GISP Remote Sensing and Image Analysis 2

Question 1

Which classification approach assigns each pixel to a land cover class based purely on spectral statistics without using any training samples?

Accepted Answer

Unsupervised classification

Answer

Unsupervised classification algorithms like ISODATA and K-means group pixels into spectral clusters automatically without analyst-provided training data.

Question 2

What does the term 'geometric correction' in image processing address?

Accepted Answer

Correcting distortions caused by sensor tilt, Earth curvature, and terrain relief

Answer

Geometric correction involves transforming an image to match a map projection by correcting for sensor geometry, platform motion, Earth rotation, and topographic displacement.

Question 3

LiDAR point clouds classified as 'ground returns' are primarily used to generate which type of surface model?

Accepted Answer

Digital Terrain Model (DTM)

Answer

Ground-classified LiDAR returns represent bare-earth elevation and are interpolated to create a Digital Terrain Model that excludes vegetation and structures.

Question 4

In image classification accuracy assessment, what does the producer's accuracy measure?

Accepted Answer

The probability that a reference site is correctly classified on the map

Answer

Producer's accuracy (recall) measures how well reference sites of a given class are identified correctly on the classified map, indicating errors of omission.

Question 5

What is the purpose of pan-sharpening in remote sensing image processing?

Accepted Answer

Merging high-resolution panchromatic data with lower-resolution multispectral data

Answer

Pan-sharpening fuses a high spatial resolution panchromatic band with coarser multispectral bands to produce a color image at the higher spatial resolution.

GISP - Geographic Information Systems Professional Practice Test

GISP - Geographic Information Systems Professional Practice Test

GISP Remote Sensing and Image Analysis 2