What happens to uploaded or rectified images. Are they stored somewhere?

Images and geometric data are deleted from our servers immediately after processing. The tool uses standard SSL certificate for security. We do not track your actions, geolocation, or times of usage.

I am thinking of using this tool for my investigations, or I would like to include this tool as a part of a methodology for a legal court filing or report. What should I know before using it?

You should know that none of the images you upload or rectified are stored after processing. It is important to know that neither pixels' colors are distorted nor new pixel values are introduced; all color data in rectified images preserve their original states, so you can reliably use it as a part of methodology for legal purposes. However, the algorithm tries to preserve the aspect ratio of original images and, therefore, stretches out objects or sometimes blacks out sections for which no pixels exist in the original image. Therefore, you can't rely on estimating sizes of objects through this tool — it is not its original goal.

What does it do?

Rectification is a transformation process that projects an original image onto a new plane to form a geometrically perspective-corrected image. It is mostly used in remote sensing / geospatial industries, but becomes very handy for OSINT purposes and evidence analysis.

What's the right order of choosing the area of interest?

Ordering of points matters as it would rotate the rectified image accordingly. First, make sure you are choosing in clock-wise / counter-clockwise order. The recommended path is upper left, lower left, lower right, upper right.

Is this tool open-source?

Yes. You can find code on the Github here.