Abstract: A system for inserting text data (e.g., closed caption data) contained In a user data or image data of an MPEG stream into the scanning line H21 of the Image signal recovered from the MPEG stream through a simplified process. In case of text data in the user data, the image data is decoded compressed image data on the video-CD is expended and stored as video data in the first memory location, and the closed caption data in the user data area is NRZ-modulated and stored in the second memory location. The caption data is read out of the second memory location and output to a bit map pixel data channel during a period of H21 of the output video data stream, and the video data Is read out of the first memory location and output to an video pixel data channel in the periods after H22 of the output video data stream. Thus, the two data are multiplexed on a bus.