ATSC, or Advanced Television Systems Committee, is an international organization mainly concerned with transmission technologies. ATSC defines the standards for digital television technologies and transmission in the United States and in other countries such as Canada, Mexico, and South Korea.
ATSC aims to replace NTSC (National Television Systems Committee), an earlier analog standard. The ATSC standards are created by a group consisting of associations in the electronic industry, electrical engineers, an association of broadcasters, and organizations in the fields of cable TV and motion picture.
ATSC has standards for enhanced video and audio features. These standards include High Definition TV (HDTV), an advanced technology with a higher image aspect ratio than most types of TVs. ATSC standards also include the Standard Definition Television (SDTV). Satellite direct-to-home is another technology included in ATSC standards.
Apart from digital video transmission, high-quality audio has also been incorporated in ATSC standards. Devices providing multi-channel surround-sound audio support these standards.
A number of specific technologies are used by ATSC standards. These technologies contribute to the enhancement of video and audio features of the aforementioned devices. ATSC makes use of 8-level Vestigial Side-Band or 8VSB modulation. This type of modulation has gained recognition for its advanced power saving features. Another technology used by ATSC is MPEG-2 compression. MPEG-2 compression enables broadcasters to give video streams with higher resolutions and audio streams with better sound quality. ATSC uses AC3 encoding, a technology used by numerous systems and networks for audio output.
HDCP means High-Bandwidth Digital Content Protection, a content protection system designed to end the likelihood of illegal transmission of High-Definition entertainment. It blocks unofficial digital interception and replication between a player and a monitor.
In the past, a digital signal maintains absolute clarity, even if it has been recopied plenty of times. This is unfavorable for businesses holding copyright items when their programs are being copied and widely distributed without their permission.
HDCP has changed this by requiring the digital audio and video interface to follow the guidelines of the Digital Content Protection Group. If the rules are not met, the multimedia equipment will not play the high-definition programs.
How It Functions
HDCP functions to protect the contents of a disc by means of encryption and authentication. The source device, which is always a media player, will prepare to transmit the protected High–Definition video content into a display device using a link that supports HDCP. The two devices must identify each other first and exchange a set of numbers called the Key Selection Vector (KSV). KSV is composed of 40 unique combinations, which need to be exchanged to determine if they are registered and legal. In the swapping of numbers, each will produce 56 bits to be used for encryption.
How Video Is Displayed
A source device like a DVD player or an HDTV tuner has to encrypt the signal and send that signal through the link to the receiving device such as a monitor or TV. If one of the devices is not HD compliant, an error will occur. The requirements for viewing a High-Definition video are the following:
- HDCP-enabled graphics card;
- Blu-Ray or HD-DVD drive;
- HD compliant monitor; and
- DVI or HDMI monitor connection.
Consumers are advised to be aware of HDCP, especially in buying home entertainment sets. There are at least two products in the market which can deliver perfect resolution: the Blue Ray and the HD DVD. It is a sensible decision to buy only HDCP-compliant appliances so they can be used in applications requiring HDCP compliance in the future.
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