
software, including online conversion tools.

Thanks for any help.


--
Ceppo


signature.asc
Description: PGP signature

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[Richard]

If that isn't a start, I don't know what is. The JSON file can potentially
give an idea about what the other files do.

Am Fr., 28. Juni 2024 um 03:33 Uhr schrieb Van Snyder <
van.sny...@sbcglobal.net>:

> *.kfx, *.yjr and *.yjf are all "data". *.mf is "JSON".
>

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[Richard]

Actually, magika does tell you quite well what you need to know. .yjf could
be something comparable to a JPEG, .kfx seems to be very similar to a BMP
image. .meta seems to be just a JSON text file. .mf could be too, but at
least it will be a text file. The rest is unknown binary data you'll
probably have no way of handling, they will be proprietary. But of course
you can still try the magic bit variant, maybe that can tell you if someone
was already able to write something to handle it.

Am Fr., 28. Juni 2024 um 01:18 Uhr schrieb Van Snyder <
van.sny...@sbcglobal.net>:

> Thanks to Richard for the suggestion to try magika:
>
> # find ./ -type f -exec ~/.local/bin/magika {} \;
> Whence-Energy-2_YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23.sdr/Whence-Energy-2_YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23bbd37f35b4b251f45c1bf42879a62d70.yjf:
> Unknown binary data (unknown) [Low-confidence model best-guess: JPEG image
> data (image), score=28]
> Whence-Energy-2_YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23.sdr/data/.pagination.cache/887fcb7c:
> Unknown binary data (unknown) [Low-confidence model best-guess: PE
> executable (executable), score=71]
> Whence-Energy-2_YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23.sdr/YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23.mf:
> Generic text document (text) [Low-confidence model best-guess: JSON
> document (code), score=59]
> Whence-Energy-2_YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23.sdr/Whence-Energy-2_YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23bbd37f35b4b251f45c1bf42879a62d70.yjr:
> Unknown binary data (unknown) [Low-confidence model best-guess: Intel 80386
> COFF (executable), score=76]
> Whence-Energy-2_YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23.sdr/AssetDownloadMetadata.meta:
> JSON document (code)
> Whence-Energy-2_YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23.kfx: Unknown binary data
> (unknown) [Low-confidence model best-guess: BMP image data (image),
> score=89]
>
> So except for one file, it's still a mystery what e-mailing a PDF to a
> Kindle reader with "convert" (without quotes) in the subject actually
> produces. The Kindle reader can read it, but so far nothing else I've tried
> can. In the end, I want to edit it and re-publish it on Amazon.
>
>

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[Max Nikulin]

On 28/06/2024 01:38, Van Snyder wrote:
So, back to trying to find a competent PDF -to- ePub or PDF -to- mobi 
converter (I haven't yet tried texmate to create a mobi or ePub from the 
LaTeX).


If you seek a solution that allows to get result in a single click then 
the following would not help.


I would not spent time trying to find a PDF to ePub converter. Almost 
certainly PDF generated by LaTeX is not friendly to them (yet?), it is 
for printing.


ePub is a bit special zip archive containing XHTML files that is why, I 
think, it is better to concentrate on LaTeX to HTML converters. Be ready 
to simplify macros used in your TeX files to make them compatible with a 
specific converter. I have never tried TeX4ht, but it may be a better 
option than rather old latex2html. Start from a simple document to 
identify what TeX macros causes issues with your book.


Almost certainly some tuning is required: styles, math representation. I 
have no idea, what is better for ePub: SVG or raster images, MathML. 
There is a number of converters to MathML with their specific shortcomings.


I expect that the following site actively uses TeX as original format:
https://dlmf.nist.gov/ NIST Digital Library of Mathematical Functions

If you do not use advanced LaTeX markup then it may be possible to 
convert it to Org mode https://orgmode.org/ with reasonable efforts. It 
may be converted to HTML using other tools. However some scripting 
(Emacs lisp or lua for pandoc) may be required to achieve decent quality 
of exported documents.


There are should be some blog posts describing troubles and workarounds.

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[Van Snyder]

On Thu, 2024-06-27 at 22:22 +0200, Richard wrote:
> I didn't miss that. "file" will always tell you something, I doubt
> there can be any situation where it will just give you an empty
> output. You because it can get specific, it will tell you if
> something is a text file or binary format it whatever. So what's the
> output?

*.kfx, *.yjr and *.yjf are all "data". *.mf is "JSON".

> 
> On Thu, Jun 27, 2024, 19:33  wrote:
> > On 6/27/24 04:02, Richard wrote:
> > > Am Do., 27. Juni 2024 um 06:33 Uhr schrieb Van Snyder <
> > > van.sny...@sbcglobal.net>:
> > >
> > >> "file" has no idea what
> > >> any of the files are.
> > 
> >  > Otherwise, what exactly does "file" or better "file -i" say?
> > 
> > I think you missed that.
> > 

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[Richard]

I didn't miss that. "file" will always tell you something, I doubt there
can be any situation where it will just give you an empty output. You
because it can get specific, it will tell you if something is a text file
or binary format it whatever. So what's the output?

On Thu, Jun 27, 2024, 19:33  wrote:

> On 6/27/24 04:02, Richard wrote:
> > Am Do., 27. Juni 2024 um 06:33 Uhr schrieb Van Snyder <
> > van.sny...@sbcglobal.net>:
> >
> >> "file" has no idea what
> >> any of the files are.
>
>  > Otherwise, what exactly does "file" or better "file -i" say?
>
> I think you missed that.
>
>

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[Van Snyder]

On Thu, 2024-06-27 at 10:02 +0200, Richard wrote:
> You could try if Googles ML model "magika" can do a better job
> (available via pypi). Otherwise, what exactly does "file" or better
> "file -i" say? Worst case, you could open the files in a hex editor
> and google the first few bits. Chances are the format uses "magic
> bits", so the first few bits in hex are identical for all files of
> that format.
> 
> Am Do., 27. Juni 2024 um 06:33 Uhr schrieb Van Snyder
> :
> > I downloaded everything with the same base name as I sent -- a file
> > and a directory. LibreOffice can't read any of it. Calibre can't
> > read any of it, either in the download or in the mounted Kindle.
> > "file" has no idea what any of the files are.
> > 
> > 
> > 

Thanks to Richard for the suggestion to try magika:

# find ./ -type f -exec ~/.local/bin/magika {} \;
Whence-Energy-2_YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23.sdr/Whence-Energy-
2_YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23bbd37f35b4b251f45c1bf42879a62d70.yjf:
Unknown binary data (unknown) [Low-confidence model best-guess: JPEG
image data (image), score=28]
Whence-Energy-
2_YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23.sdr/data/.pagination.cache/887fcb7c:
Unknown binary data (unknown) [Low-confidence model best-guess: PE
executable (executable), score=71]
Whence-Energy-
2_YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23.sdr/YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23
.mf: Generic text document (text) [Low-confidence model best-guess:
JSON document (code), score=59]
Whence-Energy-2_YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23.sdr/Whence-Energy-
2_YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23bbd37f35b4b251f45c1bf42879a62d70.yjr:
Unknown binary data (unknown) [Low-confidence model best-guess: Intel
80386 COFF (executable), score=76]
Whence-Energy-
2_YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23.sdr/AssetDownloadMetadata.meta: JSON
document (code)
Whence-Energy-2_YI5JSRVWOVJ5MO6EWC57GJKTBZLXXI23.kfx: Unknown binary
data (unknown) [Low-confidence model best-guess: BMP image data
(image), score=89]

So except for one file, it's still a mystery what e-mailing a PDF to a
Kindle reader with "convert" (without quotes) in the subject actually
produces. The Kindle reader can read it, but so far nothing else I've
tried can. In the end, I want to edit it and re-publish it on Amazon.

okular thinks the .kfx file is a mobipocket, but can't open it. It
doesn't know what the .yjf or .yjr files are.

So, back to trying to find a competent PDF -to- ePub or PDF -to- mobi
converter (I haven't yet tried texmate to create a mobi or ePub from
the LaTeX).

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[Curt]

On 2024-06-27, Richard  wrote:
>
> Have you completely lost it? You should leave this and any other mailing
> lists before you are being sued and kicked out for what you write. And
> trust me, this message of yours is more than enough reason for that.
>

I'm confident I'll be sued for your rudeness and ineptitude, and pass
the rest of my days in some prison devised in your tiny and
ineffectual mind. 

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[Richard]

Have you completely lost it? You should leave this and any other mailing
lists before you are being sued and kicked out for what you write. And
trust me, this message of yours is more than enough reason for that.

Am Do., 27. Juni 2024 um 15:56 Uhr schrieb Curt :

> On 2024-06-26, Van Snyder  wrote:
> >
> > I downloaded everything with the same base name as I sent -- a file and
> > a directory. LibreOffice can't read any of it. Calibre can't read any
> > of it, either in the download or in the mounted Kindle. "file" has no
> > idea what any of the files are.
> >
>
> This is indeed a regrettable outcome to a good-faith suggestion.
>
> One is led to wonder at times why you technical (the term used quite
> loosely in your case) people prove to be so often such intolerable
> asswipes, but I'm not losing much sleep over it, though the higher
> echelons of your generally uncultured ilk seem to be ruling what's left
> of the world.
>
> I'm sure, though, that the latter will continue on despite everything,
> while the former will lie sooner or later permanently horizontal.
>
>

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[Curt]

On 2024-06-26, Van Snyder  wrote:
>
> I downloaded everything with the same base name as I sent -- a file and
> a directory. LibreOffice can't read any of it. Calibre can't read any
> of it, either in the download or in the mounted Kindle. "file" has no
> idea what any of the files are.
>

This is indeed a regrettable outcome to a good-faith suggestion.

One is led to wonder at times why you technical (the term used quite
loosely in your case) people prove to be so often such intolerable
asswipes, but I'm not losing much sleep over it, though the higher
echelons of your generally uncultured ilk seem to be ruling what's left
of the world.

I'm sure, though, that the latter will continue on despite everything,
while the former will lie sooner or later permanently horizontal.

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[eben]

On 6/27/24 04:02, Richard wrote:

Am Do., 27. Juni 2024 um 06:33 Uhr schrieb Van Snyder <
van.sny...@sbcglobal.net>:


"file" has no idea what
any of the files are.


> Otherwise, what exactly does "file" or better "file -i" say?

I think you missed that.

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[Richard]

You could try if Googles ML model "magika" can do a better job (available
via pypi). Otherwise, what exactly does "file" or better "file -i" say?
Worst case, you could open the files in a hex editor and google the first
few bits. Chances are the format uses "magic bits", so the first few bits
in hex are identical for all files of that format.

Am Do., 27. Juni 2024 um 06:33 Uhr schrieb Van Snyder <
van.sny...@sbcglobal.net>:

> I downloaded everything with the same base name as I sent -- a file and a
> directory. LibreOffice can't read any of it. Calibre can't read any of it,
> either in the download or in the mounted Kindle. "file" has no idea what
> any of the files are.
>
>
>

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[Van Snyder]

On Tue, 2024-06-25 at 13:26 +, Curt wrote:
> On 2024-06-24, Van Snyder  wrote:
> > 
> > I composed a book in LaTeX because I wanted the equations to be set
> > correctly -- and because I've been using LaTeX for decades and am
> > most
> > comfortable using it.
> > 
> 
> All I know is if I send a pdf file to my Kindle with the word
> "convert"
> in the subject line (without the quotes), the file is converted to
> the
> Kindle format. I gleaned this *astuce* sometime, somewhere, that has
> since been forgotten.
> 
> I haven't performed this maneuver in a fairly long while, though, so
> things may have changed. Sometimes you are required to run as fast as
> you
> as you can in order to remain in the same place.

