The present invention discloses methods of archiving and optimizing lectures, presentations and other captured video for playback, particularly for blind and low vision individuals. A digital imaging device captures a preselected field of view that is subject to periodic change such as a whiteboard in a classroom. A sequence of frames is captured. Frames associated with additions or erasures to the whiteboard are identified. The Cartesian coordinates of the regions of these alterations within the frame are identified. When the presentation is played back, the regions that are altered are enlarged or masked to assist the low vision user. In another embodiment of the invention, the timing of the alterations segments the recorded audio into chapters so that the blind user can skip forward and backward to different sections of the presentation.