A communication interface unit of a facsimile and a transformer for preventing a power source noise. The oxide semiconductor may include GaZnON, and a proportion of Ga content to a total content of Ga and Zn of the channel layer is about 0. The image prototyping environment enables the user to easily apply various image processing functions to an image and immediately see the results, in order to develop the desired algorithm. In response to a directory enumeration request from a client computer, one or more directories of metadata files on one or more of the file servers is enumerated, instead of enumerating the data file that store the user file portions.