The file was indeed sent to my Kindle, and it didn't land as a PDF. I
can read it in the Kindle reader. The table of contents is a mess.
Tables are a mess.

I downloaded everything with the same base name as I sent -- a file and
a directory. LibreOffice can't read any of it. Calibre can't read any
of it, either in the download or in the mounted Kindle. "file" has no
idea what any of the files are.

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[Curt]

On 2024-06-24, Van Snyder  wrote:
>
> I composed a book in LaTeX because I wanted the equations to be set
> correctly -- and because I've been using LaTeX for decades and am most
> comfortable using it.
>

All I know is if I send a pdf file to my Kindle with the word "convert"
in the subject line (without the quotes), the file is converted to the
Kindle format. I gleaned this *astuce* sometime, somewhere, that has
since been forgotten.

I haven't performed this maneuver in a fairly long while, though, so
things may have changed. Sometimes you are required to run as fast as you
as you can in order to remain in the same place. 

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[Van Snyder]

On Tue, 2024-06-25 at 08:59 +1000, David wrote:
> On Mon, 2024-06-24 at 22:42 +, Russell L. Harris wrote:
> > tex4ht may be of use to you.  I love the package.
> That's what Texmaker employs to translate LaTeX to HTML.

It couldn't find the tfm file for the fonts that Amazon recommended.
pdflatex had no trouble finding it.

> Cheers!

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[David]

On Mon, 2024-06-24 at 22:42 +, Russell L. Harris wrote:
> tex4ht may be of use to you.  I love the package.

That's what Texmaker employs to translate LaTeX to HTML.

Cheers!

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[Russell L. Harris]

tex4ht may be of use to you.  I love the package.

RLH

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[Van Snyder]

On Tue, 2024-06-25 at 04:55 +0800, Bret Busby wrote:
> Why not simply publish it as a PDF file?

It's available on Amazon in print-on-demand (paperback or hardback)
which I did indeed publish as PDF. But Amazon doesn't let you upload a
PDF to be published for Kindle readers. They accept only Windoze M$
Word, ePub, and mobi.

Re: ePub or mobi from LaTeX or PDF?

[Van Snyder]

On Mon, 2024-06-24 at 20:15 +, Michael Kjörling wrote:
> On 24 Jun 2024 13:01 -0700, from van.sny...@sbcglobal.net (Van
> Snyder):
> > How do I create an ePub (or mobi) from LaTeX or PDF?
> 
> Since epub is basically a zip archive of HTML, CSS and image files
> plus a small amount of metadata, I would start by looking for
> something to convert LaTeX to modern HTML.

I had "help" to convert my PDF to ePub. They didn't send me the KPF,
but I eventually got Amazon Authors' Support to send it to me. She
warned it's not editable. I unzipped it and found my original PDF, plus
hundreds of "metadata" files that appeared to be mySQL stuff. And my
"helper" wants $$$ to correct a few typos that I had no trouble
correcting in the print-on-demand versions simply by uploading new
PDFs.

> Once you have HTML, the next step (generating an epub out of it)
> should be relatively trivial, possibly to the point that you could
> even do it manually.

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[Richard]

First weapon of choice when trying to convert document formats would be
pandoc. Have a look at it, it can handle quite a lot of formats.  Other
than that, there are guides like this [1], but it looks to me that you
should just stick to LaTeX, as it's the best solution for typesetting,
especially equations. In theory, at least ePub does support equations, but
it's questionable if they even come close to the capabilities of LaTeX
equations. So it's not that unlikely that you'd just do what [1] explains
in a far too complicated way (seriously, have LaTeX equations be run
through a boat load of programs just to get a png? If ePub/mobi don't
support svg, just create the PDF from LaTeX and convert e.g. on GUI with
Inkscape or on CLI with ImageMagick).

But for a book, I kinda doubt any of these solutions would be feasible. The
chance of lots of issues is just too big. So if you must create a ePub
file, better transfer the text manually into a program designed for this
job and insert the equations as images. Will be a lot of work, but chances
are it won't be more work than jumping through a bunch of hoops and ending
up having to redo all formatting either way afterwards.

Best
Richard


[1]: https://minireference.com/blog/generating-epub-from-latex/

Re: ePub or mobi from LaTeX or PDF?

[David]

On Mon, 2024-06-24 at 20:15 +, Michael Kjörling wrote:
> On 24 Jun 2024 13:01 -0700, from [van.sny...@sbcglobal.net](mailto:van.sny...@sbcglobal.net) (Van Snyder):
> 
> > How do I create an ePub (or mobi) from LaTeX or PDF?
> 
> 
> Since epub is basically a zip archive of HTML, CSS and image files  
> plus a small amount of metadata, I would start by looking for  
> something to convert LaTeX to modern HTML.

There are packages in Debian that will do that for you.
Some LaTeX editors, like Texmaker, provide direct access to facilitate that.

 
> Once you have HTML, the next step (generating an epub out of it)  
> should be relatively trivial, possibly to the point that you could  
> even do it manually.

Cheers! 

Re: ePub or mobi from LaTeX or PDF? (was PDF editors)

[Bret Busby]

On 25/6/24 04:01, Van Snyder wrote:
I composed a book in LaTeX because I wanted the equations to be set 
correctly -- and because I've been using LaTeX for decades and am most 
comfortable using it.


How do I create an ePub (or mobi) from LaTeX or PDF?

I tried latex2ebook, which is based on latex2html. It crashes a few 
pages in.


I tried calibre. I tried pdf2ebook. They just make a mess of equations 
and tables. I didn't scroll through the mess to check how well included 
graphics were done.




Why not simply publish it as a PDF file?

..
Bret Busby
Armadale
West Australia
(UTC+0800)
..

Re: ePub or mobi from LaTeX or PDF?

[Michael Kjörling]

On 24 Jun 2024 13:01 -0700, from van.sny...@sbcglobal.net (Van Snyder):
> How do I create an ePub (or mobi) from LaTeX or PDF?

Since epub is basically a zip archive of HTML, CSS and image files
plus a small amount of metadata, I would start by looking for
something to convert LaTeX to modern HTML.

Once you have HTML, the next step (generating an epub out of it)
should be relatively trivial, possibly to the point that you could
even do it manually.

-- 
Michael Kjörling  https://michael.kjorling.se
“Remember when, on the Internet, nobody cared that you were a dog?”

ePub or mobi from LaTeX or PDF? (was PDF editors)

[Van Snyder]

I composed a book in LaTeX because I wanted the equations to be set
correctly -- and because I've been using LaTeX for decades and am most
comfortable using it.

How do I create an ePub (or mobi) from LaTeX or PDF?

I tried latex2ebook, which is based on latex2html. It crashes a few
pages in.

I tried calibre. I tried pdf2ebook. They just make a mess of equations
and tables. I didn't scroll through the mess to check how well included
graphics were done.

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[Thomas Schmitt]

Hi,

Max Nikulin wrote:
> I admit "dithering" may be incorrect term, [...]
> Consider 2 squares having size of 2.5×2.5 pixels. Non-even sizes and fuzzy
> lines variants:
> █████
> ██████
> ████ ██
>██ ██
>█████
> Second variant might have sense if an image is treated as a photo unlikely
> having regular patterns with horizontal and vertical lines.

I see ...
The second rendering style is probably best described as "Bad Distortion".


Have a nice day :)

Thomas

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[Max Nikulin]

On 20/03/2024 01:51, Thomas Schmitt wrote:

Max Nikulin wrote:

When vector graphics, that does not match device resolution, is rasterized,
the result is either non-even sizes of similar elements or fuzzy lines due
to dithering.


Nitpicking:

"Dithering" in raster graphics is emulation of color resolution at the
expense of space resolution.

[...]


The fuzzy lines are rather the opposite. They use surplus color
resolution to emulate ibetter spacial resolution. Over here the usual
term is "Anti-aliasing".


I admit "dithering" may be incorrect term, but I am in doubts if that 
printer (claimed to have 300dpi resolution, but not suitable for QR 
codes) has surplus color resolution. I do not mean anti-aliasing in the 
sense of adjusting pixels darkness (and color).


Consider 2 squares having size of 2.5×2.5 pixels. Non-even sizes and 
fuzzy lines variants:


█████
██████
████ ██
   ██ ██
   █████

Second variant might have sense if an image is treated as a photo 
unlikely having regular patterns with horizontal and vertical lines.

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[Thomas Schmitt]

Hi,

Max Nikulin wrote:
> When vector graphics, that does not match device resolution, is rasterized,
> the result is either non-even sizes of similar elements or fuzzy lines due
> to dithering.

Nitpicking:

"Dithering" in raster graphics is emulation of color resolution at the
expense of space resolution. Multiple coarsly colored pixels together
create the impression of a finer color tone. A certain random aspect is
added to prevent unwanted patters.
  https://en.wikipedia.org/wiki/Dither

The fuzzy lines are rather the opposite. They use surplus color
resolution to emulate ibetter spacial resolution. Over here the usual
term is "Anti-aliasing".
  https://en.wikipedia.org/wiki/Line_drawing_algorithm
  https://www.geeksforgeeks.org/antialiasing/
I get a suspiciously high share of german language results when
searching this term in the web. But "Computer Grapics" by Foley, Van Dam,
Feiner, Hughes of 1990 has a dozen occurences in its Index.


Have a nice day :)

Thomas

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[Max Nikulin]

On 13/03/2024 12:25, hw wrote:

On Mon, 2024-03-11 at 23:45 +0700, Max Nikulin wrote:

It seems you expect some number that you can use for any QR code. There
is no size that fits for all codes.


It's because you said: "I believed that 300dpi is high enough
resolution for QR-codes of reasonable size if source image has proper
quality." that I keep asking what you consider a reasonable size.


QR codes with more modules must be printed at larger size. Isn't it obvious?

By the way, is 300dpi real resolution of your printer or it is 
over-resolution achieved with overstrike with some offset? If so, does 
the printer driver take it into account?



Out of curiosity I tried to scan a QR code printed on a thermal printer
(so likely having ~200dpi resolution) having size of approximately 0.8in
and 50 pixels (modules) per inch. It encodes a 69 bytes long link.


Did you successfully scan it?


Instantly, no trouble at all.


It limits amount of information you may put into QR codes. You can still
choose to use e.g. 4,5,6, etc. printer dots per QR code module.


How can I choose that?  I don't know that there would be an option
with pdflatex or pdf or the printer driver that would let me choose
how many dots per module the printer puts onto the label.


When a code is generated you can look at it and count its modules. The 
next step is simple math. You have resolution, dots per module and 
number of modules, so you can get size and rerun LaTeX.



When I zoom in on QR-codes in a PDF viewer, they don't get blurry.
Perhaps the pst-barcode package uses vector graphics?


Nice, however you have to adjust size to avoid blurring.


How do you mean?  I thought vector graphics don't blur when scaled.


When vector graphics, that does not match device resolution, is 
rasterized, the result is either non-even sizes of similar elements or 
fuzzy lines due to dithering.


If a few multiplications and divisions is so hard problem and each QR 
code module occupy at least 3x3=9 printer dots then I would try to 
rotate the code by e.g. 30 or 45 degrees before printing.

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[jeremy ardley]

On 14/3/24 17:47, jeremy ardley wrote:
For reference on a 203 DPI (8 dots per mm) printer, a GS1-128 barcode 
takes up 12 modules per character. The minimum size of a module is 1 
pixel so 1 character is 12 pixels wide or 1.2mm on a 203 dpi printer.


