DESC:HDMI (High-Definition Multimedia Interface) is a open industry standard audio/video interface to transfer (a) uncompressed video data and (b) compressed or uncompressed digital audio data from an HDMI-compliant source device viz. a display controller, to a compatible computer monitor, video projector, digital television, or digital audio device. It is a digital replacement for analog video standards.

High-bandwidth Digital Content Protection (HDCP) is a form of digital copy protection developed by Intel Corporation to prevent copying of digital audio & video content as it travels across connections.

HDMI which is a multimedia interface normally used in consumer electronic devices is now a days increasingly used in commercial devices e.g. digital cinema servers.

It uses HDCP protocol for link encryption. Cryptanalysis researchers have demonstrated flaws in several versions of HDCP. It is highly vulnerable due to ease in availability of HDCP stripper. They remove HDCP information from the video signal in order to allow the data to flow freely to a non-HDCP compliant display. This poses severe security concern for applications where HDMI is used to carry high value content e.g. in case of movie theatres, video output of the premium digital cinema content of play out server is connected to movie projector via HDMI link. Such scenario offering effortless illegal access to premium content causes its copyright infringement & circuitously nurturing to a potential point of origin of piracy.

Inventors have proposed technological solution to overcome the said limitations of HDCP in the HDMI link.

INVENTION

Aforesaid limitation of HDMI-HDCP based unsafe linkage is addressed in following steps
1. Superimposition of additional layer of security over HDCP Link encryption

a) Scramble the content before encoding.
b) Scrambling the content in the cinema server before sending it out on to HDMI.

2. Create a converter which will convert HDMI to HD-SDI (High definition Serial digital
Interface HD-SDI – a family of digital video interface with nominal data rate of 1.485 Gbit/s) link with CineLink’s Encryption technology. Fig 1
Option 2 is preferable, but option 1 is used if the cinema server doesn’t have the capability to scramble the content before sending it out onto HDMI.
Fig 2 reproduces the Steps inside HDMI to HD-SDI conversion

1. The converter box takes in a HDMI. This HDMI is protected using HDCP standard link encryption and also inventor’s additional scrambling on top of HDCP.

2. It first strips off the HDCP and feeds the signal to De-Scrambler block. This descrambler then removes the scrambling which inventors has added on top of HDCP.

3. The clear signal is then fed into cinelink encryption block which does the standard cinelink encryption and feeds the signal to HD-SDI transmitter.

4. The HD-SDI transmitter than transmits the signal outside the box over HD-SDI interface.

Benefit

1. This innovative significantly improves the security of the entire interface of devices thereby makes safe exhibition of premium copyrighted content.

2. System does not need any alteration in play out server and projector.

3. Incorporation of intermediate device i.e. converter box and additional scrambling makes the solution significantly more secure.

,CLAIMS:1 A SYSTEM TO PROCESS DIGITAL SIGNAL FOR SECURED TRANSMISSION OVER HDMI LINKAGE by means of Superimposition of additional layer of security over HDCP Link encryption by means of interfacing a convertor box which execute Scrambling the content before encoding by means, data encryption and authentication to protect digital content from a given media e.g. DVD from being illegally copied, distributed, and viewed from other devices such as computer hard drives,
Scrambling the content in the cinema server before sending it out on to HDMI by management of digital rights and encryption process,
Creating a converter which will convert HDMI to HD-SDI Encrypting with cinelink And
Transmission through HD SDI transmitter

2 A method of to process digital signal for secured transmission over HDMI linkage by means of scrambling the content before encoding and also scrambling the content in the cinema server before sending it onto HDMI.

3 A converter as in claim 1 to convert HDMI to HD-SDI comprising of application of embedded hardware and software, it can go for larger length compare to only HDMI cable

4 A HD SDI converter comprising of embedded hardware and software enables to port the compressed video and audio signal via HDMI to to non-HDCP complaint display in most secured manner