Fujitsu Corporation

Kiyokatsu Iijima

Ryota Akiyama

Tetsu Tanizawa

Kiyoshi Kohiyama

Kiyotaka Ogawa

Nobuhiko Nishio

Muneharu Gotou

A DES decrypting unit decrypts video data frames encrypted and compressed based on MPEG standards, when receiving them. The decrypted video data frames are expanded one by one in a MPEG expansion circuit. Each time the single frame is expanded, the MPEG expansion circuit outputs a completion-of-frame-expansion signal to a host control CPU. The host control CPU counts the completion-of-frame-expansion signals and reduces an accounting count value in an accounting data memory in accordance with this count value. The host control CPU output character pattern image data from a pattern generator when the accounting count value becomes 0. The character pattern image data is superimposed on a video signal in an adder circuit.

Apparatus for managing software using quantity

A scrambling method of a stream formed of a series of unit streams in succession, the unit stream including a first stream part and a second stream part located behind the first stream part. The scrambling method scrambles the second stream part by using a random number generator and includes a step of supplying predetermined data included in the first stream part and having a non-fixed value, for each of the second stream part to be scrambled, to the random number generator as an initial value. Further, a scrambling apparatus, a descrambling method and a descrambling apparatus are disclosed.

Scrambling and descrambling of data with improved security

Growing community of inventors

Kawasaki, Japan

Kiyokatsu Iijima