What is preserved in the PSIP of digital video signals?

The active format descriptor is an important component preserved in the Program Specific Information Protocol (PSIP) of digital video signals. PSIP is designed to help with the organization and transmission of program-related information for digital television broadcasts.

The active format descriptor specifically indicates how the video should be displayed, including aspects like the aspect ratio, whether the content is in a letterbox format, or if it needs to be stretched to fill the screen. This information is vital for ensuring that viewers receive the video in the format that best suits their display devices, which enhances their viewing experience. Proper utilization of the active format descriptor allows devices to correctly interpret and present the video without awkward cropping or distortion.

In contrast, elements like audio tracks or video compression details might be handled differently or stored in separate sections of the broadcasting protocol, and core signal information typically refers more broadly to the fundamental characteristics of the transmission itself rather than specific presentation formats. Thus, the active format descriptor stands out as a key piece of information preserved within PSIP, directly related to how the content is displayed to viewers.