Welcome to the forum @ghost 
Could you specify what you mean by "generate labels for images"?
Do you refer to how the data should be stored in the resulting dataset? You can restructure how the data is stored using before_db callback in your custom recipe. How the the data is stored by default is determined by the view_idyou use. The docs on different annotation interfaces detail the data structure they produce (you can also always inspect the annotations in the DB. You will probably want to work with choice for classifying images.
Or do you mean a custom arrangement of options in the UI? In the latter case you would need either several blocks of choice options or a custom html block. Here you can check the solution for custom options interface - you might need sth simpler if you don't need this dynamic aspect to it but it gives you an idea what it takes to create a custom choice UI.