Color Transient Improvement (CTI) is a technique for improving color television images in analog picture display. The CTI technique is used to improve abrupt color transitions and edge representation in television images from classic television standards.
The fact that colored edges in television pictures have a certain blurring is due to the difference in bandwidth
with whichthe luminance signal (Y) and the chrominance signals
(U, V or Cb and Cr) are represented. Thebandwidth difference is about 5:1. The same applies to
therise time of
luminanceand chrominance transitions, where the rise time of the luminance signal is only about one fifth of that of the chrominance signals, which results in
These distortions are compensated for by electronic circuits that improve the slope of abrupt color transitions and at the same time compensate for the resulting time differences between luminance and chrominance signals so that the edges of the two signals correlate with each other.