Tools

Performance

class FPS

Monitor the frames per second (FPS) of video streams for performance tracking.

Typical usage:

fps = edgeiq.FPS().start()
while True:
    <main processing loop>
    fps.update()

# Get the elapsed time and FPS
fps.stop()
print("Elapsed seconds: {}".format(fps.get_elapsed_seconds()))
print("FPS: {}".format(fps.compute_fps()))

compute_fps() may also be called in the main processing loop to compute an instantaneous estimate of the FPS.

start()

Start tracking FPS.

stop()

Stop tracking FPS.

update()

Increment the total number of frames examined during the start and end intervals.

Raises

RuntimeError

get_elapsed_seconds()

Return the total number of seconds between the start and end intervals.

Returns

float – The elapsed time in seconds between start and end, or since start if stop() has not been called.

compute_fps()

Compute the (approximate) frames per second.

Returns

float – the approximate frames per second.

parse_cvat_annotations(path, start_frame=0, end_frame=None, new_id_for_occlusion=False)

Parse CVAT dumped annotations file to edgeIQ Predictions

Parameters

• path (str) – The path of CVAT dumped ground truth annotations (.xml)

• start_frame (int) – Starting Frame

• end_frame (Optional[int]) – Ending Frame (default: None -> Parses all available frames)

• new_id_for_occlusion (bool) – Associates a new object_id to predictions if occluded in previous frame

Returns

dict – Frame-By-Frame Data {frame_num: list of ObjectDetectionPrediction}

Return type

Tuple[dict, dict]

Returns

dict – Object-By-Object Data {object: {‘tracked_frames : list of frames in which object was tracked, ‘occluded_frames’ : list of frames in which object was occluded}}

Raises

FileNotFoundError if file doesn’t exist

Raises

ValueError if start frame is greater than end

class ModelPerformanceAnalyzer(ground_truth_path, start_frame=0, end_frame=None)

Get statistics to analyse the performance of models.

Typical usage:

analyzer = edgeiq.ModelPerformanceAnalyzer(ground_truth_path = 'annotations.xml')
model_results = edgeiq.load_analytics_results('logs/analytics.txt')
analyzer.set_results(model_results)
analyzer.write_analysis_output(output_dir = 'output', filename_suffix = '1', iou_threshold = 0.3)

Parameters

• ground_truth_path (string) – The path of CVAT dumped (for Videos) ground truth annotations file (.xml)

• start_frame (int) – Starting Frame

• end_frame (int) – Ending Frame

set_results(results)

Set the model detections list to analyse

Parameters

results (list of ObjectDetectionResults) – The list of ObjectDetectionResults to use for analysis.

get_detections_per_object(iou_threshold=0.01)

Get percentage detections per object

Parameters

iou_threshold (float) – Minimum IOU required to associate model detection with ground truth

Returns

dict

get_iou_distribution(iou_threshold=0.01, bins=10)

Get distribution of IOU

Parameters

• iou_threshold (float) – Minimum IOU required to associate model detection with ground truth

• bins (int) – Number of bins to distribute in

Returns

tuple – (Array of counts, Array of bin floors)

get_overlap_distribution(iou_threshold=0.01, bins=10)

Get distribution of Overlap

Parameters

• iou_threshold (float) – Minimum IOU required to associate model detection with ground truth

• bins (int) – Number of bins to distribute in

Returns

tuple – (Array of counts, Array of bin floors)

get_missed_detections(iou_threshold=0.01)

Get missed detections per objects

Parameters

iou_threshold (float) – Minimum IOU required to associate model detection with ground truth

Returns

dict – {ground_truth ID : list of missed frames}

get_class_based_stats(iou_threshold=0.01)

Get per class statistics like number of True Positives, False Positives, False Negatives, precision and recall for the class

Parameters

iou_threshold (float) – Minimum IOU required to associate model detection with ground truth

Returns

dict – {class_name : { num_gt: , num_detections: , TP: ,FP: ,FN: , precision: , recall: }}

write_analysis_output(output_dir='output_data', filename_suffix='', iou_threshold=0.01)

