US Patent 7725918 Interactive television with embedded universal time codes

An interactive television (ITV) system transmitting ITV content created and received by different ITV platforms via a single ITV stream. The system provides universal time codes which are embedded into the ITV stream. Each time code is associated with a program identifier which uniquely identifies a particular program. An ITV receiver receives the ITV stream and compares the program identifier and time code with a program held in the receiver's memory. When a match is found, an interactive event indicated by the program is executed. The program may be loaded into the receiver's memory using a back channel.