Distribution of coded files is increasingly growing. Signal processing after coding increases with the growth of distribution, and is becoming a significant burden in the media environment. New signal processing methods of addition, multiplication, and exchanging of coded regions are becoming important for suppressing delay, reducing the amount of calculation, and maintaining picture quality. Some of these processing had been tried as manipulating compressed images[1-2]. The B-picture in the MPEG algorithm is a barrier in realizing these processing ideals. A new coding algorithm in the future should meet a new criterion to evaluate operational convenience of the coded region together with the conventional rate and distortion criterion. In this presentation we consider examples of signal processing of the coded region, such as logo insertion and non-linear editing. The logo insertion replaces parts of a coded file by other coded logo data. The problem of moving frame is analyzed. Non-linear editing of the coded region cannot be completed for MPEG data. A number of conditions for maintaining picture quality are presented.