Assuming a 40 character barcode at 1 pixel per module, it will span 48mm.

However it is very unusual to have 1 pixel per module. Instead at 2 
pixels per module the barcode is 96mm and at 3 pixels it will be 144mm



My error; The character spacing is 1.5mm at 203dpi. So 40 characters is 
60mm at 1 pixel per module, 120mm at 2 pixels per module, and 180mm at 3 
pixels per module. This means for a 40 character barcode you can at best 
print at 2 pixels per module on a typical 100x150m shipping label. This 
allows for no errors in quantization of pixel sizes and It's really hard 
to do with a printing system that does not start and continue with 
accurate pixel registration.

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[jeremy ardley]

On 14/3/24 06:59, hw wrote:

Manufacturers can provide CUPS drivers as well, but the barcode
application is usually only windows.

In my case I had to write my own CUPS driver as the manufacturer does
not provide one.

How did you do that?


It is simply a C program that gets given some parameters and a bitmap by 
CUPS


The program processes the bitmap and frames it with printer commands to 
place the bitmap on the printer page.


CUPS abstracts the actual device interface (in my case USB). But in 
development I wrote the code to send commands directly to the USB device





Getting back to pixel registration, the latex CUPS route is very
unlikely to work well.

It's working great here since years.  Barcodes are no problem, only qr
codes can't be scanned.



This surprises me greatly. 2D codes have very large features compared to 
barcodes. They should be relatively immune to pixel quantization.


For reference on a 203 DPI (8 dots per mm) printer, a GS1-128 barcode 
takes up 12 modules per character. The minimum size of a module is 1 
pixel so 1 character is 12 pixels wide or 1.2mm on a 203 dpi printer.


Assuming a 40 character barcode at 1 pixel per module, it will span 48mm.

However it is very unusual to have 1 pixel per module. Instead at 2 
pixels per module the barcode is 96mm and at 3 pixels it will be 144mm


With the barcode you have no leeway in the pixel sizes. You must have it 
exact to scan.


In comparison, a QR code typically will have modules 8 pixels square and 
typically is 26x26 or 32x32 pixels. At 26x26  the printed code is 26mm 
square at 203dpi. You can afford to be out by a pixel at those dimensions.


If you have problems scanning QR codes at those sizes perhaps your QR 
codes are invalid to start with? If you print them out really large will 
they scan?

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[hw]

On Wed, 2024-03-13 at 03:50 +0800, jeremy ardley wrote:
> On 12/3/24 21:21, hw wrote:
> > 
> > Even if they did that, it would be totally useless because it won't be
> > able to automatically print labels from databases.
> 
> The manufacturer applications  usually allow you to print a list from a 
> spreadsheet or text file.

That isn't very useful.

> > > It is possible to use document generation tools like latex and printing
> > > systems like CUPS to print a label, but pixel registration will be poor.
> > Why?  The manufacturer provided a CPUS printer driver without which
> > printing wouldn't be possible at all.
> 
> Most custom barcodes programs run on windows and don't use CUPS.

That makes them entirely useless.

> Manufacturers can provide CUPS drivers as well, but the barcode 
> application is usually only windows.
> 
> In my case I had to write my own CUPS driver as the manufacturer does 
> not provide one.

How did you do that?

> Getting back to pixel registration, the latex CUPS route is very 
> unlikely to work well.

It's working great here since years.  Barcodes are no problem, only qr
codes can't be scanned.



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Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[Max Nikulin]

On 13/03/2024 02:50, jeremy ardley wrote:
Getting back to pixel registration, the latex CUPS route is very 
unlikely to work well.


TeX with MetaFont fonts worked well with low resolution dot matrix 
printers. Rasterized fonts may be generated for specified resolution. It 
should be still possible unless wide Unicode coverage is required.


I may be wrong, but I have impression that better support of modern 
vector fonts (TTF, OTF, etc.) in LuaTeX has other side. HurfBuz font 
library with priority to speed can not align characters to specified 
pixel grid. Likely nobody cares concerning font hints for low resolution 
devices.


Scale and position of images like QR codes should be adjusted to printer 
resolution.


More than a decade ago it was necessary to provide a document for 
archival purposes. I got a couple of complains: font with too thin lines 
and gray rather than black toner. The cartridge was refilled almost a 
dozen of times, but for routine documents quality was still good. 
CM-Super Type 1 font (converted from original Computer Modern with 
additions related to more scripts) really has hairlines. I configured 
metafont to increase minimal line width and generated a document with 
600dpi raster fonts using latex+dvips+ps2pdf instead of pdflatex. I went 
to a print shop nearby with hope to find there a printer filled with 
really black toner. The person there did not get the point why I was not 
satisfied looking into a test page from my document. It was blurry. 
Likely the page was scaled to printable area and dithering was applied. 
I preferred to go to another shop and got a stack of paper printed with 
proper quality. Either stuff there were a bit more experienced or 
default printer settings were more reasonable.


So it is not difficult to ruin efforts invested into print quality by 
inappropriate checkbox. The process is not fool-proof.

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[Florent Rougon]

Florent Rougon  wrote:

>   - printer matrix alignment if printer resolution is low (more
> difficult; maybe try with some very small horizontal and veritical
> shifts to see if it helps...).

Thinking about it more, this is probably hopeless unless printer
resolution is *extremely* low. Typical printer dots are so small that
you can't realistically expect paper placement to have good enough
precision to align both grids (say, 1/4 of the printer dot size).

This is, I believe, what Jeremy meant when he wrote earlier in this
thread:

> Getting back to pixel registration, the latex CUPS route is very unlikely to
> work well. However a custom application that generates a pixel perfect bitmap
> that is printed at 100% scale through cups should work.

I agree with that if printer resolution is so low that the QR code and
printer dot grids have to be aligned. Even with perfect size in the PDF,
there is very little hope that paper will be every time correctly
aligned in the vertical and horizontal directions with the matrix of
dots managed by the printer—a dot at 300 dpi being approximately
0.08 mm. The only realistic hopes are:
  - high enough resolution that grid alignment doesn't really matter (is
300 dpi enough? Maybe.);
  - direct control over the printer bitmap (what Jeremy mentioned).

For the sake of completeness, the following LaTeX document (an inline
attachment) draws a QR code whose modules are correctly placed for some
“ideal” 300 dpi printer. This assumes that printer dots perfectly start
at a dot-size multiple from the top left corner of the physical page,
which probably can't be obtained in practice. So, this is mainly to show
how accurate placement and computations can be done (\fpeval is provided
by xfp; it is very accurate and expandable).

\documentclass{article}
\usepackage[papersize={50mm,35mm},margin=0cm]{geometry}
\usepackage{xfp}
\usepackage{qrcode}

\pagestyle{empty}
\newlength{\modulesize}
\setlength{\modulesize}{\fpeval{6/300}in}% assume 300 dpi, set 6 dots/module

\begin{document}

\noindent
\hspace{10\modulesize}% horizontal offset from paper edge: 10 modules
\raisebox{\dimexpr \topskip - \height - 10\modulesize}{% ditto in vert. direction
  \qrcode[height=25\modulesize, version=2]{Hey Debian-user!}}%
% The modules will have the expected size only if the QR code is effectively
% doable at version=2 (check the LaTeX terminal output). Indeed, version=2
% means 25×25 modules.

\end{document}

Regards

-- 
Florent

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[Florent Rougon]

hw  wrote:

>> That is quite likely: the pst- prefix means this is PSTricks, which is
>> an oldish way of doing vector graphics with LaTeX. I tend to avoid
>> PSTricks these days as it is generally awkward to use in PDF contexts,
>> although there are various workarounds that often allow to do so.
>
> Is that bad?  It works great for what I'm doing.

Well, “bad” is a strong word in this context. ;-) First, PDF has been
replacing PostScript in the last 20+ years, so it is often easier to
find tools that do interesting things with PDF than with PostScript.

Second, regarding the existing workarounds that allow PSTricks code to
be used in PDF workflows: I haven't used many of them but AFAIK, most of
the times, if you want things to work automatically, you need to enable
\write18 which has security implications. In the most relaxed case, it
allows the compiled document, as well as any class or package it loads,
to run arbitrary shell commands. There is a restricted mode for \write18
(see -shell-restricted and “§5.5 Shell escapes” in `texdoc web2c`), but
it currently doesn't allow running ps2pdf:

,[ /usr/share/texmf/web2c/texmf.cnf ]
| shell_escape_commands = \
| bibtex,bibtex8,\
| extractbb,\
| gregorio,\
| kpsewhich,\
| makeindex,\
| memoize-extract.pl,\
| memoize-extract.py,\
| repstopdf,\
| r-mpost,\
| texosquery-jre8,\
| 
| % we'd like to allow:
| % dvips - but external commands can be executed, need at least -R1.
| % epspdf, ps2pdf, pstopdf - need to respect openout_any,
| %   and gs -dSAFER must be used and check for shell injection with filenames.
| ...
`

One of the problems with PostScript is that it is “too powerful” for
something that should only produce text and graphics—AIUI, security
concerns were not at the core of its design.

Finally, for a few things like transparency and “new” font formats
(e.g., TrueType, OpenType), PostScript is either a no-go or has
solutions that appeared very late, contrary to PDF.

>> The ubiquitous, powerful and modern way to do vector graphics in LaTeX
>> is PGF/TiKZ[1],
>
> That package has almost 1300 pages of documentation which doesn't seem
> to mention qr-codes or barcodes.

Right. Presumably, the qrcode package is good enough. BTW, since its
\qrcode command produces a TeX box without using any TikZ code, it can
be placed without restriction in a TikZ node (I say this because TikZ
nodes can't be nested—more precisely, doing so is not supported).

> I wonder why it uses different options for URLs and other data.  What
> difference does that make?

I believe you misunderstood the manual here, or maybe I don't understand
what you meant. The \qrcode command can encode both URLs and other text.
What I see is simply options (and the starred variant \qrcode*) to
decide whether to turn the QR codes into PDF hyperlinks.

Global switch at \usepackage level:  hyperlinks/nolinks
Local switch for each \qrcode command:   link/nolink

\qrcode*{…} == \qrcode[nolink]{…}

These options are provided because when the hyperref package is loaded,
QR codes are output as hyperlinks by default; however, it is quite
possible to write QR codes that don't encode URLs, in which case making
them hyperlinks would be confusing and useless.

> It might be worth a try for when I need to experiment with qr-codes on
> small labels again.  It might not work because I may need to place the
> qr-code in some way and it could conflict with other packages like the
> labels package ...  I even might have already tried it; it's been a
> few years and I don't remember exactly.

Since \qrcode outputs a TeX box without using any TikZ code, it has
about the highest level of “compatibility” you can expect in a TeX
document.

> Now I'm wondering why the qr-codes I printed with the label printer
> couldn't be reliably scanned.  When I look at [1] and [2], for the
> data I wanted to print (between 38 and 40 alphanumericals at L
> quality) I would have to use a version 2 qr code, i. e. 25x25 modules.
> I don't know how the modules transfer to dots, but assuming the
> minimum of 4 dots per module, it would take 25 x 4 dots, i. e. 100
> dots.  Each module would be 0.33mm in size which would require 25 x
> 0.33mm, i. e. 8.25mm for the size of the qr-code.
>
> I printed the qr-code much larger than that, about 1x1".  That is
> about three times as large as would be required, and the printer can
> print three times as many dots per inch as the 100 dots needed.
>
> So in theory, my theory that the resolution of the printer is too low
> can't be true.
>
> But why couldn't these qr-codes be scanned?  It shouldn't have been a
> problem at all.

