BT709standardeissa
BT709standardeissa, often referred to as BT.709 or simply Rec. 709, is a standard that defines high-definition television (HDTV) system parameters. Developed by the International Telecommunication Union Radiocommunication Sector (ITU-R), it was first published in 1990. The primary purpose of BT.709 is to establish a common set of specifications to ensure interoperability between different HDTV broadcasting systems and display devices worldwide.
The standard specifies several key aspects of an HDTV signal. It defines the image aspect ratio as
BT.709 has become the de facto standard for HDTV production and transmission across much of the globe.