4. A method as recited in claim 1 , wherein the implementing includes: creating a sheet music file for a piece of music, in a sheet music editor; exporting the sheet music file as vector graphics content having elements that can be identified, displayed, and highlighted, the elements representing discrete segments of the piece of music, each of the segments having a beginning and an end; obtaining an audio recording of the piece of music, the audio recording including sound-wave sampled audio; synchronizing the audio recording with the vector graphics content, such that beginning and end points within the audio recording correspond with the elements of the piece of music that represent the discrete segments thereof; and generating an electronic book file, incorporating the audio recording and the vector graphics content of the sheet music.
7. A method as recited in claim 4 , wherein, if the sheet music file contains a repeat of a section of the music that goes back, from within a current first portion to a previously played first portion, separate vector graphics content is provided for each time the section of the music is played back, whereby the highlighted playback always progresses toward the end.