Provided is to create a document file for drawing a picture finely, without increasing a file size. When a size of a first file computed before a process of vectorization is smaller than a size of a file of a manuscript, a process of vectorization is performed. When a size of a second file computed in the process of vectorization is smaller than the size of the file of the manuscript, a process after an end of the process of vectorization is performed. When a size of a third file computed in the process after the end of the process of vectorization is smaller than the size of the file of the manuscript, a vectorization file that is written in vectorized data is generated.