Nearly 150 years after they had been recorded, promising specimens of Scott de Martinville's phonautograms, stored among his papers in France's patent office and at the Académie des Sciences, were located by American audio historians. High-quality images of them were obtained. In 2008, the team played back the recordings as sound for the first time. Modern computer-based image processing methods were used to accomplish the playback. The first results were obtained by using a specialized system developed for optically playing recordings on more conventional media which were too fragile or damaged to be played by traditional means. Later, generally available image-editing and image-to-sound conversion software, requiring only a high-quality scan of the phonautogram and an ordinary personal computer, were found to be sufficient for this application.