Get image of equation

Question

I would like to make .png images of equations. To achive that I use pdflatex + pdfcrop + convert. But it takes more than 3 seconds on my computer to process simple $$E=mc^2$$. But I will generate dozens of images and I would like to do it as fast as possible.

pdfcrop is really slow and now I am trying to fit equation into page to except crop from my cycle. I use this:

\documentclass[landscape]{report}
\usepackage{amsmath} 
\usepackage{graphicx}

\begin{document}
\thispagestyle{empty}

\begin{equation*}
\resizebox{1.0\linewidth}{!} 
{
    $ E = mc^2 $
}
\end{equation*}

\end{document}

pdflatex produces this:

So, it's a lot of blank space around the equation. Moreover, I would like to use latex instead of pdflatex because it's faster. But latex ignores resizebox environment. So, my questions are: Is it possible to

1) Make pdflatex scale equation to entire page?

2) Similar but using latex?

3) Or maybe there is another way to produce images of equations?

Latex is not really faster than pdflatex, remember it is the same executable. See the standalone class, it is build for stuff like this. Ive used it to make equation images for someone to use in InDesign — daleif, Sep 22 '18 at 06:25
@daleif can you please provide an example of generating image using standalone? — danielleontiev, Sep 22 '18 at 06:34
@danielleontiev: Generating image using standalone is addressed in TeX to image over command line. I think a lot of the time is taken in loading tex. This can be sped using a .fmt file as per Custom format file: How to automate the generation of the “precompiled preamble” whenever one of the files that are used there are changed and Ultrafast PDFLaTeX with precompiling. — Peter Grill, Sep 22 '18 at 07:01
Get rid of the resize box, and the thispagestyle, replace report by standalone — daleif, Sep 22 '18 at 09:09
But why are you doing this? To put in a word document or is it for other use? — Arne Timperman, Sep 22 '18 at 13:29
Using TeX4ht, you can generate PNG format file for all display equations — MadyYuvi, Feb 15 '24 at 07:21

score 1 · Accepted Answer · answered Sep 22 '18 at 12:26

I sometimes also need a picture of a LaTeX equation. For this, I use the following tex file equation.tex:

\documentclass{standalone}

\begin{document}
$\displaystyle  E = m\,c^2$
\end{document}

Since it uses the standalone class, no pdfcrop is required and the resulting PDF contains your equation only, and nothing else, no borders, nothing. In the same folder as the equation.tex I also have a Makefile as follows

.PHONY: all clean

equation.pdf: equation.tex
    pdflatex --interaction=nonstopmode equation.tex
    convert -background white -alpha remove -density 600 equation.pdf equation.png

clean:
    --@rm -rf *.aux *.log *.lof *.bak *.loa *.log *.lot *.bbl
    --@rm -rf *.blg *.dvi *.out *.brf *.thm *.toc *.idx *.ilg *.ind
    --@rm -rf *eps-converted-to.pdf *.gnuplot *.tps
    --@rm -rf *.nav *.snm *.vrb *.lol *.tmp *.synctex *.synctex.gz
    --@rm -rf *.xwm *.pdf

and if you run the make command inside this directory, it produces the PDF with the equation and converts it to PNG. Note that on Windows, you need to enter the full path to the convert tool, e.g.

c:\programs\ImageMagick-6.8.5\bin\convert -background white -alpha remove -density 600 equation.pdf equation.png

On my box, this PDF creation and the conversion to PDF runs pretty fast. I would say less than 1/2 sec, and not 3 sec.

The above shown mwe produces this png file:

score 0 · Answer 2 · answered Feb 15 '24 at 01:32

0

If you use TeXstudio, it has the function "preview selection". You can just select an equation and use the function.

answered Feb 15 '24 at 01:32

Vezen BU

121

Get image of equation

2 Answers2