MRES Exercise #6 Rectifying and Referencing Images Using MATLAB

This exercise is intended to help students to understand how rectify and reference images using MATLAB. Possible applications are outcrop images (with a scale), aerial and satellite images (with reference points).

Take a picture of a rectangular arrangement of objects, such as the exhibition of plates of rocks in the department building.
Rectify and reference the image onto an orthogonal centimeter grid.
Determine the size of the rock plates from the image.

Solution

Take the image with a camera and import the image into MATLAB.
Measure the width and the height of the rectangular arrangement of objects. In our example, the display of rock plates is 656 cm wide and 131 cm high.
Pick pixel xy coordinates from the image using the MATLAB function ginput.
Use the functions fitgeotrans and imwarp to rectify and reference the image.
Use the data cursor of the Figure Window to determine the size of the rock plates.

Download the MATLAB script and example image.

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Trauth, M.H. (2025) MATLAB Recipes for Earth Sciences – Sixth Edition. Springer International Publishing, 550 p., ISBN 978-3-031-57948-6. (MRES)
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Trauth, M.H. (2022) MATLAB®-Rezepte für die Geowissenschaften, 1. deutschsprachige Auflage, basierend auf der 5. englischsprachigen Auflage. Springer Spektrum, 544 p., ISBN 978-3-662-64356-3. (MRG)
Trauth, M.H. (2024) Python Recipes for Earth Sciences – Second Edition. Springer International Publishing, 450 p., Supplementary Electronic Material, ISBN 978-3-031-56905-0. (PRES)
Trauth, M.H. (2024) Python-Rezepte für die Geowissenschaften, 1. deutschsprachige Auflage, basierend auf der 1. englischsprachigen Auflage. Springer Spektrum, 492 p., ISBN 978-3662681176. (PRG)