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Classify Raster, Compute Confusion Matrix and Segment Attributes, Create Accuracy Assessment Points

Classify Raster, Compute Confusion Matrix and Segment Attributes, Create Accuracy Assessment Points Tools

Classify Raster

How to use Classify Raster Tool in Arc Toolbox??

Classify Raster Tool
Classify Raster

Path to access the tool

:

Classify Raster Tool, Segmentation and Classification Toolset, Spatial Analyst Tools Toolbox

 

Classify Raster

Classifies a raster dataset based on an Esri classifier definition (.ecd) file and raster dataset inputs.

The .ecd file contains all the information needed to perform a specific type of Esri-supported classification. The inputs to this tool must match the inputs used to generate the required .ecd file.

The .ecd file can be generated from any of the classifier training tools, such as Train Random Trees Classifier or Train Support Vector Machine Classifier.

1. Input Raster

The raster dataset to classify.

2. Input Classifier Definition File

The input Esri classifier definition (.ecd) file containing the statistics on the chosen attributes for the classifier.

3. Output Classified Raster

The path and name of the classified image you are creating.

The output classified raster is defined by the input raster dataset and .ecd file inputs.

4. Additional Input Raster (optional)

Incorporate ancillary raster datasets, such as a multispectral image or a DEM, to generate attributes and other required information for the classifier. This raster will be needed when calculating attributes such as mean or standard deviation. This parameter is optional.Additional Input Raster (optional)

 Compute Confusion Matrix

How to use Compute Confusion Matrix Tool in Arc Toolbox??

Compute Confusion Matrix Tool
Compute Confusion Matrix

Path to access the tool

:

Compute Confusion Matrix Tool, Segmentation and Classification Toolset, Spatial Analyst Tools Toolbox

 

Compute Confusion Matrix

Computes a confusion matrix with errors of omission and commission and derives a kappa index of agreement and an overall accuracy between the classified map and the reference data.

This tool uses the outputs from the Create Accuracy Assessment Points tool or the Update Accuracy Assessment Points tool.

1. Input Accuracy Assessment Points

The accuracy assessment point feature class, created from the Create Accuracy Assessment Points tool, containing the CLASSIFIED and GROUND_TRUTH fields.

2. Output Confusion Matrix

The output file name of the confusion matrix in table format.

The format of the table is determined by the output location and path. By default, the output will be a geodatabase table. If the path is not in a geodatabase, specify a .dbf extension to save it in dBASE format.

Compute Segment Attributes

How to use Compute Segment Attributes Tool in Arc Toolbox??

Compute Segment Attributes Tool
Compute Segment Attributes

Path to access the tool

:

Compute Segment Attributes Tool, Segmentation and Classification Toolset, Spatial Analyst Tools Toolbox

 

Compute Segment Attributes

Computes a set of attributes associated with the segmented image. The input raster can be a single-band or 3-band, 8-bit segmented image.

1. Input Segmented RGB Or Gray Raster

The input segmented raster dataset, where all the pixels belonging to a segment have the same converged RGB color. Usually, it is an 8-bit, 3-band RGB raster, but it can also be a 1-band grayscale raster.

2. Output Segment Index Raster

The output segment index raster, where the attributes for each segment are recorded in the associated attribute table.

3. Additional Input Raster (optional)

Incorporate ancillary raster datasets, such as a multispectral image or a DEM, to generate attributes and other required information for the classifier. This raster will be needed when calculating attributes such as mean or standard deviation. This parameter is optional.

4. Segment Attributes Used (optional)

Specifies the attributes to be included in the attribute table associated with the output raster.

  1. COLOR—The RGB color values are derived from the input raster, on a per-segment basis.
  2. MEAN—The average digital number (DN), derived from the optional pixel image, on a per-segment basis.
  3. STD—The standard deviation, derived from the optional pixel image, on a per-segment basis.
  4. COUNT—The number of pixels comprising the segment, on a per-segment basis.
  5. COMPACTNESS—The degree to which a segment is compact or circular, on a per-segment basis. The values range from 0 to 1, where 1 is a circle.
  6. RECTANGULARITY—The degree to which the segment is rectangular, on a per-segment basis. The values range from 0 to 1, where 1 is a rectangle.

If the only input into the tool is a segmented image, the default attributes are COLOR, COUNT, COMPACTNESS, and RECTANGULARITY. If an Additional Input Raster is also included as an input along with a segmented image, then MEAN and STD are available as options.

Create Accuracy Assessment Points

How to use Create Accuracy Assessment Points Tool in Arc Toolbox??

Create Accuracy Assessment Points Tool
Create Accuracy Assessment Points

Path to access the tool

:

Create Accuracy Assessment Points Tool, Segmentation and Classification Toolset, Spatial Analyst Tools Toolbox

 

Create Accuracy Assessment Points

Creates randomly sampled points for post-classification accuracy assessment.

A common practice is to randomly select hundreds of points and label their classification types by referencing reliable sources, such as field work or human interpretation of high-resolution imagery. The reference points are then compared with the classification results at the same locations.

1. Input Raster Or Feature Class

The input classification image or other thematic GIS reference data. The input can be a raster or feature class.

Typical data is a classification image (single band, integer data type), or the training polygon output from an ArcMap image classification toolbar.

If using polygons as input, only use those that are not used as training samples. They can also be GIS land-cover data in shapefile or feature class format.

2. Output Accuracy Assessment Points

The output point shapefile or feature class that contains the random points to be used for accuracy assessment.

3. Target Field (optional)

Specifies whether your input data is a classified image or ground truth data.

  1. CLASSIFIED—The input is a classified image. This is the default.
  2. GROUND_TRUTH—The input is reference data.

4. Number of Random Points (optional)

The total number of random points that will be generated.

The actual number may exceed but never fall below this number, depending on sampling strategy and number of classes. The default number of randomly generated points is 500.

5. Sampling Strategy (optional)

Specify a sampling scheme to use.

  1. STRATIFIED_RANDOM—Create points that are randomly distributed within each class, where each class has a number of points proportional to its relative area. This is the default
  2. EQUALIZED_STRATIFIED_RANDOM—Create points that are randomly distributed within each class, where each class has the same number of points.
  3. RANDOM—Create points that are randomly distributed throughout the image.

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