Rendering images and drawing annotations

[mdylan2]

Is there a way to plot images, and make annotations on top of them (eg: drawing bounding boxes)?

Imshow example: https://www.geeksforgeeks.org/matplotlib-pyplot-imshow-in-python/

[Fil]

Yes! Combine a raster mark and a rect mark.

[mdylan2]

How would this work for RGB images? Is it one raster per channel?

Never mind, figured it out, I think you can just multiply the length of the data in the grid that you put in

[mdylan2]

This makes sense! What about free-form annotation?

I'm working with images of bacterial cells, which are oddly shaped - how would you handle event driven free-form annotation?

[Fil]

To follow the pointer and clicks, you can use https://observablehq.com/@fil/pointer-events-svg

However you'll need a system to record the shapes. You could save them to localStorage for example, or allow the user to download them as a json file.

You can then display the shapes with Plot.geo