Abstract: Methods for managing notes, either digital notes or images of physical notes. One feature uses multiple drawing layers divided into tiles to render drawing operations. The tiles with drawing changes are rendered in new tiles while tiles without changes are used from a previous drawing layer. This feature accommodates redo and undo commands by pushing or popping a layer on the history stack of layers. Another feature uses a displayed plus button that expands upon touch to display actions. A user can touch an action to select it and, upon releasing the touch, the action is executed with respect to displayed boards of digital notes. Another feature receives a 3D model of notes from a video scan and uses a transformation matrix to convert the notes in the 3D model to corresponding digital notes.

Abstract: Methods for managing notes, either digital notes or images of physical notes. The methods use optical character recognition to convert handwritten content into characters and icons. The methods also determine sizes of non-square physical notes when imaged by a camera from various angles. For curled notes or damaged notes such as a note missing a corner, the methods detect and process edges of a physical note in an image and, using the detected edges, convert the image of the physical note into a corresponding digital note without curl or damage.