Nippon Hoso' Kyokai

Haruo Okuda

Yutaka Tanaka

Taiji Nishizawa

Taiichiro Kurita

Kazumasa Enami

Shoichi Suzuki

Kaoru Watanabe

Toshiyuki Takegahara

Kazuhiko Shibuya

Yasuaki Kanatsugu

Minoru Honda

Hideki Suganami

Ryoichi Yajima

Hisakazu Kato

Toshihiro Uehara

Yoshio Takeuchi

Yoshinori Izumi

Seiichi Gohshi

Masaru Kanazawa

Junji Kumada

Isao Kondo

Yusei Nishimoto

Makoto Okui

Tatsuya Kurioka

Yoshiharu Hoshino

Seiichi Namba

Satoru Koizumi

Makoto Tadenuma

Ichiro Yuyama

Hiroyuki Hamazumi

Sumio Yano

A method of transmitting a content to a reception side includes the steps of encrypting the content by use of a scramble key that varies with time, encrypting scramble-key-associated information that includes at least the scramble key and usage-control information, the usage-control information indicative of usage of the content on the reception side, and transmitting the encrypted content and the encrypted scramble-key-associated information to the reception side.

Control of usage of contents in digital broadcasts

High resolution vertical and horizontal components of a high definition video signal are combined with a standard broadcast system video signal, such as the NTSC system, in which high frequency horizontal resolution components are sampled and used to modulate at least a first sub-carrier signal. The first sub-carrier is frequency interleaved onto the standard broadcast signal. Vertical high resolution components are time compressed and time division multiplexed onto top and bottom portions of the standard broadcast signal. The modified broadcast signal can be decoded by a standard receiver to display a standard resolution video image, while receivers designed to decode the modified signal can time division demultiplex the vertical high resolution components and demodulate the horizontal high resolution components, combine these components with the standard components, and generate a high definition video image.

Receiver and channel compatible encoding/decoding system for high

A signal transmission system for high definition television that can handle a second television signal which is superior in quality to a first television signal such as an NTSC (National Television System Committee) television signal. The transmitting end of the system transmits a first television signal including a video signal, audio signals, etc., through a main transmission line, as well as a third television signal including a high definition components obtained as the difference between the second and the first television signal through an auxiliary transmission line. The receiving end of the system receives and synthesizes the first television signal transmitted through the main transmission line and the third television signal transmitted through the auxiliary transmission line to produce the second television signal.

Signal transmission system for high definition television

A method and system for multiplexing additional audio information in the form of pulse code modulation (PCM) audio signals onto a television signal. The PCM audio signal is time multiplexed into scanning retrace intervals of the video signal. At a receiver, the bit error rate of the decoded PCM audio signal is compared with a threshold so as to switch the audio output from the PCM audio signal to a conventional FM demodulated audio signal when the bit error rate exceeds the predetermined threshold. In this way, the benefits of both PCM audio and FM audio can be obtained by utilizing the higher immunity of FM signals in low signal-to-noise ratio environments, while the high fidelity PCM audio signal is utilized when the signal-to-noise ratio environment is relatively high.

Method and system for transmitting and receiving PCM audio signals in

Growing community of inventors

Tokyo, Japan

Haruo Okuda