Keyed, true-transparency image information combine

Abstract From the Canadian patent

The disclosed keyed, true-transparency combine and keyer receive a plurality of image information signals Vi each having a corresponding input, key signal Bkj over a respective channel. The image signals can be dynamically ranked in a defined prioritized order even on a field-by-field, basis. However rather than switch the individual image signals as their prioritized order changes, the order of the channels is dynamically and switchably interchanged within a keyer means by switchably interchanging a plurality of substantially identical keyer units while generating a plurality ofprocessed true transparency image key signals Pki. The keyer units are substantially identical in the sense that …