L quality is the worst; can't you use a better one? Also worth
considering:

  - scanner limitation? Did you try to scan the codes with a smartphone?

  - printer matrix alignment if printer resolution is low (more
difficult; maybe try with some very small horizontal and veritical
shifts to see if it helps...).

Regards

-- 
Florent

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[hw]

On Mon, 2024-03-11 at 23:45 +0700, Max Nikulin wrote:
> On 11/03/2024 08:06, hw wrote:
> > On Sun, 2024-03-10 at 09:50 +0700, Max Nikulin wrote:
> > > On 10/03/2024 04:41, hw wrote:
> > > > \psbarcode{textblah foo}{height=0.6 width=0.6 eclevel=L}{qrcode}
> > > > 
> > > > That works for 600dpi laser printers.  When you print the QR-code with
> > > > a 300dpi label printer you can't reliably scan it, not even when you
> > > > make the QR-code 1x1" in size.
> > > > 
> > > > Perhaps that's not a reasonable size?
> > > 
> > > Perhaps height and width are chosen improperly. An image some percents
> > > smaller may be sharper.
> > 
> > What size do you consider reasonable?
> 
> It seems you expect some number that you can use for any QR code. There 
> is no size that fits for all codes.

It's because you said: "I believed that 300dpi is high enough
resolution for QR-codes of reasonable size if source image has proper
quality." that I keep asking what you consider a reasonable size.

> Out of curiosity I tried to scan a QR code printed on a thermal printer 
> (so likely having ~200dpi resolution) having size of approximately 0.8in 
> and 50 pixels (modules) per inch. It encodes a 69 bytes long link. 
> Likely the same code scaled to 0.4in will still work, but I would prefer 
> to avoid it, 0.6in should be more reliable. On your 300dpi printer this 
> particular QR code may be printed e.g. at ~(0.8/1.5)in.

Did you successfully scan it?

> > [...]
> > The QR-code must fit on the label, plus some text.  The labels are
> > 50x35mm in size.
> 
> It limits amount of information you may put into QR codes. You can still 
> choose to use e.g. 4,5,6, etc. printer dots per QR code module.

How can I choose that?  I don't know that there would be an option
with pdflatex or pdf or the printer driver that would let me choose
how many dots per module the printer puts onto the label.

> > When I zoom in on QR-codes in a PDF viewer, they don't get blurry.
> > Perhaps the pst-barcode package uses vector graphics?
> 
> Nice, however you have to adjust size to avoid blurring.

How do you mean?  I thought vector graphics don't blur when scaled.



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Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[hw]

On Mon, 2024-03-11 at 11:58 +0100, Florent Rougon wrote:
> Hi,
> 
> I haven't read the whole thread (sorry) but thought this might help.
> 
> hw  wrote:
> 
> > When I zoom in on QR-codes in a PDF viewer, they don't get blurry.
> > Perhaps the pst-barcode package uses vector graphics?
> 
> That is quite likely: the pst- prefix means this is PSTricks, which is
> an oldish way of doing vector graphics with LaTeX. I tend to avoid
> PSTricks these days as it is generally awkward to use in PDF contexts,
> although there are various workarounds that often allow to do so.

Is that bad?  It works great for what I'm doing.

> The ubiquitous, powerful and modern way to do vector graphics in LaTeX
> is PGF/TiKZ[1],

That package has almost 1300 pages of documentation which doesn't seem
to mention qr-codes or barcodes.

> however this is not even necessary for QR codes, because
> [...]

good :)

> I've played with a different package for producing QR codes in LaTeX,
> which uses the aforementioned \hrule and \vrule primitives: qrcode. Its
> manual is here (follow the “Package documentation” link):
> 
>   https://ctan.org/pkg/qrcode

I wonder why it uses different options for URLs and other data.  What
difference does that make?

> Here is a simple example you can compile with pdflatex:
> 
> \documentclass{article}
> \usepackage{qrcode}
> 
> \pagestyle{empty}
> 
> \begin{document}
> 
> \noindent
> % \qrset affects \qrcode commands in the current group. You can use it
> % to factor out options used for several QR codes.
> \qrset{nolinks, padding}% add padding to make sure the codes are 
> “legal”/readable
> \qrcode[version=1]{Hey Debian-user!}% Can't do version=1 with level=M or more
> \qrcode[level=L, version=1]{Hey Debian-user!}% Less redundancy but is doable
> 
> \end{document}
> 
> Note the terminal output:
> 
> 
> 
>  Version increased to '2' to fit text.>
> 
> 
>  calculated.>
> 
> 
> 
> 
>  calculated.>
> 

It might be worth a try for when I need to experiment with qr-codes on
small labels again.  It might not work because I may need to place the
qr-code in some way and it could conflict with other packages like the
labels package ...  I even might have already tried it; it's been a
few years and I don't remember exactly.

> [...]
> But with low printer resolution constraints, who knows?).
> 
> Hope this helps!

Yes, thanks, knowing about these packages can be useful.

Now I'm wondering why the qr-codes I printed with the label printer
couldn't be reliably scanned.  When I look at [1] and [2], for the
data I wanted to print (between 38 and 40 alphanumericals at L
quality) I would have to use a version 2 qr code, i. e. 25x25 modules.
I don't know how the modules transfer to dots, but assuming the
minimum of 4 dots per module, it would take 25 x 4 dots, i. e. 100
dots.  Each module would be 0.33mm in size which would require 25 x
0.33mm, i. e. 8.25mm for the size of the qr-code.

I printed the qr-code much larger than that, about 1x1".  That is
about three times as large as would be required, and the printer can
print three times as many dots per inch as the 100 dots needed.

So in theory, my theory that the resolution of the printer is too low
can't be true.

But why couldn't these qr-codes be scanned?  It shouldn't have been a
problem at all.


[1]: https://www.qrcode.com/en/about/version.html
[2]: https://www.qrcode.com/en/howto/cell.html

> 
> Regards
> 
> [1] https://ctan.org/pkg/pgf
> 





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Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[jeremy ardley]

On 12/3/24 21:21, hw wrote:


Even if they did that, it would be totally useless because it won't be
able to automatically print labels from databases.


The manufacturer applications  usually allow you to print a list from a 
spreadsheet or text file.



It is possible to use document generation tools like latex and printing
systems like CUPS to print a label, but pixel registration will be poor.

Why?  The manufacturer provided a CPUS printer driver without which
printing wouldn't be possible at all.


Most custom barcodes programs run on windows and don't use CUPS.

Manufacturers can provide CUPS drivers as well, but the barcode 
application is usually only windows.


In my case I had to write my own CUPS driver as the manufacturer does 
not provide one.


Getting back to pixel registration, the latex CUPS route is very 
unlikely to work well. However a custom application that generates a 
pixel perfect bitmap that is printed at 100% scale through cups should work.


There are a number of programs that can do that, though I have not used 
them so far.


- zint

- GNU barcode

- BWIPP

also a possibility is

- qrencode

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[hw]

On Mon, 2024-03-11 at 09:57 +0800, jeremy ardley wrote:
> On 11/3/24 07:34, hw wrote:
> > Do you think that thermal transfer printers with 203dpi would be
> > better suited to print QR codes than the 300dpi multi-mode printers?
> > 
> > I'm not fond of thermal transfer at all.  Usually what is being
> > printed that way fades rather quickly over time and is more slightly
> > gray rather than black and so thin that it's hard to read even when
> > freshly printed.  Perhaps better labels are available, but the labels
> > must not get too expensive ...
> 
> 
> Thermal transfer and thermal direct printers have the same resolution.
> 
> Thermal transfer printers are used for archival labels as they fade very 
> little over time.
> 
> Direct thermal printers are intended for mailing applications where it 
> doesn't matter if they fade after a few months.
> 
> Given that, I think a lot of commercial shippers use thermal transfer 
> for mailing labels. Very few shippers use laser printed adhesive address 
> label, nor non-adhesive in pockets or pouches.
> 
> To print a QR code or other 2D code on any thermal printer, the printer 
> manufacturer will supply an application that generate the codes and 
> prints them independently of the host printing system. These codes will 
> scan perfectly.

Even if they did that, it would be totally useless because it won't be
able to automatically print labels from databases.

> It is possible to use document generation tools like latex and printing 
> systems like CUPS to print a label, but pixel registration will be poor. 

Why?  The manufacturer provided a CPUS printer driver without which
printing wouldn't be possible at all.

> The only practical option for this route is to print the code BIG
 
That's what I thought, but then the codes won't fit on the labels.
That's why I wonder if there's a better way.



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Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[Max Nikulin]

On 11/03/2024 08:06, hw wrote:

On Sun, 2024-03-10 at 09:50 +0700, Max Nikulin wrote:

On 10/03/2024 04:41, hw wrote:

\psbarcode{textblah foo}{height=0.6 width=0.6 eclevel=L}{qrcode}

That works for 600dpi laser printers.  When you print the QR-code with
a 300dpi label printer you can't reliably scan it, not even when you
make the QR-code 1x1" in size.

Perhaps that's not a reasonable size?


Perhaps height and width are chosen improperly. An image some percents
smaller may be sharper.


What size do you consider reasonable?


It seems you expect some number that you can use for any QR code. There 
is no size that fits for all codes.


Out of curiosity I tried to scan a QR code printed on a thermal printer 
(so likely having ~200dpi resolution) having size of approximately 0.8in 
and 50 pixels (modules) per inch. It encodes a 69 bytes long link. 
Likely the same code scaled to 0.4in will still work, but I would prefer 
to avoid it, 0.6in should be more reliable. On your 300dpi printer this 
particular QR code may be printed e.g. at ~(0.8/1.5)in.


Fix size of QR code pixel (module), not size of whole QR code.


- Find number of pixels in QR code in QR specs (or just calculate them)


Calculate them how or find them where?  Pdflatex somehow does it and
the QR-codes are fine when printed on a laser printer and when shown
on a 4k display.


"Modules" in Florent's message is what I referred to as QR code "pixels" 
and their count depends on "version".



- Specify width and height so that the ration of 2 numbers above is a
whole number.

Image may become a bit larger or a bit smaller.


The QR-code must fit on the label, plus some text.  The labels are
50x35mm in size.


It limits amount of information you may put into QR codes. You can still 
choose to use e.g. 4,5,6, etc. printer dots per QR code module.



When I zoom in on QR-codes in a PDF viewer, they don't get blurry.
Perhaps the pst-barcode package uses vector graphics?


Nice, however you have to adjust size to avoid blurring.

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[Florent Rougon]

Hi,

I haven't read the whole thread (sorry) but thought this might help.

hw  wrote:

> When I zoom in on QR-codes in a PDF viewer, they don't get blurry.
> Perhaps the pst-barcode package uses vector graphics?

That is quite likely: the pst- prefix means this is PSTricks, which is
an oldish way of doing vector graphics with LaTeX. I tend to avoid
PSTricks these days as it is generally awkward to use in PDF contexts,
although there are various workarounds that often allow to do so.

The ubiquitous, powerful and modern way to do vector graphics in LaTeX
is PGF/TiKZ[1], however this is not even necessary for QR codes, because
these are made of perfect monochrome rectangles, which TeX can draw
natively using its \hrule and \vrule primitives.

> 'pdfimages -list' doesn't show any images for a PDF with QR-codes
> created with pdflatex.

