A stream editing system is provided which is designed to switch one of two input streams used in an editing operation to the other at an edit point set in each of the streams. The system includes two decoders and at least one encoder. In the editing operation to combine the two streams to produce a single stream, the system re-encodes only a trailing portion of one of the streams with a leading portion of the other stream which are defined across the edit points and uses the other portions of the streams as they are, thereby minimizing a deterioration in signal quality caused by the re-encoding of the streams.