1. Composing apparatus for selecting segments from image source material stored in at lease one storage medium and for denoting serially connected sequences of said segments, said apparatus comprising: a pictorial display means; an operator control means; at least one first random access storage medium for storing a plurality of duplicate counterparts of image source material; and a composing control means responsive to said operator control means for controlling said storage media, said random access storage medium, and said pictorial display means, said composing control means comprising: means for denoting a start and an end of each of a plurality of segments of said source material; means for identifying each said segment by at least one pictorial image segment label; means for selectively displaying segments of said image source material on said pictorial display means; means for assembling at least a plurality of said labels into a serially connected label sequence; operator responsive means for locating any said segment by displaying said pictorial labels in said label sequence; and said displaying means being further adapted for displaying the segment identified by a selected label.