Bounding box annotation is the most common and widely used model for machine tasks. The annotation will draw a bounding box over an object and label them with an object class. Generally, the bounding boxes are drawn tight with no loose end. The tasks seems simple but it requires meticulous effort to keep up the consistency. Bounding boxes are generally used for image annotation. Polygon annotation" is a multi point annotation technique to draw shapes,angles and curves unlike bounding box annoation which limits only to square or rectangle boxes. Polygon helps to annotate objects in angled photos and polygon shapes Cuboidal annotation" is drawing a cube over an object to get 3D perspective on height,width and depth. The cuboids are drawn on 2D images to get the 3d perspective.
An important image annotation technique which outlines the object in the image with a box, for object classification and localization models.
Semantic segmentation is a pixel-level labeling which identifies all the pixels in an image and segments it into its component objects for a more meaningful representation.
Identifying individual points like facial features and joint positions in the human body