AFAIK, 'pdfimages' would extract “actual images” embedded in a PDF file
(e.g., PNG or JPG), however here pst-barcode presumably uses PostScript
or PDF primitives for drawing and filling polygons, which in your case
probably end up as PDF primitives. Hence, 'pdfimages' can't see these QR
codes (AFAIUI).

I've played with a different package for producing QR codes in LaTeX,
which uses the aforementioned \hrule and \vrule primitives: qrcode. Its
manual is here (follow the “Package documentation” link):

  https://ctan.org/pkg/qrcode

Here is a simple example you can compile with pdflatex:

\documentclass{article}
\usepackage{qrcode}

\pagestyle{empty}

\begin{document}

\noindent
% \qrset affects \qrcode commands in the current group. You can use it
% to factor out options used for several QR codes.
\qrset{nolinks, padding}% add padding to make sure the codes are 
“legal”/readable
\qrcode[version=1]{Hey Debian-user!}% Can't do version=1 with level=M or more
\qrcode[level=L, version=1]{Hey Debian-user!}% Less redundancy but is doable

\end{document}

Note the terminal output:














There are several quality levels allowing error correction (see the
manual): Low, Medium, Quality, and High. They correspond to 'level'
values L, M, Q, H. Default is M but if the chosen 'version' (which maps
to a specific number of modules) allows for a better level, qrcode
automatically upgrades to the best level possible for the chosen
'version' (which the above log demonstrates for the first QR code).

My example tries to print two QR codes with version=1, which means
21×21 modules (see below). Using the default level (M), this is not
possible for the specified text, therefore the first QR code is drawn as
a version=2 one (i.e., it has 25×25 modules). For the second QR code, I
explicitly ask for level=L which has the worst redundancy for error
correction; this allows "Hey Debian-user!" to be QR-encoded with
version=1, i.e. as a square of 21×21 modules.

The length of what you are encoding obviously dictates which quality
parameters you can afford, so you need to play with actual text for your
application. You can control the size of the QR code with e.g.
\qrcode[height=1cm]{...}. Since the modules are stuck to each other,
once you've determined an appropriate 'version' parameter, you can
easily choose a height that causes the modules to have the exact size
you want in the resulting PDF file (printer driver issues are out of my
league).

Regarding the 'version' parameter:

  version=1  → 21×21 modules
  version=2  → 25×25 modules
  version=3  → 29×29 modules
  ...
  version=40 → 177×177 modules

(each version step adds 4 to the number of modules in each direction)

So, you may want to play with text of yours and these parameters.
Examine the terminal output or log file to make sure the qrcode package
didn't have to increase the 'version' in order to encode the text you
specified. Note that in my example, the second QR code scanned with a
smartphone from a computer screen display seems to be significantly
harder to recognize than the first one (IOW, using level=L is probably a
bad idea even though it allows one to reduce the number of modules. But
with low printer resolution constraints, who knows?).

Hope this helps!

Regards

[1] https://ctan.org/pkg/pgf

-- 
Florent

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[jeremy ardley]

On 11/3/24 07:34, hw wrote:

Do you think that thermal transfer printers with 203dpi would be
better suited to print QR codes than the 300dpi multi-mode printers?

I'm not fond of thermal transfer at all.  Usually what is being
printed that way fades rather quickly over time and is more slightly
gray rather than black and so thin that it's hard to read even when
freshly printed.  Perhaps better labels are available, but the labels
must not get too expensive ...



Thermal transfer and thermal direct printers have the same resolution.

Thermal transfer printers are used for archival labels as they fade very 
little over time.


Direct thermal printers are intended for mailing applications where it 
doesn't matter if they fade after a few months.


Given that, I think a lot of commercial shippers use thermal transfer 
for mailing labels. Very few shippers use laser printed adhesive address 
label, nor non-adhesive in pockets or pouches.


To print a QR code or other 2D code on any thermal printer, the printer 
manufacturer will supply an application that generate the codes and 
prints them independently of the host printing system. These codes will 
scan perfectly.


It is possible to use document generation tools like latex and printing 
systems like CUPS to print a label, but pixel registration will be poor. 
The only practical option for this route is to print the code BIG

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[hw]

On Sun, 2024-03-10 at 09:50 +0700, Max Nikulin wrote:
> On 10/03/2024 04:41, hw wrote:
> > \psbarcode{textblah foo}{height=0.6 width=0.6 eclevel=L}{qrcode}
> > 
> > That works for 600dpi laser printers.  When you print the QR-code with
> > a 300dpi label printer you can't reliably scan it, not even when you
> > make the QR-code 1x1" in size.
> > 
> > Perhaps that's not a reasonable size?
> 
> Perhaps height and width are chosen improperly. An image some percents 
> smaller may be sharper.

What size do you consider reasonable?

> - Find the dpi value in the specs of your printer

300dpi

> - Find number of pixels in QR code in QR specs (or just calculate them)

Calculate them how or find them where?  Pdflatex somehow does it and
the QR-codes are fine when printed on a laser printer and when shown
on a 4k display.

> - Specify width and height so that the ration of 2 numbers above is a 
> whole number.
> 
> Image may become a bit larger or a bit smaller.

The QR-code must fit on the label, plus some text.  The labels are
50x35mm in size.

That limits the QR-code to about 1x1", give or take a few mm.  1" is
already half the width of the label which doesn't leave much room for
text, and you have to give it some slack because you want to end up
printing somewhere on the label and not on the gaps between the
labels.

When I zoom in on QR-codes in a PDF viewer, they don't get blurry.
Perhaps the pst-barcode package uses vector graphics?

'pdfimages -list' doesn't show any images for a PDF with QR-codes
created with pdflatex.



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Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[hw]

On Sun, 2024-03-10 at 07:56 +0800, jeremy ardley wrote:
> On 10/3/24 05:41, hw wrote:
> > The QR-codes are sharp and easily scanable when printed in 600dpi.
> > With the label printer you can't really tell if they're sharp or not.
> 
> As  mentioned in my previous post, thermal label printers are 203dpi, 
> *not the 300 that the OP quoted.*

The printers I've been printing on are 300dpi and can do both thermal
and ribbon/ink.  I haven't tried thermal.

> [...]
> The data_matrix code (like a QRcode) for the same 41 digits is a 26x26 matrix 
> which at 203dpi can have pixels of 8x8 dots in a field of 26x26mm. These are 
> super easy for a thermal printer

Do you think that thermal transfer printers with 203dpi would be
better suited to print QR codes than the 300dpi multi-mode printers?

I'm not fond of thermal transfer at all.  Usually what is being
printed that way fades rather quickly over time and is more slightly
gray rather than black and so thin that it's hard to read even when
freshly printed.  Perhaps better labels are available, but the labels
must not get too expensive ...



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Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[hw]

On Sun, 2024-03-10 at 10:21 +0700, Max Nikulin wrote:
> On 10/03/2024 03:48, jeremy ardley wrote:
> > 
> > Standard thermal label printers are 203DPI (8 dots per mm).
> 
> Thanks, this number suits better to my expectation. I just trusted hw 
> earlier.

I should clarify:

The printer the OP pointed to seems to be rated at 203DPI and I
somehow thought it had 300dpi.  (203 seems very odd.)

The printers I have been trying to print QR-codes on are actually
300dpi printers.  They can do both thermal transfer or use a ribbon
that transfers ink to the labels kinda like typewriters did.  I
haven't used the thermal transfer mode and only the ribbon/ink mode.

> > I have asked the postal service to generate labels at 203dpi which will 
> > print just fine at 600 dpi and so work with laser and thermal printers, 
> > but they will not cooperate.

Why would they create labels that can not be scanned when printed?

Maybe ask them to print the labels for you?  If they can't scan them
then that's their problem.



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Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[jeremy ardley]

On 10/3/24 15:39, Max Nikulin wrote:
From your earlier message I count approximately 1000px for 5in (125 
mm) barcode. If it is 1:1 to ~200dpi then it is incompatible with 
300dpi printers, so it may be a reason why your proposal to the post 
office was rejected. If it is 500 black or white lines and each one 
occupies 2 printer dots then 300dpi image of the same size has 3 dots 
per line. (Sorry, I am unsure concerning "module" term.) You should be 
able to rasterize PDF files to 600dpi (2x factor) and downsample them 
by 1/3 keeping lines sharp.


In barcodes such as Code-128 a module is 12 'slots' which at minimum is 
one pixel per slot or 12 pixels. Code-128 has over 100 character 
encodings in a module.


So code 128 on a 203dpi printer 12 * characters / 8 mm e.g. for 40 
characters it's 12*40/8 = 60mm. 2 pixels per module make it 120mm. 3 
pixels per module make it 180mm so too big for mailing labels.


As for my post office, their barcodes do not match 300dpi or 600dpi. 
They are scaled at about 75-80% of what they should be. I'm really 
surprised they work. I can only guess most people use 1200dpi.


Thermal labels are the way to go as they stick really well and resist 
water. They are also *cheap*. around 1-2 cents in bulk for 100x150 . 
Plastic envelope and laser printed label will cost 10-20c. A self 
adhesive laser label is getting on to 50c.

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[Max Nikulin]

On 10/03/2024 10:51, jeremy ardley wrote:


I have far less problems with the QR code (in my case data_matrix code) 
than with the barcode. The pixel elements of the QR code are much larger 
than the lines in a barcode so there is much less chance for pixel 
ambiguity.


From your earlier message I count approximately 1000px for 5in (125 mm) 
barcode. If it is 1:1 to ~200dpi then it is incompatible with 300dpi 
printers, so it may be a reason why your proposal to the post office was 
rejected. If it is 500 black or white lines and each one occupies 2 
printer dots then 300dpi image of the same size has 3 dots per line. 
(Sorry, I am unsure concerning "module" term.) You should be able to 
rasterize PDF files to 600dpi (2x factor) and downsample them by 1/3 
keeping lines sharp.


Certainly this simple trick would fail if QR in the same file requires 
3/4 scaling.



from pdf2image import convert_from_path


The pdfimage(1) tool may extract images in their original format, 
perhaps there is a similar python module.



     detected_codes = pyzbar.decode(img)


Each barcode and QR code may be resampled individually without 
recognizing it. If position of each image on the page is known,
resampled images may be put back to correct places in the document 
rasterized to your printer resolution.


P.S. Post office guys may believe that labels created using laser 
printers are more resistant to wearing during processing and delivery, 
so 300dpi resolution may be intentional to discourage usage of thermal 
printers.

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[jeremy ardley]

On 10/3/24 11:21, Max Nikulin wrote:


Is the QR image a raster one? I am unsure concerning its printer dots 
per QR pixel ratio. Let's take e.g. 4 as a value inconvenient for 
direct scaling from 300dpi to 203dpi. I expect that upscaling it by 3 
and downscaling the result by 4 with disabled smoothing (e.g. using 
splines) should generate an image that is 1.5% larger than the one 
suitable for 203dpi. So setting 98.5% scaling for printer should allow 
to achieve sharp QR image without re-encoding QR.



In my case I have never seen a bigger dogs breakfast of a pdf! It has 
many elements in different formats including bitmaps, scalable vector 
graphics, and text elements. That and some images are colour and some 
black and white. I just preprocess it


I have far less problems with the QR code (in my case data_matrix code) 
than with the barcode. The pixel elements of the QR code are much larger 
than the lines in a barcode so there is much less chance for pixel 
ambiguity.


I think i you make it 'big enough' it will scan fine. So a factor of 2 
magnification should work with a QR code.


I spent many (un)happy hours with gimp and imagemagick to try and get 
the best solution for barcodes. Sadly there is none other than print the 
barcode as big as possible in your page real-estate.


