text: Title: How to work with images without objects?
  Body: Hello!
  I want to detect an object type in an image. I mean, I have only 1 class. The thing is that I have images without that object but I am very interested in evaluating the algorithm on those images to see if it is a proponent of false positives on that type of images.
  The solution I have adopted is to add the name of the image in the images field of the coco json without adding any annotation related to that image.
  That is, let's suppose that the image with id=1 does not have the object I want to segment, no annotation linked to the image with id=1 will appear. Is the approach I have taken correct?
  
  Thank you very much