Cue mark inserter for editing video tape - has pulse generator and mixer for inserting bar cue marks

摘要

The mark appears as a vertical bar across the picture area at a predetermined time before a cue is to be applied. The bar may be black, white or coloured. A trigger pulse is generated and mixed with the picture signal to produce the cue or sync. mark. A picture and sound replay unit (1) feeds its picture signal output (2) into the sync mark mixer equipment (3) before it is displayed on a monitor (5). A process control unit (7) may be used for storage of the information relating to sync/cue mark application. A trigger pulse (6) is output from the process control (7) or replay unit (1). A pulse length is selected for the required purpose and transmitted through the sync mark scan generator (9), when triggered by the incoming pulse (6), into the mixer stage (4) for mixing with the picture signal. The mixer equipment (3) also contains separator stages (11), coupled through to the mixer (4) from sync recognition stages (12), for the removal of sync/cue marks.