Compute all available stats and write data to csv files.

class_stats.csv -> Per class values for True Positives, False Positives, False Negatives, precision and recall object_stats.csv -> Per object values for ground truth, detections and %correct detections distribution_stats.csv -> IOU and Overlap distributions of True Positives

Parameters

• filename_suffix (string) – Suffix to be added at the end of the generated filenames

• iou_threshold (float) – Minimum IOU required to associate model detection with ground truth

class TrackerPerformanceAnalyzer(annotations_path, max_distance, start_frame=0, end_frame=None)

Analyze tracker performance against ground truth annotations.

TrackerPerformanceAnalyzer compares tracker results to ground truth annotations and collects data for two of the main performance flaws of tracking: ID changes and ID swaps.

ID changes occur when the tracker assigns a new tracker ID to an existing object. This can happen for a number of reasons

• Object became occluded

• Object was lost and found by tracker (tracker parameters are too tight)

• Object ID was swapped with another object (this is examined more closely in ID swap analysis)

The impact of ID changes on the performance of your app depends on the scenario, but a typical result is logging more unique object than there actually were. ID changes can often be overcome by higher-layer analysis to associate objects that were occluded or lost.

ID swaps occur when an object is assigned a tracker ID that was previously assigned to another. This can be very hard to recover from, since it is hard to detect in real-life use cases. The most common causes are

• Objects occlude each other

• Tracker parameters are too loose

The impact of ID swaps on the performance of your app will be combining metrics from multiple objects into a single object.

Typical usage:

start_frame = 0
end_frame = 2000
tpa = edgeiq.TrackerPerformanceAnalyzer(
        annotations_path='path/to/cvat/annotations.xml',
        start_frame=start_frame,
        end_frame=end_frame,
        max_distance=5)

for frame_idx in range(start_frame, end_frame - 1):
    frame = load_annotation_frame(frame_idx)
    frame = tpa.markup_image(frame_idx, frame, (255, 100, 0))

    # Get predictions and tracker results
    tpa.update(frame_idx, tracked_objects)

report = tpa.generate_report().write_to_file(output_dir=path/to/save/dir)

Parameters

• annotations_path (str) – The path of CVAT dumped ground truth annotations (.xml)

• start_frame (int) – The start frame to load annotations for.

• end_frame (Optional[int]) – The end frame to load annotations for, or None to load all remaining.

• max_distance (int) – The max distance to be used for matching tracked objects with annotations.

Raises

FileNotFoundError if annotation file doesn’t exist

Raises

ValueError if start frame is greater than end

get_annotation_predictions(frame_idx)

The predictions for the given frame loaded from the annotations.

Parameters

frame_idx (int) – The frame index to read annotations from.

Return type

list

Returns

List of predictions

update(frame_idx, tracked_results)

Match a new set of tracker results with the ground truth results from annotations.

Parameters

• frame_idx (int) – The frame index to read annotations from.

• tracked_results (TrackingResults) – The output of an Object Tracker

markup_image(frame_idx, frame, color)

Draw boxes, centers, and matching radius of ground truth predictions on the frame.

Parameters

• frame_idx (int) – The frame index to read annotations from.

• frame (ndarray) – The image to draw on

• color (Tuple[int, int, int]) – The color to draw the center and radius

Return type

ndarray

generate_report()

Generate the TrackerPerformanceReport.

Return type

TrackerPerformanceReport

class TrackerPerformanceReport(report)

The Tracker Performance Report generated by TrackerPerformanceAnalyzer

property id_change_report

The ID change report.

The ID change report is a dictionary with the format:

{
    'num_objects_with_id_changes': <>,
    'objects_with_id_changes': <>,
    'total_id_changes': <>,
    'id_change_events_by_frame': <>,
    'id_changes_by_ground_truth_id': <>
}

Return type

dict

property id_swap_report

The ID change report.

