Deck 4: Raster Data Model

Question 1

Which data structure stores the cell values by row and by group?

A) none of these is correct
B) run length code
C) cell by cell
D) quad tree

Answer 1

run length code

Question 2

The latest Landsat images are from:

A) Landsat 7
B) Landsat 10
C) Landsat 9
D) Landsat 8

Answer 2

Landsat 8

Question 3

Use a diagram to explain regional quadtree as a method for storing raster data.

Answer 3

No Answer

Question 4

A raster with a larger cell size has a higher spatial resolution than a raster with a smaller cell size.

Question 5

A land cover raster is most likely a(n) _________ raster:

A) integer
B) floating point

Question 6

Explain run length code as a method for storing raster data.

Question 7

Explain the advantages and disadvantages of the raster data model vs. the vector data model.

Question 8

Explain the difference between lossless and lossy compression methods, and name one example image format for each method.

Question 9

Briefly explain passive and active satellite systems.

Question 10

If a raster has the cell resolution of 30 meters, then a cell in the raster measures ______ on the ground:

A) none of these is correct
B) 900 square meters
C) 600 square meters
D) 300 square meters

Question 11

Panchromatic satellite images from GeoEye-1 and WorldView-4 have sub-meter spatial resolutions.

Question 12

Which of the following techniques can be used to generate DEMs?

A) All of these are correct
B) Only Optical sensors and LiDAR
C) Optical sensors
D) LiDAR
E) InSAR

Question 13

Explain panchromatic and multispectral satellite images.

Question 14

What is a digital raster graphic (DRG)?

Question 15

What is a georeferenced raster?

Question 16

You are given the following information on a 1 arc-second (30-meter) DEM:
UTM coordinates in meters at the lower-left corner: 560635, 4816399
UTM coordinates in meters at the upper-right corner: 570595, 4830380
How many rows does the DEM have? How many columns does the DEM have? And, what are the UTM coordinates at the center of the (row 1, column 1) cell?

Question 17

DEMs can be created from satellite images.

Question 18

A 16-bit raster can store a wider range of values than an 8-bit raster.

Question 19

The origin of a raster is at the ______corner of the raster:

A) upper right
B) upper left
C) lower right
D) lower left

Question 20

What is a digital orthophoto quad (DOQ)?

Question 21

A higher cell depth (e.g., 16-bit) means that the cell can store more information than a lower cell depth (e.g., 8-bit).

Question 22

A wavelet transform can perform either lossless or lossy compression.

Question 23

DEMs generated from LiDAR can represent different height levels.

Question 24

The process of converting a raster to a polygon feature class is called:

A) vectorization
B) rasterization

Question 25

Define "vectorization" and "rasterization."

Question 26

When a polygon shapefile is converted into a raster, an attribute from the shapefile's attribute table must be chosen for the cell value of the raster.

Question 27

Which of the following is an example of a multiband raster?

A) A vegetation raster
B) An elevation raster
C) All of these are correct
D) A satellite image

Question 28

Which data structure stores raster data as a matrix and writes the cell values into a file by row and column?

A) run length code
B) none of these is correct
C) cell by cell
D) quad tree

Question 29

How are spatial features of points, lines, and polygons represented in the raster data model?

Question 30

Vectorization refers to the process of converting from _____ data to _____ data:

A) raster, raster
B) vector, vector
C) vector, raster
D) raster, vector

Question 31

The Sentinel missions of the European Space Agency offer both active and passive satellite data.