The Three Parameters of HDTV Broadcast Systems
Have you gone shopping for a new HDTV lately? In looking at the different TVs, have you ever wondered what 1080i25 stands for? Well, these are based on the parameters of the HDTV broadcast system.
There are three parameters of HDTV broadcast systems. The first is the frame size in pixels. A pixel is like a dot of color that is used to make an image on the screen. So, the frame size in pixels would be, how many pixels are used to make up the frame size, this is the 1080 in the example above.
The second parameter of HDTV broadcast systems is the scanning system. There are two types: progressive scanning (p) and interlaced scanning (i). The scanning refers to the way that the lines that make up an image move across the screen. With progressive scanning, the lines of each frame are drawn in sequence. With interlaced scanning, only the odd lines, then the even lines are drawn alternately.
The last parameter of HDTV broadcasts systems is the frame rate. This is based on the number of video frames per second.
Now when you are browsing through HDTVs, you will have a little better understanding of what 1080i25 stands for.