The ID change report is a dictionary with the format:

{
    'num_objects_with_id_swaps': <>,
    'id_swaps_by_ground_truth_id': <>,
    'total_object_swaps': <>,
    'id_swap_events_by_frame': <>
}

Return type

dict

write_to_file(output_dir)

Write the reports to files.

This function will save ‘id_swap_report.json’ and ‘id_change_report.json’ to the provided directory.

Parameters

output_dir (str) – The directory to save the reports in

Image Manipulation

translate(image, x, y)

Translate an image.

Parameters

• image (numpy array of image) – The image to manipulate.

• x (integer) – Translate image on X axis by this amount.

• y (integer) – Translate image on Y axis by this amount.

Returns

numpy array – The translated image.

rotate(image, angle)

Rotate an image by specified angle.

Parameters

• image (numpy array of image) – The image to manipulate.

• angle (integer) – The angle to rotate the image by (degrees).

Returns

numpy array – The rotated image.

resize(image, width=None, height=None, keep_scale=True, inter=3)

Resize an image to specified height and width.

When both a width and height are given and keep_scale is True, these are treated as the maximum width and height.

Parameters

• image (numpy array of image) – The image to manipulate.

• height (integer) – The new height of image.

• width (integer) – The new width of image.

• keep_scale (boolean) – Maintain the original scale of the image.

• inter (integer) – The interpolation method (One of OpenCV InterpolationFlags).

Returns

numpy array – The resized image.

markup_image(image, predictions, show_labels=True, show_confidences=True, colors=None, line_thickness=2, font_size=0.5, font_thickness=2)

Draw boxes, labels, and confidences on the specified image.

Parameters

• image (numpy array of image in BGR format) – The image to draw on.

• predictions (list of ObjectDetectionPrediction) – The list of prediction results.

• show_labels (boolean) – Indicates whether to show the label of the prediction.

• show_confidences (boolean) – Indicates whether to show the confidence of the prediction.

• colors (list of tuples in the format (B, G, R)) – A custom color list to use for the bounding boxes. The index of the color will be matched with a label index.

• line_thickness (float) – The thickness of the lines that make up the bounding box.

• font_size (float) – The scale factor for the text.

• font_thickness (float) – The thickness of the lines used to draw the text.

Returns

numpy array – The marked-up image.

transparent_overlay_boxes(image, predictions, alpha=0.5, colors=None, show_labels=False, show_confidences=False)

Overlay area(s) of interest within an image. This utility is designed to work with object detection to display colored bounding boxes on the original image.

Parameters

• image (numpy array of image in BGR format) – The image to manipulate.

• predictions (list of ObjectDetectionPrediction) – The list of prediction results.

• alpha (float in range [0.0, 1.0]) – Transparency of the overlay. The closer alpha is to 1.0, the more opaque the overlay will be. Similarly, the closer alpha is to 0.0, the more transparent the overlay will appear.

• colors (list of tuples in the format (B, G, R)) – A custom color list to use for the bounding boxes or object classes pixel map

• show_labels (boolean) – Indicates whether to show the label of the prediction.

• show_confidences (boolean) – Indicates whether to show the confidence of the prediction.

Returns

numpy array – The overlayed image.

pad_to_aspect_ratio(image, a_ratio)

Pad an image to a certain aspect ration. Padding is added to the bottom and right of the image

cutout_image(image, box)

Cut out the portion of an image outlined by a bounding box.

Parameters

• image (numpy array of image) – The image to cut out from.

• box (BoundingBox) – The bounding box outlining the section of the image to cut out.

Returns

numpy array – The segment of the image outlined by the bounding box. Will be independent from the original image.

blur_objects(image, predictions)

Blur objects detected in an image.

Parameters

• image (numpy array of image) – The image to draw on.

• predictions (list of ObjectDetectionPrediction) – A list of predictions objects to blur.

Returns

numpy array – The image with objects blurred.

perform_histogram_equalization(image, color_space='GS', adaptive=False, clip_limit=2.0, tile_grid_size=(8, 8))

Performs Histogram Equalization on the input image and returns the equalized image.

