46 – 1280x720 HDTV

Publisher Summary This chapter highlights the scanning, timing, and sync structure of 1280x720 video, also called 720p. The scanning and timing information in the chapter applies to all variants of 720p video, both analog and digital. 720p video represents stationary or moving two-dimensional images sampled temporally at a constant rate of 24/1.001, 24, 25, 30/1.001, 30, 50, 60/ 1.001, or 60 frames per second. The chapter also focuses on the scanning parameters depicting through a table. A frame comprises a total of 750 horizontal raster lines of equal duration uniformly scanned top to bottom and left to right, numbered consecutively starting at 1. Of the 750 total lines, 720 contain picture. At a digital interface, video information is identified by a timing reference signal (TRS) conveyed across the interface. The chapter also indicates that analog interfaces are discouraged for all but the three highest-rate systems (720p60, 720p59.94, and 720p 50). Analog signal timing is defined by the digital standard; the digital sampling frequency defines reference time intervals used to define analog timing.