Geometric image tagging

November 3, 2015 7:57 PM

I have a bunch of images and I want to tag various objects in them by drawing simple shapes around the objects (rectangles, circles, etc). Is there some software I can use to easily do this?

Ideally it would give me CSV or other parseable output with parameters like the center and orientation of each shape tied with the filename. (To clarify, I'm doing the drawing of the shapes, not any automated recognition).

posted by dilaudid to Technology (1 answer total)

I think Inkscape could work for you. I am assuming you intend to display each image on the screen and then draw shapes on top of it, and you wish to save these shapes separately from the original image. The workflow with Inkscape would look like this.

Having Inkscape open, drag the image you want to tag onto the canvas and import it.
Place it in its own layer and make another layer for drawing the shapes.
Draw the shapes.
Delete the layer with the image and export the drawing to an SVG file.
Parse the SVG file using some suitable XML parser.

I experimented with this and drew three ellipses on top of a cat picture. I then exported just the ellipses to an SVG file. I can easily find the ellipses in the resulting file even using a text editor, and while there is some metadata about the SVG file and Inkscape in there, I would not say the resulting file is bloated or messy.

Inkscape is free software. The SVG file format documentation is easily located on the web.
posted by primal at 2:33 AM on November 4, 2015