Specialists of "Crypton" Ltd., have developed a conditional access technology for analog broadcasting, that combines merits of inexpensive systems with analog processing of the video signal of the image (Sync Suppression, Chameleon systems and so on) and systems of advanced complexity with digital processing, as a result of what a time structure of the video signal of the image gets broken (Line Share, Line Cut & Rotate, Line Shuffle Technologies and others).

    The suggested Conditional Access System has a number of advantages:

• cost of the equipment of the Conditional Access System Crypton for cable and air networks of the overland TV broadcasting is much lower, than the cost of similar equipment for a network of satellite TV broadcasting, owing to much less quantity of potential subscribers;
  
• it provides the possibility of organizing conditional access to the Pay TV channels;
  
• provides high cryptographic stability of the system within the lifetime;
  
• renews the image with the maximum quality that subjectively does not differ from the initial one.
  

    Analog processing is used for the replacement of the fixed level of sync pulses of the initial video signal in the coder, and also for their following renewal by the decoder, that allows to make the last one enough simple and inexpensive device.

    The high quality of the renewed image, in comparison with another systems with digital processing of the image video signal, is reached due to the next:

• lead-in of the distortion is fulfilled not with the transposition of the image lines or their fragment, that is why the quality of the renewed image does not depend from the quality of the transfer characteristic of the receiving-transfer section;
• in the decoder analog-digital and digital-analog transformation are absent, that excludes the appearance of the additional discredit noise.
  

    At the same time the introduced distortions are sufficient to exclude the possibility of viewing TV image without its preliminary renewal.

    The information about distortions introduced into the image, the information, that controls engaged decoders, is coded in digital data, that are introduced by the coder in subordinate lines of the field black-out interval of the video signal of the image. The base of the decoder is one-chip controller with individual number, with impenetrable from reading memory program, that makes it impossible to take a back number and to use it unapproved.

    As a rule, the ensuring of a high cryptographic stability of the system proposes the necessity of realization the digital processing of the video signal. With this purpose "Crypton" Ltd., has developed a new generation of coding devices series COD-5XX and has started their serial production.

    The coding devices series COD-5XX are compatible with the existing fleet of decoders "Crypton", that's why cable and air TV operator have only to replace the old coding equipment without replacing the existing fleet of subscriber decoders.

    Highly useful are new capabilities of the coders series COD-5XX:

• transcoding SECAM-PAL;
• video channel time delay compensation;
• creeping line insertion;
• test signal mode;
• frame synchronization of several TV channels according to one source;
• commutation of video signals from several sources.