High-definition television transition
Switchover to HD television or switch-off of SD signals / From Wikipedia, the free encyclopedia
The transition to high-definition television is a process by which standard-definition (SD) television signals are upgraded to a high-definition (HD) format.[1] In this process, channels usually either simulcast their HD signals alongside the existing SD signals or broadcast exclusively in HD. The transition to the latter is often referred to as the standard-definition television switch-off.
In most territories around the world, the complete shutdown of the lower-resolution signals has not yet begun or is still in its early stages, notably in the many countries that are still undergoing the analogue switch-off.
In territories and services where SD signals have already ceased, television sets that do not support terrestrial HD signals are required to be replaced or equipped with set-top boxes compatible with HD signals.[1][2][3] In some cases, this switch-off has led to a high demand for new set-top boxes and TV sets, resulting in shortages.[4]