latexmlpost ends abruptly when gif or pdf images are used

[goska]

Do you know what may cause latexmlpost conversion to HTML fail abruptly when gif or pdf images are used as source images in Figure environment? The process ends abruptly with message: "Warning:perl:warn Exception 410: Unrecognized attribute (option) at /usr/local/share/perl5/LaTeXML/Util/Image.pm line 483

• post-processing Graphics composite-figures-test2.html 28 to process." (composite-figures-test2.html is the destination HTML file). latexmlpost log generated for this conversion is empty.

Conversion works with jpg and png images.

I am testing conversion with LaTeXML 0.8.7 of test files, which worked OK with previous versions of LaTeXML, including 0.8.6. I am working with LaTeXML installed for me by server admins on a new server. Conversion with LaTeXML 0.8.2 running on the old server (to be decommissioned) of the same files works. Conversion with LaTeXML 0.8.5 and 0.8.6 on my personal MacBook worked too. I am using two-step conversion LaTeX -> XML -> HTML using latexmlpost option --format=html5.

[dginev]

For simple png and jpg images latexml has the option to just pass them along untouched in the final HTML (as with gif and svg), but for PDF there needs to be a dedicated conversion step to a web image format, which typically happens via imagemagick.

I quickly experimented with:

\documentclass{article}
\usepackage{graphicx}
\begin{document}

\includegraphics[width=0.5\textwidth]{test.gif}

\includegraphics[width=0.5\textwidth]{test.pdf}

\end{document}

On a gif and pdf image that I grabbed from an image search, and things look operational with latexml 0.8.7, using the imagemagick dependencies described in the get latexml page.

Can you still reproduce the problem via such test file @goska ? Would you be open to sharing the full log of post-processing?

In addition, here is a report of the underlying imagemagick installation on my machine using convert --version:

$ convert --version
Version: ImageMagick 6.9.11-60 Q16 x86_64 2021-01-25 https://imagemagick.org
Copyright: (C) 1999-2021 ImageMagick Studio LLC
License: https://imagemagick.org/script/license.php
Features: Cipher DPC Modules OpenMP(4.5) 
Delegates (built-in): bzlib djvu fftw fontconfig freetype heic jbig jng jp2 jpeg lcms lqr ltdl lzma openexr pangocairo png tiff webp wmf x xml zlib

Does that look comparable to your setup?

[dginev]

installed for me by server admins on a new server

I spotted this part of your report too late. There is a very relevant imagemagick security issue on older servers, which led them to completely disable PDF support.

See the full details here: #1216

I even have the workaround embedded in the recent Dockerfile I made for the ar5iv-style conversion. You can reuse them from: https://github.com/dginev/ar5ivist/blob/main/Dockerfile#L74-L82

Let me know if that happened to be the issue on that particular machine.

[goska]

Thank you, @dginev. My conversion works on old server, but it fails on the new server with up-to-date OS (I think it's Red Hat, I'll check). It also works on a Mac with a recent OS under LaTeXML 0.8.6. I'll test conversion with the simple file you have suggested, and check what response I get to convert command.

[goska]

I have tested conversion of the simple document, based on your test document above with LaTeXML 0.8.7 (the new server), and it failed with the same error: Warning:perl:warn Exception 410: Unrecognized attribute (option) at /usr/local/share/perl5/LaTeXML/Util/Image.pm line 483

• post-processing Graphics figures-test-basic.html 2 to process I have also executed convert --version command on the old server (where conversion of pdf and gif images works) and the new server (where it fails). ImageMagick is installed on both servers, but the versions are different: 6.7.2 and 6.9.12 respectively. On the new server the command also yielded information about "built-in delegates", which include jpg and png, but not pdf and gif. I guess, this is the cause of my problem. I am not concerned about not being able to convert figures using gif images, because they don't work with pdflatex, which I use for generating PDF versions of documents. No longer being able to convert documents using pdf images is a problem. @dginev, thank you for your help.

[dginev]

@goska sounds like checking for the security policy is the next obvious thing to do. On an Ubuntu machine that is:

$ cat /etc/ImageMagick-6/policy.xml |grep "PDF"

You may see lines such as:

<policy domain="module" rights="none" pattern="{PS,PDF,XPS}" />
<policy domain="coder" rights="none" pattern="PDF" />

which then needs to be disabled so that PDF processing is allowed, either by removing that line or commenting it out:

<!-- <policy domain="module" rights="none" pattern="{PS,PDF,XPS}" /> -->
<!-- <policy domain="coder" rights="none" pattern="PDF" /> -->

Naturaly, you will need root access to modify that file. If that solves the problem, then this issue will turn out to be a duplicate of #1216 .

[goska]

I'll ask people managing the server if changing security policy is acceptable.

[xworld21]

Partially off-topic: I'd recommend converting PDF outside of latexmlpost, using e.g. dvisvgm. latexmlpost should be smart enough to detect files with the same name but different extension, and prefer SVG over PDF. Or at least, I believe it works like that at the moment. This is assuming you want to convert PDF to SVG, which is normally the best way to go unless you have specific compatibility issues.

On top of the security holes, ImageMagick does a terrible job at converting vector graphics to vector graphics: it rasterises the image, then traces it, with very poor results. It should be absolutely avoided for any PDF/EPS -> SVG conversion.

[goska]

Thanks for advice, @xworld21. @dginev, the list of "delegates" installed on my new server is the same as yours, so the issues with conversion of pdf images are most likely due to the security policy settings. I am not sure what may be causing problems with conversion of gif images.