Histogram equalization is a basic image processing technique that adjusts the global contrast of an image by updating the image histogram’s pixel intensity distribution. Doing so enables areas of low contrast to obtain higher contrast in the output image. This function includes implementations of both basic and adaptive histogram equalization. The basic histogram equalization will spread pixels to intensity “buckets” that don’t have as many pixels binned to them. Mathematically, what this means is that the function is applying a linear trend to the image’s cumulative distribution function (CDF). The adaptive histogram equalization function divides an input image into an M x N grid, and then applies equalization to each cell in the grid, resulting in a higher quality output image.

Parameters

• image (numpy array of image (Gray Scaled or in BGR format)) – The image on which we will do Histogram Equalization operation.

• color_space (string) – The color space of the image on which we will do Histogram Equalization. Supported color_space parameters: [“GS”, “YCrCb”, “YUV”, “HSV”, “LAB”]. If ‘color_space’ = “GS”, output image will be in gray scaled format(2D array). If ‘color_space’ != “GS”, output image will be in BGR format(3D array).

• adaptive (boolean (either True or False)) – Whether we want to enable adaptive Histogram Equalization or not.

• clip_limit (float/integer) – The clip limit value for Adaptive Histogram Equalization. The ‘clip_limit’ is used only if ‘adaptive’ = True. ‘clip_limit’ value is the threshold for contrast limiting. Typically it is adviced to use the value ranging from 2-5. Allowed range is 0-40. Larger values results in more local contrast and more noise. Try to keep the ‘clip_limit’ value as low as possible.

• tile_grid_size (list/tuple/array of length 2 (integer values only)) – Number of grids we want to divide the image into for Adaptive Histogram Equalization. The ‘tile_grid_size’ is used only if ‘adaptive’ = True.

Returns

numpy array – The image after doing Histogram Equalization(Gray Scaled or in BGR format)

perform_gamma_correction(image, gamma_value=0.8, color=False)

Performs gamma correction operation on the input image and returns the corrected image.

Gamma correction is done when you want to control a camera sensor’s color and luminace. Gamma correction is also known as the Power Law Transform: O = I ^ (1 / G) I = imput image O = scaled back to the range [0, 255] G = gamma value, should be greater than 0. For gamma values < 1 will shift the image towards the darker end of the spectrum For gamma values > 1 will shift will make the image appear lighter For gamma value of 1 will have no effect

Parameters

• image (numpy array of image (2D or 3D array)) – The image on which we will do Gamma Correction operation.

• color (boolean (either True or False)) – True will do gamma correction on BGR image and False on Gray-Scaled image. If ‘color’ = True, the output image will be in BGR format(3D array). If ‘color’ = False, the output image will be gray sclaed format(2D array).

• gamma_value (float/integer) – The gamma value for Gamma Correction.

Returns

numpy array – The image after doing Gamma Correction(2D or 3D array)

blend_images(foreground_image, background_image, alpha)

Blend a foreground image with a background image, foreground image and background image must have the same dimensions and same color format (RGB/BGR).

Parameters

• foreground_image (numpy array of image) – The image to be scaled by alpha in the blend.

• background_image (numpy array of image) – The image to be scaled by 1 - alpha in the blend.

• alpha (float in range [0.0, 1.0]) – The ratio of foreground to background image in the blend.

Returns

numpy array – The blended image.

overlay_image(foreground_image, background_image, foreground_mask)

Overlay a foreground image with a background image according to the foreground mask.

This function will mask both the foreground and background images, then combine them into the output image.

Parameters

• foreground_image (numpy array of image in BGR format) – The image to be overlaid on the background.

• background_image (numpy array of image in BGR format) – The image for the foreground to be overlaid on.

• foreground_mask (numpy array of image in BGR format) – A mask with white indicating foreground and black indicating background. Shades in between will blend the foreground and background accordingly.

Returns

numpy array – The overlaid image.

Filesystem

list_images(base_path, contains=None)

List all images in specified path.

Finds images with the following extensions:

• .jpg

• .jpeg

• .png

• .bmp

• .tif

• .tiff

Parameters

• base_path (string) – The base path of folder where images are located.

