standalone library for OpenOffice formula renderer? - math

Question

Is there a standalone library of OpenOffice's formula renderer? I'm looking for something that can take plain text (e.g. E = mc^2) in the same syntax as used by OpenOffice, and convert to png or pdf fragments.
(note: I don't need the WYSIWYG editor, just the renderer. Basically I would like to work in OpenOffice to interactively edit my formulas, and then copy the source text for use in other contexts w/o needing OpenOffice to render them.)

Answer 1

I'm using unoconv to convert OpenOffice/LibreOffice document to PDF.
However, first I had to create some input document with a formula.
Unfortunately, it is not possible to use just the formula editor to create ODF file because the output PDF file would contain weird headers and footers.
Therefore, I created a simple text document (in Writer) and embedded the formula as a single object (aligned as a character). I saved the ODT file, unzipped it (since ODT is just a ZIP) and edited the content. Then, I identified what files can be deleted and formatted the remaining files to get a minimal example.
In my example, the formula itself is located in Formula/content.xml. It should be easy to change just the code within the <annotation>...</annotation> tags in an automated way.
Finally, I zipped the directory and produced a new ODT file.
Then, using unoconv and pdfcrop, I produced a nice formula as PDF.
# this trick prevents zip from creating an additional directory
cd formula.odt.unzipped
zip -r ../formula.odt .
cd ..
unoconv -f pdf formula.odt # ODT to PDF
pdfcrop formula.pdf # keep only the formula
# you can convert the PDF to bitmap as follows
convert -density 300x300 formula-crop.pdf formula.png
Content of the unzipped ODT directory:
Here is the minimal content of an ODT file formula.odt.
formula.odt.unzipped/Formula/content.xml
formula.odt.unzipped/META-INF/manifest.xml
formula.odt.unzipped/content.xml
File formula.odt.unzipped/Formula/content.xml contains:
<?xml version="1.0" encoding="UTF-8"?>
<math xmlns="http://www.w3.org/1998/Math/MathML" display="block">
<semantics>
<annotation encoding="StarMath 5.0">
f ( x ) = sum from { { i = 0 } } to { infinity } { {f^{(i)}(0)} over {i!} x^i}
</annotation>
</semantics>
</math>
File formula.odt.unzipped/content.xml contains:
<?xml version="1.0" encoding="UTF-8"?>
<office:document-content
xmlns:office="urn:oasis:names:tc:opendocument:xmlns:office:1.0"
xmlns:text="urn:oasis:names:tc:opendocument:xmlns:text:1.0"
xmlns:draw="urn:oasis:names:tc:opendocument:xmlns:drawing:1.0"
xmlns:xlink="http://www.w3.org/1999/xlink">
<office:body>
<office:text>
<text:p>
<draw:frame>
<draw:object xlink:href="./Formula"/>
</draw:frame>
</text:p>
</office:text>
</office:body>
</office:document-content>
File formula.odt.unzipped/META-INF/manifest.xml contains:
<?xml version="1.0" encoding="UTF-8"?>
<manifest:manifest xmlns:manifest="urn:oasis:names:tc:opendocument:xmlns:manifest:1.0" manifest:version="1.2">
<manifest:file-entry manifest:full-path="/" manifest:version="1.2" manifest:media-type="application/vnd.oasis.opendocument.text"/>
<manifest:file-entry manifest:full-path="content.xml" manifest:media-type="text/xml"/>
<manifest:file-entry manifest:full-path="Formula/content.xml" manifest:media-type="text/xml"/>
<manifest:file-entry manifest:full-path="Formula/" manifest:version="1.2" manifest:media-type="application/vnd.oasis.opendocument.formula"/>
</manifest:manifest>

Answer 2

There are several web services that run LaTeX for you and return an image. For instance, http://rogercortesi.com/eqn/