The move from MPEG2 to the MPEG4 digital broadcasting encoding standard could create a need to turn off the MPEG2 digital TV signal, making current Freeview digital terrestrial TV (DTT) receivers obsolete.
"We are just at the cusp now of changing digital broadcasting encoding standards," said Roger Lynch, chairman of service provider Video Networks, at a Government Select Committee hearing. "The problem is that every single Freeview box out there in the field cannot do MPEG4, so what that means is: how do you ever get to the latest technology on DTT where you migrate to MPEG4, free up the spectrum and enable things like high-definition?
MPEG4 uses spectrum more efficiently, using half of the bandwidth of MPEG2, meaning twice as many channels or the ability to offer high-definition broadcasting with far less bandwidth.
Lynch agreed with the Committee that this change meant there may come a point when there is a "second switch-off" of TV signals in order to transfer from MPEG2 to MPEG4. "There will be a transition where, in an aggregate and an economic sense, it will make sense to use the most advanced encoding technology," said Lynch.
Lynch said he was concerned about the current focus on Freeview as the primary provider of digital TV because it uses MPEG2. "By placing so much emphasis on, and so much investment in that, you end up perpetuating what I call the ‘lowest common denominator’, because it is based on a legacy technology."
