How to calculate metrics for a Roboflow exported YOLO11 dataset?

[robmarkcole]

I've found in the cheatsheet:

import supervision as sv
from supervision.metrics import F1Score

predictions = sv.Detections(...)
targets = sv.Detections(...)

f1_metric = F1Score()
f1_result = f1_metric.update(predictions, targets).compute()

print(f1_result)
print(f1_result.f1_50)
print(f1_result.small_objects.f1_50)           

How should I pass the image & labels to sv.Detection? My objective is to overlay the prediction on the truth, but more significantly, to calculate the metrics for that image (and also to filter e.g. by area of detection)