To connect two divided and multiplexed streams seamlessly, a gap between video and audio playback times has to be adjusted. And, to make this adjustment, every conventional method has been required to process mass data by extracting and re-encoding the elementary streams and re-arranging the data, so that the data cannot be handled by any video cameras.However, the present invention has successfully solved the above conventional problems as follows. An audio packet disposed at the start of a following stream to be connected is replaced with a null packet if its playback start time precedes that of the video packet. Then, soundless audio packets are added at the end of the preceding stream, thereby eliminating the gap between video and audio playback times in both of the streams to realize the required seamless connection.