Abstract: An autonomous robot mainly contains an image capturing device, an interpretation device, a synthesis device, and an audio output device. The image capturing device captures pages of graphical images in which appropriate musical information is embedded, and the interpretation device deciphers and recognizes the musical information contained in the captured graphical image. The synthesis device simulates the sound effects of a type of instrument or a human singer by synthesis techniques in accordance with the recognized musical information. The audio output device turns the output of the synthesis device into human audible sounds. The graphical image of appropriate musical information is prepared in a visually recognizable form. The graphical image can also contain special symbols to give instructions to the autonomous robot such as specifying an instrument.