I spent an hour today with my friend GPT4 and python and I can now pluck 
out any and all codes from my mailing labels and I next plan to generate 
new labels at 203dpi using freshly encoded barcodes and data_matrix codes.


Here is some experimental code

from PIL import Image
import pyzbar.pyzbar as pyzbar
import qrcode  # For generating QR codes
from barcode import EAN13, generate  # Using EAN13 as an example; this 
might vary

from barcode.writer import ImageWriter
import os

from pdf2image import convert_from_path

def pdf_to_image(pdf_path, dpi=600):
    images = convert_from_path(pdf_path, dpi=dpi)
    for img in images:
    yield img

def detect_and_extract_codes(images):
    for img in images:
    detected_codes = pyzbar.decode(img)
    for code in detected_codes:
    print(code)
    if code.type == 'QRCODE':
    # Process QR code
    process_qr_code(code)
    else:
    # Process other types of barcodes
    process_barcode(code)

def process_qr_code(code):
    qr = qrcode.QRCode(
    version=1,
    error_correction=qrcode.constants.ERROR_CORRECT_L,
    box_size=10,
    border=4,
    )
    qr.add_data(code.data.decode())
    qr.make(fit=True)
    img = qr.make_image(fill_color="black", back_color="white")
    img.show()  # Or save the image

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[Max Nikulin]

On 10/03/2024 03:48, jeremy ardley wrote:


Standard thermal label printers are 203DPI (8 dots per mm).


Thanks, this number suits better to my expectation. I just trusted hw 
earlier.


I have asked the postal service to generate labels at 203dpi which will 
print just fine at 600 dpi and so work with laser and thermal printers, 
but they will not cooperate.


Is the QR image a raster one? I am unsure concerning its printer dots 
per QR pixel ratio. Let's take e.g. 4 as a value inconvenient for direct 
scaling from 300dpi to 203dpi. I expect that upscaling it by 3 and 
downscaling the result by 4 with disabled smoothing (e.g. using splines) 
should generate an image that is 1.5% larger than the one suitable for 
203dpi. So setting 98.5% scaling for printer should allow to achieve 
sharp QR image without re-encoding QR.


You may try to find rational approximation for (4*208)/300 better than 
4/3 (or for actual QR pixel size).

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[Max Nikulin]

On 10/03/2024 04:41, hw wrote:

\psbarcode{textblah foo}{height=0.6 width=0.6 eclevel=L}{qrcode}

That works for 600dpi laser printers.  When you print the QR-code with
a 300dpi label printer you can't reliably scan it, not even when you
make the QR-code 1x1" in size.

Perhaps that's not a reasonable size?


Perhaps height and width are chosen improperly. An image some percents 
smaller may be sharper.


- Find the dpi value in the specs of your printer
- Find number of pixels in QR code in QR specs (or just calculate them)
- Specify width and height so that the ration of 2 numbers above is a 
whole number.


Image may become a bit larger or a bit smaller.

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[jeremy ardley]

On 10/3/24 05:41, hw wrote:

The QR-codes are sharp and easily scanable when printed in 600dpi.
With the label printer you can't really tell if they're sharp or not.


As  mentioned in my previous post, thermal label printers are 203dpi, 
*not the 300 that the OP quoted.*


you can read the OP specs here which say 203. 
.


Thermal label printers have no problems printing even long bar codes, QR codes, 
and data_matrix codes if the generator uses the correct dpi and the print 
process maintains the pixel mapping.

In my case my barcodes are 41 digits long (extreme GS1 !) and at 2 pixels per 
module (12 modules per digit) it is 123mm long which fits into a 150x100 
thermal label

The data_matrix code (like a QRcode) for the same 41 digits is a 26x26 matrix 
which at 203dpi can have pixels of 8x8 dots in a field of 26x26mm. These are 
super easy for a thermal printer

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[hw]

On Sat, 2024-03-09 at 23:20 +0700, Max Nikulin wrote:
> On 09/03/2024 19:08, hw wrote:
> > On Fri, 2024-03-08 at 23:21 +0700, Max Nikulin wrote:
> > > On 08/03/2024 12:35, hw wrote:
> > > > On Thu, 2024-03-07 at 23:15 -0500, Jeffrey Walton wrote:
> > > > > 
> > > > > I have a USB thermal printer for the shipping labels,
> > > > > <https://www.amazon.com/gp/product/B08V28J3JS>.
> > > > 
> > > > This printer has only 300dpi.  If you print QR-codes on it make sure
> > > > you can scan them: they have to be large enough or get you an
> > > > unscanable smear.
> > > 
> > > I believed that 300dpi is high enough resolution for QR-codes of
> > > reasonable size if source image has proper quality. On the other hand,
> > > if possible, it is better to scale QR-codes to match some whole factor
> > > of printer pixel size.
> > 
> > What do you consider a 'reasonable size'?
> 
> Looking at a QR code likely having ~75 pixels per inch I find it 
> unreasonably small for delivery labels.

Shipping labels tend to be pretty large.

> I am in doubts if its redundancy is high enough to reliably
> recognize it if it would be scratched during delivery. Another

Increased redundancy can make the QR-code harder or impossible to
scan because it creates more smear instead of more redundancy.

Once you've seen what that looks like, it is evident that smearing
more ink into the same area for more redundancy makes things only
worse.  You'd have to print the QR-code larger.

> limitation may be stability of optics in scanners in respect to
> labels. This one is printed using a laser printer with resolution at
> least 600 dpi. Each QR code pixel has still 4x4 printer dots in the
> case of 300dpi, so when image is properly aligned, printer quality
> is not an issue.

Yes, the QR-codes printed on a 600dpi laser printer are fine.

> > There is no source image other than whatever LaTeX creates.  I can
> > specify the size of the QR-code.  Other than that, how do you apply
> > scaling?
> 
> I am unsure what particular QR code generator do you use and what is the 

I'm using the pst-barcode package and pdflatex to create a PDF file
which is then sent through cups to the printer.  So LaTeX, the
bst-barcode package, some PDF stuff, the printer driver, the printer
and it's settings for darkness and printing speed, the material the
labels are made of and the ribbon with the ink on it which gets
transferred to the label all influence the result.

Also, labels are continuously being fed through the printer while
printing without stopping.  That makes some smear inevitable.

> format of QR codes.

It basically goes like this:

\psbarcode{textblah foo}{height=0.6 width=0.6 eclevel=L}{qrcode}

That works for 600dpi laser printers.  When you print the QR-code with
a 300dpi label printer you can't reliably scan it, not even when you
make the QR-code 1x1" in size.

Perhaps that's not a reasonable size?

> Is it raster or vector image? Specify size that makes QR code pixels
> having whole number of printer pixels.

I only know that the QR-code must fit on the label.

> "Fit to page" or "fit to printable area" in printer options may make an 
> image blurry.

No such options are specified.

> In the case of low input image resolution, upscaling method suitable
> for photos may make QR code blurry. However consistent configuration
> should make QR codes sharp.

IIRC there is an option to create a PDF having a particular
resolution, like 300DPI, but that didn't seem to have any effect.  I
don't remember what that option was :/

The QR-codes are sharp and easily scanable when printed in 600dpi.
With the label printer you can't really tell if they're sharp or not.




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Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[jeremy ardley]

On 10/3/24 00:20, Max Nikulin wrote:


Looking at a QR code likely having ~75 pixels per inch I find it 
unreasonably small for delivery labels. I am in doubts if its 
redundancy is high enough to reliably recognize it if it would be 
scratched during delivery. Another limitation may be stability of 
optics in scanners in respect to labels. This one is printed using a 
laser printer with resolution at least 600 dpi. Each QR code pixel has 
still 4x4 printer dots in the case of 300dpi, so when image is 
properly aligned, printer quality is not an issue. 


Standard thermal label printers are 203DPI (8 dots per mm).

The problem with printing QR codes and bar codes is not the resolution 
of the printer but getting the the software drivers to produce a bitmap 
that is the same resolution as the printer resolution and aligned at the 
pixel level when it goes to the printer


I have written a CUPS driver for a thermal printer and routinely print 
labels with barcodes and QR style codes. I have immense problems with 
PDF labels generated by my local postal service which are generated for 
a 300 DPI printer. The barcodes especially end up with too thick or too 
thin bars where the pixel mapping doesn't align. These will not scan.


I have asked the postal service to generate labels at 203dpi which will 
print just fine at 600 dpi and so work with laser and thermal printers, 
but they will not cooperate.


I am in the process of developing software to take the issued labels, 
extract the barcode and QR fields, decode them, and then generate new 
bitmaps at 203 dpi to replace  the misaligned bitmaps. This is not 
straight forward as the postal service does not fully comply with the 
coding rules.


In the meantime I have to extract the QR and bar code fields, enlarge 
them, and print on separate labels.


As far as printer drivers work, CUPS typically generates a bitmap from a 
source document such as PDF or postscript, and passes that to a raster 
printer. This in itself can be a problem as any stage of the process of 
generation of pdf, 'printing', and rasterisation can misalign and 
distort pixels. To be absolutely sure of clean output you need a custom 
program directly driving the printer.

Re: printing QR-codes on labels with 300dpi label printers with LaTeX

[Max Nikulin]

On 09/03/2024 19:08, hw wrote:

On Fri, 2024-03-08 at 23:21 +0700, Max Nikulin wrote:

On 08/03/2024 12:35, hw wrote:

On Thu, 2024-03-07 at 23:15 -0500, Jeffrey Walton wrote:


I have a USB thermal printer for the shipping labels,
<https://www.amazon.com/gp/product/B08V28J3JS>.


This printer has only 300dpi.  If you print QR-codes on it make sure
you can scan them: they have to be large enough or get you an
unscanable smear.


I believed that 300dpi is high enough resolution for QR-codes of
reasonable size if source image has proper quality. On the other hand,
if possible, it is better to scale QR-codes to match some whole factor
of printer pixel size.


What do you consider a 'reasonable size'?


Looking at a QR code likely having ~75 pixels per inch I find it 
unreasonably small for delivery labels. I am in doubts if its redundancy 
is high enough to reliably recognize it if it would be scratched during 
delivery. Another limitation may be stability of optics in scanners in 
respect to labels. This one is printed using a laser printer with 
resolution at least 600 dpi. Each QR code pixel has still 4x4 printer 
dots in the case of 300dpi, so when image is properly aligned, printer 
quality is not an issue.



There is no source image other than whatever LaTeX creates.  I can
specify the size of the QR-code.  Other than that, how do you apply
scaling?


I am unsure what particular QR code generator do you use and what is the 
format of QR codes. Is it raster or vector image? Specify size that 
makes QR code pixels having whole number of printer pixels.


"Fit to page" or "fit to printable area" in printer options may make an 
image blurry. In the case of low input image resolution, upscaling 
method suitable for photos may make QR code blurry. However consistent 
configuration should make QR codes sharp.

printing QR-codes on labels with 300dpi label printers with LaTeX (was: libbusiness-us-usps-webtools-perl and USPS Ground Advantage shipping)

[hw]

On Fri, 2024-03-08 at 23:21 +0700, Max Nikulin wrote:
> On 08/03/2024 12:35, hw wrote:
> > On Thu, 2024-03-07 at 23:15 -0500, Jeffrey Walton wrote:
> > > 
> > > I have a USB thermal printer for the shipping labels,
> > > <https://www.amazon.com/gp/product/B08V28J3JS>.
> > 
> > This printer has only 300dpi.  If you print QR-codes on it make sure
> > you can scan them: they have to be large enough or get you an
> > unscanable smear.
> 
> I believed that 300dpi is high enough resolution for QR-codes of 
> reasonable size if source image has proper quality. On the other hand, 
> if possible, it is better to scale QR-codes to match some whole factor 
> of printer pixel size.

