US Patent 10895954 Providing a graphical canvas for handwritten input

The subject technology provides rendering an image in a first view including a plurality of tiles, each tile comprising image data corresponding to a portion of the image. The subject technology, responsive to detecting an initiation of touch input corresponding to the image, copies the image data from the plurality of tiles to a graphical canvas. The subject technology displays the image data in the graphical canvas in a second view, the graphical canvas being overlaid over at least a portion of the rendered image. The subject technology receives input stroke data corresponding to the second view, the input stroke data being continuous with the touch input. The subject technology responsive to detecting that the touch input has ended, copies the input stroke data to the plurality of tiles of the first view. Further, The subject technology displays the input stroke data and the image in the plurality of tiles of the first view.