GEOM 30009: Imaging the Environment 

1. Image interpretation and electromagnetic radiation: 

The diagram below shows the spectral reflectance of three tree species in visible and near infrared wavelengths. Explain how these curves can be used to identify the three tree species in multispectral images? (10 points) 2. Human vision and image formation: Image resolution is a characteristic that defines the ability to resolve different objects or phenomena in an image. Explain the four types of resolution that characterize an imaging system. (10 points) 3. Imaging sensors: Different imaging sensors are suitable for different tasks and applications. Name four criteria that should be taken into account when selecting a suitable imaging sensor for a given task, and explain each of the criteria. (10 points) 4. Image processing: A useful image processing technique applied to multi-spectral images is pan sharpening. Explain the purpose of pan sharpening (5 points), and describe the steps involved in the process (5 points). 5. Information extraction: Image segmentation is a process that enables image analysis on object level. Describe the two types of segmentation errors that usually occur in a segmented image (10 points). 6. Image classification: The accuracy of image classification is often evaluated by constructing a confusion matrix. What do the diagonal elements of a confusion matrix represent? (5 points) What do the off-diagonal elements represent? (5 points) 7. Image rectification: The image rectification process consists of a transformation and a resampling step. Describe the steps involved in resampling (inverse mapping) by interpolation. (10 points) GEOM 30009 Imaging the Environment Page 4 of 4 8. 9. 10. Orthorectification: What is relief displacement? (4 points) Describe a simple orthorectification process to correct for relief displacement. (6 points) 2D measurement in images: Which of the following processes should be applied to an image before it can be used for making reliable 2D measurements? Explain your answer. (10 points)  Band ratios  Orthorectification  Image segmentation  No processing is needed. 3D measurement in images: A simple method for stereoscopic viewing is by using anaglyphic display and glasses. Describe the anaglyphic stereoscopic viewing and discuss its pros and cons. (10 points) End of Exam GEOM 30009 Imaging the Environment