figure file format and export

[will-moore]

Currently, OMERO.figure files are stores as JSON files, in a format described at https://github.com/ome/omero-figure/blob/master/docs/figure_file_format.rst but we don't have a schema to define this.

To view a figure in any external application or web page, the figure must be exported to PDF or TIFF, using python code in the server-side script at https://github.com/ome/omero-figure/blob/master/omero_figure/scripts/omero/figure_scripts/Figure_To_Pdf.py

Current issues:

• Any external code that creates an OMERO.figure file (e.g. Jupyter notebook or OMERO.server script) can't easily produce an exported figure in PDF or TIFF format
• OMERO.figure itself needs a server-side python script to export to PDF/TIFF
• Can't embed an OMERO.figure file in another web page

One option worth exploring is to save figures as svg, along with necessary metadata (e.g. in desc tags) to allow opening again in OMERO.figure.

https://inkscape.org/learn/faq/#about-svg

cc @jburel

[joshmoore]

Saving as an SVG is certainly a very "standards-compliant" way of doing it. After seeing @mutterer's presentation, I also wonder if this wouldn't take us a step closer to being able to "embed" an OME-Zarr within the SVG. cc: @manzt