# Identifying Features

When using the Blue Locate tool to identify features, follow these steps:

1. If necessary, adjust the Region of Interest (ROI) of the tool.

2. In the bottom-left corner of the display, there is a circle graphic that graphically illustrates the size of the Feature Size parameter setting.

   This circle graphic can be moved into the ROI and placed over the largest feature. Then, using the drag handle, you can adjust the Feature Size so that it approximately covers the feature.

   Note: For more information, refer to the Blue Locate Tool – Feature Size topic.

3. Within the ROI, while hovering over the image, the mouse-cursor will have a cross-hairs icon which is used to place the feature label of the Blue tool. Click on a feature to label it.

   Note: For more information, refer to the Blue Locate Tool – Labels and Markings and Blue Locate Tool – Apply Feature Label Graphics – Tips and Shortcuts topics.

4. The feature label will have a default character of 0. Enter in a meaningful character (A-Z, 0-9, up to 140 characters) to identify the feature. For identical features, you can use the same identifier.

   If there is more than one feature that you want to find in the image, identify and label each feature.

5. Go through each image in your image database and identify and label each instance of the feature(s).

   Tip: To ensure the best results, be careful and thorough in this process, ensuring that you identify and label every instance of the feature. When labeling your features, ensure that you are very accurate and precise with each feature that you label. You are establishing the ground truth for the tool, and the tool's accuracy is a direct reflection of how accurately you label the features. See Applying Labels and Blue Locate Tool – Labels and Markings for the details of labeling.
6. Add images to the training set.
   1. Select the images in the View Browser, and on the right-click pop-up menu click Add views to training set. To select multiple images in the View Browser, use the Shift + Left Mouse Button.
   2. Or, use Display Filters to show the desired images for the training only and add them to the training set by clicking Actions for ... views → Add views to training set.
7. Prior to training, you need to set parameters in Tool Parameters. You can configure Training, Sampling, Features (if necessary), and Perturbation parameters or just use the default values of these. See Blue Locate Tool Parameters for the details of the supported parameters.
   1. Ensure that the Feature Size parameter in Sampling parameters has been set. The Feature Size parameter gives the network a clue to the size of the features that you are interested in identifying. So, if the Feature Size parameter setting is clearly going off from the size of features in your application, there is a chance the tool will not identify the features in your image.
   2. If you want more granular control over training or processing, turn on Expert Mode on Help menu to initialize additional parameters in Tool Parameters.
8. Once you have added desired images to the training set, press the Brain icon to train the tool.
   1. If you stop training in the middle of it by pressing the Stop icon, you can stop training but you will lose the current tool so far trained.
   Tip: In addition to the following tips, consider using the bootstrap method of labeling your images. "Bootstrap" labeling refers to the process of beginning your labeling process by just labeling a small sample size of your images, then training the tool, and reviewing the results by accepting views with correct markings to convert them into labels, and removing incorrect markings and replacing them with correct labels. You can speed up this process further by dividing images into multiple views and only labeling a single view. In addition, you can also temporarily reduce the Epoch Count parameter (one of the ), which will make the training time shorter.

9. After training, review the results. Open Database Overview panel and review the Confusion Matrix and Precision, Recall, F-Score for each feature and each model to understand the results. See Blue Locate Tool – Statistics for the details of interpreting results.

10. After reviewing the results, go through all of the images and see how the tool correctly or incorrectly marked the features and models for each image.
    1. If the tool has correctly marked the features, right-click the image and select Accept View.

    2. If the tool has incorrectly marked the features, failed to identify a present feature, or placed a mismatch label to a feature, do the following:

       Note: If the tool has placed one or more mismatched features (indicated by an orange outline), refer to the Mismatches topic.
       1. Right-click the image and select Accept View.
       2. Right-click the image again and select Clear Markings and Labels.
       3. Manually re-label the features in the image.
11. If you encountered the scenario in (10-a), you are ready to use the tool. If you encountered the scenario in (10-b), you will need to retrain the tool and repeat the steps 7 ~ 11.