The HDMI HDCP

HDCP, namely High-bandwidthDigital Content Protection technology. The age of HDTV has arrived, with the advent of HDMI to accommodate the high bandwidth of HDTV. HDMI is a high definition digital interface standard that provides high bandwidth for nondestructive transmission of digital video and audio signals. HDCP technology comes into being to ensure that high-definition signals transmitted by HDMI or DVI are not illegally recorded. The HDCP specification, led by Intel, protects the content by interfering with the illegal copying of high-definition signals, reducing the quality of the copied images.

The protection principle of HDCP:

HDCP technology protects the entire transmission of audio and video content. For example, on the computer platform, when the video and audio content protected by HDCP technology is exported, the COPP (CertifiedOutput Protection Protocol) driver in Microsoft operating system firstly verifies the video card, and only the video card supporting HDCP can realize the content output. The operating system then authenticates the display device's key, and only devices that meet HDCP requirements can finally display the video content delivered by the card.

In the whole process of transmission, both the sender and the receiver store a set of available keys, which are secretly stored, and the sender and receiver encrypt and decrypt according to the key.

Conclusion:

The HDCP protocol is used to prevent video content from being copied completely during transmission. Rather than making it impossible for digital signals to be recorded illegally, the technology encrypts them so that they cannot be recorded at high resolution. For example, a Blu-ray player cannot record a clear program while playing a high-definition disc, or a program on a monitor when playing a disc on a computer. HDCP protects the video signal from start to finish, which means that every part of the playback system must support the HDCP protocol. If the display does not support THE HDCP protocol, then it will not be able to properly play high-definition programs, only black screen or low quality shows. DVI, HDMI and other digital video interfaces must be used to support HDCP protocol. Traditional analog signal interfaces such as VGA cannot support HDCP protocol. When using the analog signal interface such as VGA, the picture will decline to low picture quality, or prompt cannot play, thus losing the meaning of HD. It should be noted that HDCP is embedded in the HDMI interface, and HDCP is supported on all displays with HDMI interfaces. However, not all LCD displays with DVI interface support HDCP protocol, and must be certified with the corresponding hardware chip.