What do you consider a 'reasonable size'?  The maximum possible size
of the QR-code is limited by the size of the label.  (Shipping labels
are probably big enough ...)

There is no source image other than whatever LaTeX creates.  I can
specify the size of the QR-code.  Other than that, how do you apply
scaling?




signature.asc
Description: This is a digitally signed message part

Re: LaTex Unicode entry issues

[Max Nikulin]

On 27/08/2023 10:23, David wrote:

On Sun, 2023-08-27 at 10:16 +0700, Max Nikulin wrote:

On 26/08/2023 19:08, Haines Brown wrote:

\documentclass[12pt]{article} %
\usepackage[utf8]{inputenc} %
\usepackage[T1]{fontenc} %
\usepackage[greek,english]{babel} % to make Greek charactes
available


It seems, you are overestimating effect. You still need to provide
fontenc containing Greek characters. Unless you have real reasons to
avoid LuaTeX, I recommend you to use lualatex instead of pdflatex.


To be clear, babel does some high level job: loading hyphenation 
patterns, configures \selectlanguage and \foreignlanguage commands. If I 
read docs in /usr/share/doc/texlive-doc/generic/babel-greek/ correctly, 
to allow "Ω" and other Greek letters in PdfLaTeX, it is necessary to add


\usepackage{textalpha}

The fontenc package may map ASCII characters to Greek letters.


No need for any of it, just insert --- for an em dash and -- for an en
dash with numbers.


I do not see a real reason to prohibit Unicode "—" EM DASH character 
nowadays. Moreover, dashes and spaces around them depends on particular 
language. Likely it is not the case of Greek however. There are variety 
of dashes besides --- and --:


\cdash--- ”--- Cyrillic emdash in plain text.
\cdash--~ ”--~ Cyrillic emdash in compound names (as in
   Mendeleev”--~Klapeiron).
\cdash--* ”--* Cyrillic emdash for denoting direct speech.

As to LuaLaTeX, CMU (Computer Modern Unicode) fonts has better coverage 
of various characters than default Latin Modern fonts


\usepackage{fontspec}
\setmainfont{CMU Serif}
\setsansfont{CMU Sans Serif}
\setmonofont{CMU Typewriter Text}

I can say nothing concerning its quality in respect to printed documents 
in comparison to DejaVu or Noto.

Re: LaTex Unicode entry issues

[David]

On Sun, 2023-08-27 at 10:16 +0700, Max Nikulin wrote:
> On 26/08/2023 19:08, Haines Brown wrote:
> > \documentclass[12pt]{article} %
> > \usepackage[utf8]{inputenc} %
> > \usepackage[T1]{fontenc} %
> > \usepackage[greek,english]{babel} % to make Greek charactes
> > available
> 
> It seems, you are overestimating effect. You still need to provide 
> fontenc containing Greek characters. Unless you have real reasons to 
> avoid LuaTeX, I recommend you to use lualatex instead of pdflatex.
> 
> > \DeclareUnicodeCharacter{2014}{\dash} % to get m-dash
> 
> Do you really need it? Even without explicit declaration there is no 
> issue with pdflatex and U+2014 character
> 
> \begin{document}
> Test—character.
> \end{document}
> 
> Not to mention
> 
>  Test---ligature.

> On the other hand in response to
> 
> \begin{document}
> Test\dash{}test.
> \end{document}
> 
> I get
> 
> ! Undefined control sequence.
> l.7 Test\dash
>   {}test.
> ?
> 
> There is \textemdash command however. So you \DeclareUnicodeCharacter
> is 
> incorrect and almost certainly unnecessary.

No need for any of it, just insert --- for an em dash and -- for an en
dash with numbers.

> > If I paste an upper case Omega % Ω
> > into a LaTeX file and run pdflatex on it I am told the character is
> > not
> > set up for LaTeX. \$ albatross tells me it is available in the
> > DejaVu
> > Sans font which I have installed.
> 
> It is sour, but in general even with LuaTeX engine you have to 
> explicitly specify particular font. In the specific case of "Ω", the 
> character is available in lmodern (default font used by LuaTeX).
> Unlike 
> browsers or office software, TeX engines do not try hard to find at 
> least some font that can be used as a fallback for particular
> character.
> 
> 
 Cheers!
-- 
A Kiwi in Australia,
doing my bit toward raising the national standard.

Re: LaTex Unicode entry issues

[Max Nikulin]

On 26/08/2023 19:08, Haines Brown wrote:

\documentclass[12pt]{article} %
\usepackage[utf8]{inputenc} %
\usepackage[T1]{fontenc} %
\usepackage[greek,english]{babel} % to make Greek charactes available


It seems, you are overestimating effect. You still need to provide 
fontenc containing Greek characters. Unless you have real reasons to 
avoid LuaTeX, I recommend you to use lualatex instead of pdflatex.



\DeclareUnicodeCharacter{2014}{\dash} % to get m-dash


Do you really need it? Even without explicit declaration there is no 
issue with pdflatex and U+2014 character


\begin{document}
Test—character.
\end{document}

Not to mention

Test---ligature.

On the other hand in response to

\begin{document}
Test\dash{}test.
\end{document}

I get

! Undefined control sequence.
l.7 Test\dash
 {}test.
?

There is \textemdash command however. So you \DeclareUnicodeCharacter is 
incorrect and almost certainly unnecessary.



If I paste an upper case Omega % Ω
into a LaTeX file and run pdflatex on it I am told the character is not
set up for LaTeX. \$ albatross tells me it is available in the DejaVu
Sans font which I have installed.


It is sour, but in general even with LuaTeX engine you have to 
explicitly specify particular font. In the specific case of "Ω", the 
character is available in lmodern (default font used by LuaTeX). Unlike 
browsers or office software, TeX engines do not try hard to find at 
least some font that can be used as a fallback for particular character.

Re: LaTex Unicode entry issues

[Eduardo M KALINOWSKI]

On 26/08/2023 09:08, Haines Brown wrote:

The question is: if my system has access to a character in that it can
be pasted, why cannot LaTeX do so as well.


Because TeX dates from before Unicode was even being discussed, and does 
not use the libraries for handling Unicode that the other software in 
your system does.


That's not to say it has not been modified to add at least partial 
support for Unicode (utf8 is even the default encoding since a couple 
years), but it's not the same as something built from the start to 
handle Unicode.


On the other hand, luatex and xetex are evolutions of tex that have a 
much more modern and native Unicode support. Use them instead of pdf(la)tex.


--
Now I lay me down to sleep
I pray the double lock will keep;
May no brick through the window break,
And, no one rob me till I awake.

Eduardo M KALINOWSKI
edua...@kalinowski.com.br

Re: LaTex Unicode entry issues

[Haines Brown]

On Fri, Aug 25, 2023 at 09:53:23PM +0700, Max Nikulin wrote:
> On 25/08/2023 03:24, Haines Brown wrote:
> > Now it returns the error: "not set up for use with LaTeX." What does
> > this error imply?
> > 
> > This code works to produce an astrisk:
> > 
> >     \char"002A
> 
> A complete minimal example of LaTeX document may describe better what are
> you trying to achieve. 

\documentclass[12pt]{article} %
\usepackage[utf8]{inputenc} % 
\usepackage[T1]{fontenc} % 
\usepackage[greek,english]{babel} % to make Greek charactes available
\DeclareUnicodeCharacter{2014}{\dash} % to get m-dash

\begin{document}

To get m dash rather than "-" I do % \dash. 
Why does this produce the error: Undefined control sequence?

If I paste an upper case Omega % Ω 
into a LaTeX file and run pdflatex on it I am told the character is not
set up for LaTeX. \$ albatross tells me it is available in the DejaVu
Sans font which I have installed. 

If I add \verb|\usepackage[greek,english]{babel}| 
to preface and paste an upper case Omega, in the body I get error: 
Command \verb|\textOmega| unavailable in encoding T1.

A program I use requires the dagger symbol, †, which is code point 2020.
But % \symbol{"2020} 
produces fatal error. 

The code for E is U+0045. I try % 0045
and get error: Unicode character % ^^^ (U+001E) 
not set up for use with LaTeX. It turns out that the character   
\verb| ^ |  can't be used. I suspect the command deprecated because
clashes it its use in math mode.

The command to produce a Omega % \char"005B
produces garbage, not a µ. This character is in DejaVu Sans, but LaTeX
is not able to display it. 

The question is: if my system has access to a character in that it can
be pasted, why cannot LaTeX do so as well.

\end{document}
 

-- 

 Haines Brown 

Re: LaTex Unicode entry issues

[debian-user]

Charles Kroeger  wrote:
> I just have a really large list of UTF-8 characters and if I need one
> I copy it and zap it in. I suppose this is not cool but, chacun a son
> gout.
> 
> a fun site if you want to write someone in UTF-8 runes.
> 
> https://www.cl.cam.ac.uk/~mgk25/ucs/examples/UTF-8-demo.txt

Gah! A mindworm. My browser shows boxes instead of characters for the
runes, but that's not what's got me.

The second column of the Thai poems is not aligned in my browser :(

But it is in my terminal. But not in gedit or tea or LO. Even when I
set LO to use Hack, which is the font my terminal says it is using.

So now I'm deep in the rabbit holes. Why do fonts behave like that! !!

> ⅩⅩⅥ - Ⅷ - ⅯⅯⅩⅩⅢ

Re: LaTex Unicode entry issues

[Charles Kroeger]

I just have a really large list of UTF-8 characters and if I need one I
copy it and zap it in. I suppose this is not cool but, chacun a son gout.

a fun site if you want to write someone in UTF-8 runes.

https://www.cl.cam.ac.uk/~mgk25/ucs/examples/UTF-8-demo.txt

ⅩⅩⅥ - Ⅷ - ⅯⅯⅩⅩⅢ

-- 
 ☢ ➛ ☠ ➛ ♺

Re: LaTex Unicode entry issues

[Max Nikulin]

On 25/08/2023 03:24, Haines Brown wrote:

Now it returns the error: "not set up for use with LaTeX." What does
this error imply?

This code works to produce an astrisk:

\char"002A


A complete minimal example of LaTeX document may describe better what 
are you trying to achieve. I believed that a usual issue is to allow 
unicode characters typed using compose key: α → ∞. LuaLaTeX should work 
with Unicode better than PdfLaTeX, however fonts must be explicitly 
configured. Fortunately it is easier to use e.g. truetype fonts.

Re: LaTeX Unicode entry issues

[Michel Verdier]

On 2023-08-24, Haines Brown wrote:

> I'm necessarily  working with a pdfLaTeX document.

You mean LaTeX document compiled with pdflatex ?

> My TexLive runs in emacs and automatically changes " to ``. This makes 
> it annoying to enter Unicode, for I have to paste it from the 
> terminal. Is there an easy way around this?

In LaTeX mode double-type " to get the character

Re: LaTex Unicode entry issues

[tomas]

On Fri, Aug 25, 2023 at 06:23:00AM +0200, to...@tuxteam.de wrote:

[...]

> Here [1] [...]

