automeris-io / WebPlotDigitizer

Computer vision assisted tool to extract numerical data from plot images.
https://automeris.io
GNU Affero General Public License v3.0
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support colors digitization (heatmap, scatterplot) #41

Open kotliary opened 9 years ago

kotliary commented 9 years ago

Hello Ankit, It would be nice to get values represented by colors, for example, on a heatmap. I can imagine it's not strait-forward, but probably doable. It would require a proper grids from user (might be with an image rotation fix) and using a color key axis with multiple points pickup to fit the value-color function (or functions for each color channel). As an alternative (for example, if color key is not available) WebPlotDigitizer can return color values in a color space selected by user. Another example of this is a scatterplot where color of a dot represent some value. Love your tool. Yuri

ankitrohatgi commented 9 years ago

Hi Yuri,

Those are some great ideas!

A few months ago, I did some experiments where I was successful in writing a code that used the color key in a heatmap to get values (and the error associated with each point). Given enough time, I can implement it in WPD. Let's see when I get that kind of time.

I like your idea of using colors in the plot directly rather than always relying on some color key. I will think about this some more!

Cheers, Ankit