Processing Raster Data Using ArcGIS Pro

Question 1

Raster data processing can be defined as a set of what?

Answer 1

transformation steps performed on raster data to extract meaningful information.

Question 2

What can be as simple as altering the visual appearance of the raster data, transforming the coordinate system, or creating a new dataset, or it can involve a complex processing algorithm, such as segmentation and multivariate classifications.

Answer 2

Raster data processing

Question 3

Geometric function: correcting a raster using orthorectification, what does it do?

Answer 3

Corrects the image for topographic distortion pixel by pixel. The result is that every pixel appears to be viewed from directly above.

Question 4

What are lightweight operations that do not change the original source data. They are used everywhere on the ArcGIS platform and can be configured to be used with image services, applied to images within ArcGIS Desktop, and applied to a collection of images that are being managed using a mosaic dataset.

Answer 4

Raster functions

Question 5

Where can you access raster functions in ArcGIS Pro?

Answer 5

Raster Functions pane

Question 6

Raster Processing considerations: Possible questions to consider.

Answer 6

Does the dataset adequately cover your study area?

Will you write the output to a new dataset?

Are you working with only a subset of the dataset available?

What is the most effective workflow to follow to achieve your goals?

Question 7

Identify appropriate functions to use for each of the following scenarios: You work for a water planning and management department and have acquired a set of temporal multispectral images. You would like to monitor drought to mitigate impacts on agriculture in your region.

Answer 7

Using the NDVI function is appropriate because it quantifies the spatial variability of vegetation condition.

Question 8

Identify appropriate functions to use for each of the following scenarios: You would like to map a mountainous terrain where you separate areas that are flat or have few features from the areas with steep slopes.

Answer 8

Using the Shaded Relief function can emphasize terrain structure and show variations in elevations.

Question 9

Identify appropriate functions to use for each of the following scenarios: You have obtained GeoEye-1 imagery with clouds in some areas. You want to exclude the areas with clouds.

Answer 9

Using the Clip function allows you to exclude clouds from an image.

Question 10

Identify appropriate functions to use for each of the following scenarios: You have acquired a set of Landsat 8 images. You would like to adjust their brightness to a common illumination condition so that there is less variation between scenes.

Answer 10

Using the Apparent Reflectance function adjusts image pixel values based on the sensor metadata and the sensor’s gains and biases.

Question 11

Raster functions can also be what together to create complex processing chains. By chaining together a series of raster functions, users can perform multiple or sequential on-the-fly processing. Examples include converting units between datasets, finding anomalies, and calculating slope. All of these tasks can be done without changing the original data or creating derivative or intermediate products. Like singular raster functions, the output of a raster function chain can be applied to a raster dataset, mosaic dataset items, mosaic dataset, or an image service.

Answer 11

chained

By chaining together a series of raster functions, users can perform multiple or sequential on-the-fly processing. Examples include converting units between datasets, finding anomalies, and calculating slope. All of these tasks can be done without changing the original data or creating derivative or intermediate products. Like singular raster functions, the output of a raster function chain can be applied to a raster dataset, mosaic dataset items, mosaic dataset, or an image service.

Question 12

What is a chain of raster functions with variables and with no datasets defined.

Answer 12

A raster function template

You can apply these raster function templates to rasters, mosaic datasets, and image services. A raster function template makes your image processing or analysis portable by allowing you to import existing workflows or share new workflows across your organization. You can apply the template to items within a mosaic dataset or to the mosaic dataset as a whole. You can also save out the raster function template as an *.rft.xml file. The workflow to use the template involves selecting the physical *.rft.xml file on disk and applying it using the batch editor or the function pane.

Question 13

T/F: Raster function templates can be used to store and share function chains.

Answer 13

True

Question 14

T/F: The advantage of using functions is that they are calculated only on the portion of image shown on the screen at the resolution displayed.

Answer 14

True

Question 15

What is the result of an NDVI function?

Answer 15

A single-band dataset, mostly representing vegetation in grayscale

Question 16

How can you access out-of-the-box raster functions in ArcGIS Pro?

Answer 16

From the Imagery tab, open the Raster Functions pane.

Question 17

Which four questions would you need to consider before applying a specific raster data processing technique using functions? (Choose four.)

Answer 17

Do you need to build a generalized template that can be applied to any dataset or should it be data-specific?

Should the output be written to a new dataset?

Do you need to extract a subset of the dataset available?

Does the dataset adequately cover the study area?

Question 18

Which workflow would be applicable to creating and organizing your processes?

Answer 18

Create a new category, copy or import functions to your category, and save the category.

Question 19

Which functionality should you use to build a raster function chain?

Answer 19

Function Editor

Question 20

You have created a change/no change image using functions in ArcGIS Pro. You need to share this image with a peer for future analysis. Which option would you use to manage the output of the image before sharing?

Answer 20

Export the raster dataset.

Question 21

You have obtained two multispectral images, covering the same area and taken during different time intervals, that are identical in size and grid resolutions. These images are also vertically aligned. You want to run a pixel-to-pixel comparison with these images to perform change detection over time. Which tool or function should you use?

Answer 21

Use the Minus function or the Difference tool on the Imagery tab.

Question 22

You would like to apply the NDVI function on a Landsat 8 image to measure the amount of vegetation present in a given pixel. Which step should you perform to calculate the index?

Answer 22

You should change the Visible Band ID to 4 and the Infrared Band ID to 5

Question 23

T/F: All outputs from the dynamic image processing are permanent rasters written to the default geodatabase.

Answer 23

False

Question 24

T/F: A function chain works in such a way that the output of one raster function becomes the input to the raster function applied on top of it in the chain.

Answer 24

True

Question 25

You have obtained GeoEye-1 imagery with clouds in some areas. You want to exclude the areas with clouds. Which function is appropriate to perform this exclusion?

Answer 25

Clip

Question 26

Which capability is an advantage of raster function chains?

Answer 26

Do multiple or sequential on-the-fly processing

Question 27

T/F: All outputs from the dynamic image processing are permanent rasters written to the default geodatabase.

Answer 27

False

Question 28

You have acquired multispectral Landsat 8 images from two time periods for identifying land use and land cover change. You have reclassified the pixel values of the image into two image values by creating a binary image: 1 for change and 0 for no change. Which function should you use to symbolize this binary image so that all pixels with a value of 1 are shown in red?

Answer 28

Attribute Table function

Question 29

Which pane can be used to perform on-the-fly processing of raster datasets in ArcGIS Pro?

Answer 29

Raster Functions pane