Gah. The ref:

[1] 
https://tex.stackexchange.com/questions/377613/solve-unicode-char-is-not-set-up-for-use-with-latex-without-special-handling-o

-- 
t


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Re: LaTex Unicode entry issues

[tomas]

On Thu, Aug 24, 2023 at 04:24:06PM -0400, Haines Brown wrote:
> I'm necessarily  working with a pdfLaTeX document.
> 
> I seem to recall from long ago that I could enter Unicode  
> in this way:
> 
>   002B
> 
> Now it returns the error: "not set up for use with LaTeX." What does 
> this error imply?
> 
> This code works to produce an astrisk: 
> 
>   \char"002A
> 
> but \char"20AE fails although the character ₮ is accessible in my 
> font. The error I get is "Bad character code (8366)...  character 
> number must be between 0 and 255. Does "character number refer to 
> 002A? If so why does this sequence of characters not fall between 0 
> and 255?
> 
> My TexLive runs in emacs and automatically changes " to ``. This makes 
> it annoying to enter Unicode, for I have to paste it from the 
> terminal. Is there an easy way around this?

The short answer: use a Unicode capable TeX/LaTeX engine (LuaTex/LuaLaTeX
is said to be the currently most complete, perhaps also XeTeX). Enter
the characters as Unicode (most probably UTF-8 encoded).

Here [1] is a longer answer, which explains that the "classical" TeX input
engine (and PDFLaTeX is in that category) is not quite up to the task
of "doing" full Unicode. 

I'd go with LuaLaTex. And stop entering funny things like \char"
and use straight UTF-8 instead.

Cheers
-- 
t


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Description: PGP signature

Re: LaTex Unicode entry issues

[David]

On Thu, 2023-08-24 at 16:24 -0400, Haines Brown wrote:
> I'm necessarily  working with a pdfLaTeX document.
> 
> I seem to recall from long ago that I could enter Unicode  
> in this way:
> 
>   002B
> 
> Now it returns the error: "not set up for use with LaTeX." What does 
> this error imply?
> 
> This code works to produce an astrisk: 
> 
> \char"002A
> 
> but \char"20AE fails although the character ₮ is accessible in my 
> font. The error I get is "Bad character code (8366)...  character 
> number must be between 0 and 255. Does "character number refer to 
> 002A? If so why does this sequence of characters not fall between 0 
> and 255?
> 
> My TexLive runs in emacs and automatically changes " to ``. This
> makes 
> it annoying to enter Unicode, for I have to paste it from the 
> terminal. Is there an easy way around this?

I just use TexMaker - occasionally Texstudio - with unicode enabled in
the editor settings.
Every now and again I will get a bad character reference, but that is
always because of the lack of that character or character size being
supplied by the font foundry concerned.
Not anything to do with the editor or TexLive.
Cheers!

-- 
A Kiwi in Australia,
doing my bit toward raising the national standard.

LaTex Unicode entry issues

[Haines Brown]

I'm necessarily  working with a pdfLaTeX document.

I seem to recall from long ago that I could enter Unicode  
in this way:

  002B

Now it returns the error: "not set up for use with LaTeX." What does 
this error imply?

This code works to produce an astrisk: 

\char"002A

but \char"20AE fails although the character ₮ is accessible in my 
font. The error I get is "Bad character code (8366)...  character 
number must be between 0 and 255. Does "character number refer to 
002A? If so why does this sequence of characters not fall between 0 
and 255?

My TexLive runs in emacs and automatically changes " to ``. This makes 
it annoying to enter Unicode, for I have to paste it from the 
terminal. Is there an easy way around this?

-- 

 Haines Brown 

Re: Chemfig Latex compile program

[lina]

Hi Jerome,
Hi Curt,

Thanks for the input, I changed the

\setdoublesep{0.2 em}  % 'Bond Spacing'
\setatomsep{1.45 em}% 'Fixed Length'
\setbondoffset{0.1 em} % 'Margin Width'
\newcommand{\bondwidth}{0.08 em} % 'Line Width'
\setbondstyle{line width = \bondwidth}
\setcrambond{2pt}{}{}

to
\setchemfig{bond style={line width=0.08 em,red!70}}
\setchemfig{chemfig style=red}
\setchemfig{double bond sep = 0.2 em, atom sep = 1.45 em, bond offset = 0.1
em, cram width=2pt}

It gets closer to what I want,

Thanks again, lina


On Fri, Oct 8, 2021 at 5:38 PM Curt  wrote:

> On 2021-10-08, lina  wrote:
> >
> > *l.24 \setdoublesep  {0.2 em}  % 'Bond Spacing'*
> >
> >
>
> I'm reading that the '\setdoublesep' macro is obsolete and has been
> replaced by '\setchemfig{}'. Maybe this has something to do with the
> error being thrown.
>
>
>
> https://ctan.org/ctan-ann/id/mailman.2235.1520625403.5100.ctan-...@ctan.org?lang=en
>
> http://tug.ctan.org/macros/generic/chemfig/chemfig-en.pdf
>
>

Re: Chemfig Latex compile program

[Curt]

On 2021-10-08, lina  wrote:
>
> *l.24 \setdoublesep  {0.2 em}  % 'Bond Spacing'*
>
>

I'm reading that the '\setdoublesep' macro is obsolete and has been
replaced by '\setchemfig{}'. Maybe this has something to do with the
error being thrown.


https://ctan.org/ctan-ann/id/mailman.2235.1520625403.5100.ctan-...@ctan.org?lang=en

http://tug.ctan.org/macros/generic/chemfig/chemfig-en.pdf

Re: Chemfig Latex compile program

[Jerome BENOIT]

Hello Lina, can you provide a more minimal sample that reproduce the error ?
Best wishes,
Jerome

On 08/10/2021 15:59, lina wrote:

Hi,

When I updated the system, the following .tex code does not work, it shows the 
error likes this:

(/usr/share/texlive/texmf-dist/tex/latex/chemformula/chemformula.sty
(/usr/share/texlive/texmf-dist/tex/latex/l3packages/xfrac/xfrac.sty
(/usr/share/texlive/texmf-dist/tex/latex/base/textcomp.sty)
(/usr/share/texlive/texmf-dist/tex/latex/l3packages/xtemplate/xtemplate.sty))
(/usr/share/texlive/texmf-dist/tex/latex/units/nicefrac.sty
(/usr/share/texlive/texmf-dist/tex/latex/base/ifthen.sty)))
! Undefined control sequence.
*l.24 \setdoublesep
                   {0.2 em}  % 'Bond Spacing'*


\NeedsTeXFormat{LaTeX2e}[1997/12/01]
\documentclass[
     journal=jacsat,
     manuscript=article
     ]{achemso}

\usepackage[version=3]{mhchem}
\usepackage{wrapfig}
\usepackage{subfig}
\usepackage{graphicx}
\usepackage{threeparttable}
\usepackage{longtable,booktabs}
\usepackage[table, svgnames, dvipsnames]{xcolor}
\usepackage[first=0,last=9]{lcg}


\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{chemfig,chemmacros}
%\chemsetup[chemformula]{format=\sffamily}
\usepackage{chemformula}
\renewcommand*\printatom[1]{\ensuremath{\mathsf{#1}}}

\setdoublesep{0.2 em}  % 'Bond Spacing'
\setatomsep{1.45 em}    % 'Fixed Length'
\setbondoffset{0.1 em} % 'Margin Width'
\newcommand{\bondwidth}{0.08 em} % 'Line Width'
\setbondstyle{line width = \bondwidth}
\setcrambond{2pt}{}{}

\usetikzlibrary{decorations}
\pgfdeclaredecoration{ddbond}{initial}{
   \state{initial}[width=4pt]{
     \pgfpathlineto{\pgfpoint{4pt}{0pt}}
     %\pgfpathmoveto{\pgfpoint{2pt}{2pt}}
     \pgfpathmoveto{\pgfpoint{1pt}{2pt}}
     \pgfpathlineto{\pgfpoint{2pt}{2pt}}
    \pgfpathmoveto{\pgfpoint{3pt}{2pt}}
     \pgfpathlineto{\pgfpoint{4pt}{2pt}}
     \pgfpathmoveto{\pgfpoint{4pt}{0pt}}
   }
   \state{final}{
     \pgfpathlineto{\pgfpointdecoratedpathlast}
   }
}


\begin{document}

\end{document}

Chemfig Latex compile program

[lina]

Hi,

When I updated the system, the following .tex code does not work, it shows
the error likes this:

(/usr/share/texlive/texmf-dist/tex/latex/chemformula/chemformula.sty
(/usr/share/texlive/texmf-dist/tex/latex/l3packages/xfrac/xfrac.sty
(/usr/share/texlive/texmf-dist/tex/latex/base/textcomp.sty)
(/usr/share/texlive/texmf-dist/tex/latex/l3packages/xtemplate/xtemplate.sty))
(/usr/share/texlive/texmf-dist/tex/latex/units/nicefrac.sty
(/usr/share/texlive/texmf-dist/tex/latex/base/ifthen.sty)))
! Undefined control sequence.

*l.24 \setdoublesep  {0.2 em}  % 'Bond Spacing'*


\NeedsTeXFormat{LaTeX2e}[1997/12/01]
\documentclass[
journal=jacsat,
manuscript=article
]{achemso}

\usepackage[version=3]{mhchem}
\usepackage{wrapfig}
\usepackage{subfig}
\usepackage{graphicx}
\usepackage{threeparttable}
\usepackage{longtable,booktabs}
\usepackage[table, svgnames, dvipsnames]{xcolor}
\usepackage[first=0,last=9]{lcg}


\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{chemfig,chemmacros}
%\chemsetup[chemformula]{format=\sffamily}
\usepackage{chemformula}
\renewcommand*\printatom[1]{\ensuremath{\mathsf{#1}}}

\setdoublesep{0.2 em}  % 'Bond Spacing'
\setatomsep{1.45 em}% 'Fixed Length'
\setbondoffset{0.1 em} % 'Margin Width'
\newcommand{\bondwidth}{0.08 em} % 'Line Width'
\setbondstyle{line width = \bondwidth}
\setcrambond{2pt}{}{}

\usetikzlibrary{decorations}
\pgfdeclaredecoration{ddbond}{initial}{
  \state{initial}[width=4pt]{
\pgfpathlineto{\pgfpoint{4pt}{0pt}}
%\pgfpathmoveto{\pgfpoint{2pt}{2pt}}
\pgfpathmoveto{\pgfpoint{1pt}{2pt}}
\pgfpathlineto{\pgfpoint{2pt}{2pt}}
   \pgfpathmoveto{\pgfpoint{3pt}{2pt}}
\pgfpathlineto{\pgfpoint{4pt}{2pt}}
\pgfpathmoveto{\pgfpoint{4pt}{0pt}}
  }
  \state{final}{
\pgfpathlineto{\pgfpointdecoratedpathlast}
  }
}


\begin{document}

\end{document}

Re: LaTeX - Newer REVTEX on Debian ?

[Jerome BENOIT]

Hello,

my guess was that the bbl must be updated. Namely,
compose with apsrev4-2.bst (or one among the others).
I would check which one is actually used in the aux or blg file,
and I would check which one is actually pickup with kpsewhich(1).
For instance, you can try from a terminal:

kpsewhich -progname bibtex apsrev4-2.bst

You can also try first to compose (with latexmk for example) the examples
provided by REVTeX in order to check your installation.

hth,
Jerome



On 04/07/2021 06:34, Robbi Nespu wrote:

I not sure how to update bst. Could you show me how?

Re: LaTeX - Newer REVTEX on Debian ?

[Robbi Nespu]

I not sure how to update bst. Could you show me how?

--
Robbi Nespu 
D311 B5FF EEE6 0BE8 9C91 FA9E 0C81 FA30 3B3A 80BA
https://robbinespu.gitlab.io | https://mstdn.social/@robbinespu