evaluateDetectionAOS

(To be removed) Evaluate average orientation similarity metric for object detection

Since R2020a

evaluateDetectionAOS will be removed in a future release. Use evaluateObjectDetection instead.

Syntax

metrics = evaluateDetectionAOS(detectionResults,groundTruthData)

metrics = evaluateDetectionAOS(detectionResults,groundTruthData,threshold)

Description

metrics = evaluateDetectionAOS(detectionResults,groundTruthData) computes the average orientation similarity (AOS) metric. The metric can be used to measure the detection results detectionResults against ground truth data groundTruthData. The AOS is a metric for measuring detector performance on rotated rectangle detections.

metrics = evaluateDetectionAOS(detectionResults,groundTruthData,threshold) additionally specifies the overlap threshold for assigning a detection to a ground truth bounding box.

Examples

Evaluate Rotated Rectangle Detections

Define ground truth bounding boxes for a vehicle class. Each row defines a rotated bounding box of the form [xcenter, ycenter, width, height, yaw].

gtbbox = [
    2 2 10 20 45
    80 80 30 40 15
    ];

gtlabel = "vehicle";

Create a table to hold the ground truth data.

groundTruthData = table({gtbbox},'VariableNames',gtlabel)

groundTruthData=table
      vehicle   
    ____________

    {2x5 double}

Define detection results for rotated bounding boxes, scores, and labels.

bbox = [
    4 4 10 20 20
    50 50 30 10 30
    90 90 40 50 10 ];

scores = [0.9 0.7 0.8]';

labels = [
    "vehicle"
    "vehicle"
    "vehicle"
    ];
labels = categorical(labels,"vehicle");

Create a table to hold the detection results.

detectionResults = table({bbox},{scores},{labels},'VariableNames',{'Boxes','Scores','Labels'})

detectionResults=1×3 table
       Boxes           Scores            Labels      
    ____________    ____________    _________________

    {3x5 double}    {3x1 double}    {3x1 categorical}

Evaluate the detection results against ground truth by calculating the AOS metric.

metrics = evaluateDetectionAOS(detectionResults,groundTruthData)

metrics=1×5 table
                AOS        AP       OrientationSimilarity     Precision         Recall   
               ______    _______    _____________________    ____________    ____________

    vehicle    0.5199    0.54545        {4x1 double}         {4x1 double}    {4x1 double}

Input Arguments

detectionResults — Detection results

three-column table

Detection results, specified as a three-column table. The columns contain rotated rectangle bounding boxes, scores, and labels.

Bounding Box	Format	Description
Rotated rectangle	[xcenter, ycenter, width, height, yaw]	This type of bounding box is defined in spatial coordinates as an M-by-5 matrix representing M bounding boxes. The xcenter and ycenter coordinates represent the center of the bounding box. The width and height elements represent the length of the box along the x and y axes, respectively. The yaw represents the rotation angle in degrees. The amount of rotation about the center of the bounding box is measured in the clockwise direction.

groundTruthData — Labeled ground truth images

datastore | table

Labeled ground truth images, specified as a datastore or a table.

• If you use a datastore, your data must be set up so that calling the datastore with the read and readall functions returns a cell array or table with two or three columns. When the output contains two columns, the first column must contain bounding boxes, and the second column must contain labels, {boxes,labels}. When the output contains three columns, the second column must contain the bounding boxes, and the third column must contain the labels. In this case, the first column can contain any type of data. For example, the first column can contain images or point cloud data, such as:

  data	boxes	labels
  The first column must be images.	Bounding boxes	The third column must be a cell array that contains M-by-1 categorical vectors containing object class names. All categorical data returned by the datastore must contain the same categories.

• If you use a table, the table must have two or more columns.

  data	boxes	...
  The first column can contain data, such as point cloud data or images.	Each of the remaining columns must be a cell vector that contains M-by-5 matrices representing rotated rectangle bounding boxes. Each rotated rectangle must be of the form[xcenter, ycenter, width, height, yaw]. The vectors represent the location and size of bounding boxes for the objects in each image.

threshold — Overlap threshold

nonnegative scalar

Overlap threshold, specified as a nonnegative scalar. The overlap ratio is defined as the intersection over union.

Output Arguments

metrics — AOS metrics

five-column table

AOS metrics, returned as a five-column table. Each row in the table contains the evaluation metrics for a class which is defined in the ground truth data contained in the groundTruthData input. To get the object class names:

metrics.Properties.RowNames

This table describes the five columns in the metrics table.

Column	Description
AOS	Average orientation similarity value
AP	Average precision over all the detection results, returned as a numeric scalar. Precision is a ratio of true positive instances to all positive instances of objects in the detector, based on the ground truth.
OrientationSimilarity	Orientation similarity values for each detection, returned as an M-element numeric column. M is one more than the number of detections assigned to a class. The first value of OrientationSimilarity is 1. Orientation similarity is a normalized variant of the cosine similarity that measures the similarity between the predicted rotation angle and the ground truth rotation angle.
Precision	Precision values from each detection, returned as an M-element numeric column vector. M is one more than the number of detections assigned to a class. For example, if your detection results contain 4 detections with class label 'car', then Precision contains 5 elements. The first value of Precision is 1. Precision is a ratio of true positive instances to all positive instances of objects in the detector, based on the ground truth.
Recall	Recall values from each detection, returned as an M-element numeric column vector. M is one more than the number of detections assigned to a class. For example, if your detection results contain 4 detections with class label 'car', then Recall contains 5 elements. The first value of Recall is 0. Recall is a ratio of true positive instances to the sum of true positives and false negatives in the detector, based on the ground truth.

References

[1] Geiger, A., P. Lenz., and R. Urtasun. "Are we ready for autonomous driving? The KITTI vision benchmark suite." IEEE Conference on Computer Vision and Pattern Recognition. IEEE, 2012.

Version History

Introduced in R2020a

R2023b: evaluateDetectionAOS will be removed in a future release

The evaluateDetectionAOS function will be removed in a future release. Use the evaluateObjectDetection function to evaluate object detection results with metrics such as the AOS, instead.