Input MPEG compressed data is input into a partial decoder and a logo insertion controller. A block DCT coefficients (a) output from the partial decoder is divided into a logo insertion region (c) and a non-logo insertion region (d) in a logo insertion region separator. Logo data (e) supplied from a logo information supply section is combined into the logo insertion region (c) with an arbitrary mixing ratio in a logo information insert section. In a logo region partial re-encoder, intra-frame coding of an image insertion region is executed when a starting frame for inserting an image is an intra-coded frame or a predictive coded frame, and, when the starting frame is a bidirectionally predictive-coded frame, inter-frame coding of the image insertion region is executed, and intra encoding of the image insertion region is executed in a frame to which the starting frame for inserting the image can refer.