On 3/21/20 12:26 PM, Graeme wrote:
On 3/18/20 3:19 PM, Graeme wrote:
I currently use Linux Mint 18.3. Recently I upgraded to LyX 2.3.4.2
using the PPA available at
http://ppa.launchpad.net/lyx-devel/release/ubuntu xenial main
Since this upgrade there have been problems with the display of EPS
and PDF graphics files in the main LyX editor window, and with the
export of files containing PNG and JPEG bitmap images.
These problems are not evident with LyX 2.3.4.3 on Windows 10, nor
were they present with LyX 2.3.3 on Linux Mint 18.3.
Specifically:
1. When including a graphic with either EPS or PDF format, the
graphic is not displayed in the main LyX editor window, but instead
there is an outline box with the EPS or PDF filename, and below it
the error message: Error converting to loadable format.
The graphic does appear correctly in a PDF file exported using
either ps2pdf or pdflatex.
2. When including a graphic with PNG or JPEG format, the graphic is
displayed correctly in the main LyX editor window, but when
attempting to export the LyX file to Postscript, PDF (using ps2pdf),
or even just plain LaTeX, an error pop-up window appears with the
title:
LyX: Cannot convert file
and the message: No information for converting png format files to
eps. Define a converter in the preferences or No information for
converting jpg format files to eps. Define a converter in the
preferences.
The PNG and JPEG graphics do appear correctly in a PDF file
exported using pdflatex, but attempting to export with ps2pdf fails.
When exporting the Progress Log window shows the following messages
for a graphic in PNG format:
python -tt "/usr/share/lyx/scripts/convertDefault.py" png
"/tmp/lyx_tmpdir.fGfmcihv6288/lyx_tmpbuf0/2_home_graeme_Documents_GraphicsTestCircle.png"
eps
"/tmp/lyx_tmpdir.fGfmcihv6288/lyx_tmpbuf0/2_home_graeme_Documents_GraphicsTestCircle.eps"
convert: not authorized
`eps:/tmp/lyx_tmpdir.fGfmcihv6288/lyx_tmpbuf0/2_home_graeme_Documents_GraphicsTestCircle.eps'
@ error/constitute.c/WriteImage/1028.
/usr/share/lyx/scripts/convertDefault.py ERROR
Execution of "convert" failed.support/Systemcall.cpp (276):
Systemcall: 'python -tt "/usr/share/lyx/scripts/convertDefault.py"
png
"/tmp/lyx_tmpdir.fGfmcihv6288/lyx_tmpbuf0/2_home_graeme_Documents_GraphicsTestCircle.png"
eps
"/tmp/lyx_tmpdir.fGfmcihv6288/lyx_tmpbuf0/2_home_graeme_Documents_GraphicsTestCircle.eps"'
finished with exit code 1
Error: Cannot convert file
I get similar messages for a graphic file in JPEG format.
My suspicion is that BOTH the problems above may be linked to the
use of ImageMagick within convertDefault.py, but I am puzzled by the
warning message
"convert: not authorized"
in the fragment above, suggesting it may be something to do with
file or folder permissions. However, this does not explain why
everything seemed to work OK with LyX 2.3.3 on Mint 18.3
On Mint 18.3 the system-wide installation of ImageMagick is:
ImageMagick 6.8.9-9 Q16 x86_64 2019-11-12
On Windows 10, the LyX2.3.4.3 installer comes bundled with a later
version:
ImageMagick 7.0.9-19 Q16 x86 2020-01-26
which explicitly lists built-in support for gslib and ps, but
ImageMagick 6 does not list these among its "Delegates".
I would welcome advice on how to fix these problems.
Graeme
Confirmed here (same OS and LyX version). Turns out it's a security
issue related to ImageMagick. See this post
<https://cromwell-intl.com/open-source/pdf-not-authorized.html> for
the gory details. If you're willing to take the risk (I am), you can
follow the suggestions in the post, but there may be a quicker way.
Wander over to /etc/Imagick-6 and list the directory. You should see
policy.xml and policy.xml.dpkg-old. They former is the higher
security/problematic policy file in force, and the .dpkg-old version
is the looser, less secure (but more LyX friendly) version. As root,
give the new one a new name or extension to keep it (or delete it if
you will) and move or copy the .dpkg-old version to policy.xml.
Worked for me.
Paul
Thanks, Paul, for your quick and helpful reply.
Unfortunately, in my Mint etc/ImageMagick-6 folder there was only
policy.xml with no .dpkg-old version with which to compare or replace it.
I followed the link you supplied, had a look at the documentation for
ImageMagick, and at the policy.xml file bundled with LyX for Windows,
but the syntax and terminology of policy.xml files remains rather
obscure to me.
Since it's the effect of these security policies on the behaviour of
ImageMagick with EPS (and PS) files that matters. I've made small
changes to the ImageMagick-6 version that allow the convert command to
operate as desired on EPS and PDF files.
The key code fragment in /etc/ImageMagick-6/policy.xml is in the
<policymap> section of the file:
<!-- disable ghostscript format types -->
<policy domain="coder" rights="none" pattern="PS" />
<policy domain="coder" rights="none" pattern="PS2" />
<policy domain="coder" rights="none" pattern="PS3" />
<policy domain="coder" rights="none" pattern="EPS" />
<policy domain="coder" rights="none" pattern="PDF" />
<policy domain="coder" rights="none" pattern="XPS" />
I modified two lines in this fragment as follows:
<policy domain="coder" rights="read|write" pattern="PS" />
<policy domain="coder" rights="read|write" pattern="EPS" />
1. Changing only the PS line allowed the LyX editor window correctly
to display included graphic files in EPS or PDF format, but
File/Export/PDF(ps2pdf) still failed with LyX files that included PNG
or JPEG graphics.
2. Changing only the EPS line resolved the problem of exporting files
with included PNG or JPEG graphics, but did not allow the LyX editor
window to display included graphic files in EPS or PDF format.
3. It wasn't necessary to change the PDF line. Not sure why.
4. It seems that changing both the PS and the EPS lines is sufficient
to resolve both problems, but I don't know whether this is the
necessary minimum. Is there a better, or safer, way of modifying the
file policy.xml?
Finally, I'm surprised that the problem has so far only been reported
for Linux Mint, prompting the following questions:
a) Does Mint have a much stricter security policy for ImageMagick than
Ubuntu or other Linux distributions?
b) None of the lines in the <policymap> fragment above appear in the
policy.xml for ImageMagick 7 that is bundled with LyX 2.3.4.3 in the
Windows installer. Was that policy.xml crafted specifically to work
with LyX, and to avoid the problems reported here?
Graeme
Graeme,
Interesting that you did not have the old version of the policy file.
FWIW, the old version I have lacks two of the six policy items you
listed (PS2 and PS3) and simply comments out, rather than modifying, the
other four.
To answer your first question, Mint gets Imagemagick and associated
files from the Canonical repositories. (The policy file is in the
imagemagick-common package.) Honestly, I have no idea where I got the
older version of the file. It does not appear to have been installed by
synaptic (or at least synaptic won't admit to having done so.) Possibly
it came along with something I installed from a PPA.
As to the Windows version, I really don't know, but perhaps the Windows
version of Imagemagick is less vulnerable to the security problems those
extra lines are designed to combat? (This would be the first time in my
experience that Windows was less vulnerable to anything, but there are
more things in the digital realm than in my philosophy.)
Paul
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