On the navigation bar, there is a link to the Not tagged yet section. That section displays all images that have no annotation. It's working exactly in the same way as any other gallery view. You can click on any image to access an Image view.
When you are on an Image View, the navigation bar on the left displays all the concepts attached to the project. Every toggle turned to green means the corresponding concept is associated with the image.
By playing with the toggles, you can then edit the annotations attached to an image:
You can navigate to the next or previous images by using the left and right arrows of your keyboard, or by clicking on the left and right arrow buttons.
To take advantage of the gallery views, you can also make a selection and apply an annotation to all the images that you have previously selected. Here is how you can do that:
Go to a gallery view
Start a selection by hovering on an image and clicking on the small grey icon on the top left corner of the image
You can add as many images as you want to your selection by simply clicking on those images.
Once images are selected, you can click on Change tags, create or modify the annotation and then click on Apply. This will apply the same annotation to all images in your selection and the page will reload. It is likely that some images disappear from the gallery: this is normal and simply means that you have turned the toggle of the current concept to red.
To annotate an image with bounding boxes, you need to access an Image View. There, you can click on the eye icon, next to ANNOTATIONS, on top of the navigation bar: this will either hide or show the image annotations.
To create a new bounding box, click on Add a box, select the concept for this new box, and draw it on the image. You can either:
click on the position to position the first corner of the box and without releasing the click, drag the mouse pointer to a second corner. By releasing the mouse, this will create a box.
click on the position of a first corner of your box, release the mouse, then click on the second corner of your box, and release the mouse. This will create a box.
You can also remove a box directly from the navigation bar, by clicking on the trash icon.
Finally, you can edit a box by clicking on the pencil on the top right corner above the image. Don't forget to save your modifications once you are satisfied.