Compared to analog format TV and movie video, HD digital format has a huge advantage. It not only has higher definition indicators, but also multimedia content stored in digital format can be stored indefinitely. You don't have to worry about film deterioration. Problems such as image quality, no matter how long it is stored, the picture clarity is always the same. Second, the high-definition video standard unifies television and movies, and enhances the commonality of multimedia content.
However, the convenience of the high-definition digital format has also caused headaches for many film manufacturers and digital content producers. Digital media is easy to be copied and compressed, and it is easy to spread around, coupled with advances in computer technology and video editing software technology. So that anyone can easily become a pirate producer.
In the foreseeable future, the bandwidth of users accessing the Internet will continue to increase, and P2P downloads will also have an increasingly wide-ranging group. If there is no strong measure to cope with this situation, it will seriously affect the healthy development of the audio-visual industry. HDCP high-definition digital content protection technology is the technological product that emerged in this context.
The main reason for organizing this HDCP knowledge article is: According to the latest news received by "New Life of Video and Audio", SONY (Sony) recently launched the first domestic media player FMP-X10 that provides high-quality 4K content. Display devices (including TVs and projectors) must pass the HDCP2.2 content protection protocol, otherwise they will not play properly.
It is understood that Sony's 4K TVs and projectors can meet the HDCP2.2 content protection protocol. Other brand models of display devices require everyone to check whether they pass this agreement before purchasing.
Below, "Video and New Life" will give you a detailed introduction to the technical overview and development and application of HDCP for your reference.
I. Overview of HDCP Technology
In the era of HDTV (HDTV), in order to adapt to the high bandwidth of HDTV, HDMI appeared. HDMI is a high-definition digital interface standard that provides high bandwidth and lossless transmission of digital video and audio signals. In order to ensure that high-definition signals transmitted by HDMI or DVI are not illegally recorded, HDCP technology has emerged.
The HDCP (High-Bandwidth Digital Content Protection) specification is led by Intel (Intel) and is an important anti-piracy technology developed for HD movies and TV programs to ensure that digital images and sound data pass. DVI or HDMI interface will not be illegally copied when sent. HDCP specifications are protected by a number of patents, and anyone who wants to implement HDCP must apply for authorization.
Basically, to play HDCP-protected audio and video content such as Blu-rayDisc, PlayStation 3 games (when output via HDMI), both source (player or computer graphics) and monitor (television or projector) must have HDCP built-in The key chip can be played normally. If any one of the system is not equipped with this key chip, the image quality may be degraded or even images may not be played. Second, the basic technical principle of HDCP
The main goal of HDCP is to prevent unencrypted high-definition video and audio content from being illegally copied and transmitted. To this end, three systems have been designed for HDCP to achieve this goal:
1. Calibration protocol. A verification process to prevent unauthorized devices from receiving high-definition content;
2, pixel encryption. Encrypt data transmitted through HDMI, DVI, etc. to prevent data from being stolen or cracked;
3. Updateability. A key revocation mechanism to ensure that any device that violates the HDCP protocol can be excluded relatively easily.
In the HDCP transmission process, both the transmitting end and the receiving end store an available key set. These keys are secretly stored. Both the transmitting end and the receiving end perform encryption and decryption operations according to the key. In this operation, a special one is added. Value KSV (Video Encryption Key). At the same time, each device of HDCP will have a unique KSV serial number, and the cryptographic processing unit at the transmitting end and the receiving end will check the KSV value of the other party to ensure that the connection is legal.
The HDCP encryption process processes each pixel so that the picture becomes irregular and unrecognizable. Only the sender and receiver receiving the synchronization can perform reverse processing to complete the data restoration. During the decryption process, the HDCP system performs a connection confirmation every 2 seconds, and simultaneously performs a synchronization identification code between the transmitting end and the receiving end every 128 frames to ensure synchronization of the connection.
In order to deal with the situation of key leakage, HDCP has specially established a "revoked key" mechanism. If certain machines are considered to be compromised, their KSV parameters will be blacklisted. If the KSV at the receiving end is found to be in the blacklist by the transmitting end, the transmitting end will refuse to transmit the content.
Third, the application and development of HDCP
As mentioned earlier, HDCP requires the support of both hardware and software. Any device that participates in content transmission is indispensable. Basically, HD movie programs after DVD use HDCP anti-piracy technology, and video source playback and display terminal devices also need to implement secondary encoding/decoding of signals through built-in conversion chip, including display cards, DVD players, and TVs. , monitors, projectors, etc. In terms of interfaces, HDCP is currently implemented mainly through the digital interface DVI-D or HDMI, and the latter is more common, and has both audio/video transmission, which almost becomes a symbol supporting HDCP.
In July 2011, the HDCP specification released a revised version 2.1, which added support for wireless WiFi, Ethernet, USB and other interfaces. It can support compressed or uncompressed high-definition audio and video content transmitted wirelessly, and updated the encryption system. The 1024-bit RSA encryption technology is used to improve the security of the system. At present, in the international market, especially in Europe and the United States, the latest HDCP2.2 technology has also been widely used in Blu-ray discs and players, HD set-top boxes, game consoles and Other Products. Sony's second-generation 4K player, the FMP-X10, requires a device that matches it to meet the HDCP 2.2 content protection protocol.
Domestic HDCP technology is mainly used in high-definition display devices and Blu-ray playback devices, such as high-definition televisions, displays, Blu-ray DVDs and other devices. For high-definition set-top boxes, its HDMI interface hardware generally has built-in HDCP function, but to enable this function, software must be used together, and HDCP authentication is required to obtain a legal key. The source of program broadcast in domestic set-top boxes mainly comes from satellite, cable, ground and other program operators. Most of the content does not use HDCP encryption, and the high-definition film and television program sources are also scarce. Therefore, most HD set-top boxes sold in China do not have this feature enabled.
At present, high-definition video is getting more and more popular, which can be seen from the broadcast TV programs in developed countries, the video resources in the Internet, and the large-screen terminal output devices. Because high-definition content is digital, copying and storing are fairly easy, and there is no distortion. It is no wonder that content providers represented by film producers/publishers strongly support HDCP technology and strive to be in HDTV/movie and interactive network formats. This content protection feature was deployed on all personal terminal devices before the massive emergence. Welcome to the home theater network!
Conclusion: With the increasing emphasis on the protection of intellectual property rights in China, consumers' awareness of intellectual property rights continues to increase, and foreign programs will gradually enter the domestic market. Coupled with the participation of domestic programming companies, I believe the domestic market will be even more Mature, products that support HDCP technology interfaces and high-quality audio and video content will increasingly enter our lives.
remote control car motor,rc boat engine,rc helicopter motor,slot car motors,toy motor price,toy dc motor
Shenzhen Maintex Intelligent Control Co., Ltd. , https://www.maintexmotor.com