• contains (string) – Select only filenames that contain this string.

Returns

list of strings – The valid image file paths.

list_files(base_path, valid_exts=('.jpg', '.jpeg', '.png', '.bmp', '.tif', '.tiff'), contains=None)

List all files in specified path.

Parameters

• base_path (string) – The base path of folder where files are located.

• valid_exts (list of strings) – The list of valid extentions to filter for.

• contains (string) – Select only filenames that contain this string.

Returns

list of strings – The valid file paths.

Results Filtering

filter_predictions_by_label(predictions, label_list)

Filter a prediction list by label.

Typical usage:

people_and_apples = edgeiq.filter_predictions_by_label(predictions, ['person', 'apple'])

Parameters

• predictions (list of ObjectDetectionPrediction) – A list of predictions to filter.

• label_list (list of strings) – The list of labels to keep in the filtered output.

Returns

list of ObjectDetectionPrediction – The filtered predictions.

filter_predictions_by_area(predictions, min_area_thresh)

Filter a prediction list by bounding box area.

Typical usage:

larger_boxes = edgeiq.filter_predictions_by_area(predictions, 450)

Parameters

• predictions (list of ObjectDetectionPrediction) – A list of predictions to filter.

• min_area_thresh (integer) – The minimum bounding box area to keep in the filtered output.

Returns

list of ObjectDetectionPrediction – The filtered predictions.

Results Serialization

to_json_serializable(results_input)

Takes in core Computer Vision service results, such as ObjectDetectionResults, ClassificationResults, HumanPoseResult, InstanceSegmentationResults, or results returned by calling the update() method on any of the tracking classes, such as CentroidTracker and returns them in a JSON-serializable format.

Typical usage:

...
results = obj_detect.detect_objects(frame, confidence_level=.5)
results = edgeiq.to_json_serializable(results)

Parameters

results_input (A core Computer Vision service result object.) – The object to serialize.

Returns

a json serlializable object.

HW Discovery

find_usb_device(id_vendor, id_product)

Check if a USB device is connected.

Parameters

• id_vendor (integer) – The vendor ID.

• id_product (integer) – The product ID.

Returns

True if device found, otherwise False

find_ncs2()

Check if an NCS2 is connected.

Note that once a connection to the NCS2 is opened, the device’s VID and PID will change and this function will no longer find it.

Returns

True if NCS2 found, otherwise False

is_jetson()

Determine if running on a NVIDIA Jetson device.

Returns

True if running on a NVIDIA Jetson device, otherwise False

is_jetson_nano()

Determine if running on a NVIDIA Jetson Nano.

Returns

True if running on a NVIDIA Jetson Nano, otherwise False

is_jetson_xavier_nx()

Determine if running on a NVIDIA Jetson Xavier NX.

Returns

True if running on a NVIDIA Jetson Xavier NX, otherwise False

is_jetson_agx_xavier()

Determine if running on a NVIDIA Jetson AGX Xavier.

Returns

True if running on a NVIDIA Jetson AGX Xavier, otherwise False

Analytics

class CustomEvent(results)

Store the attributes of this result.

Parameters

results (dict) – The custom event data parsed from the analytics file.

property results

The custom event data parsed from the analytics file.

Type

dict

property tag

The tag for the custom event.

Type

any

load_analytics_results(filepath)

Load results from file published by the alwaysAI Analytics Service.

Parameters

filepath (string) – The full path to the file to load.

Returns

A list of the deserialized results. Each deserialized result will include a tag property.

Typical usage:

deserialized_results = edgeiq.load_analytics_results('logs/analytics.txt')
left_camera_results = [result for result in deserialized_results if 'left' in result.tag]
right_camera_results = [result for result in deserialized_results if 'right' in result.tag]

publish_analytics(results, tag=None)

Publish data to the alwaysAI Analytics Service

Parameters

• results (JSON-serializable object.) – The results to publish.

• tag (JSON-serializable object) – Additional information to assist in querying and visualizations.