Hitachi, Ltd.

Pioneer Electronic Corporation

Other

Kabushiki Kaisha Toshiba

Matsushita Electric Industrial Co., Ltd.

Hitachi Consumer Electronics Co., Ltd.

Toshifumi Takeuchi

Takao Arai

Yutaka Nagai

Osamu Kawamae

Masafumi Nakamura

Masayuki Hirabayashi

Hiroshi Yoshiura

Hiroyuki Kimura

Hiroshi Hirayama

Izumi Kimura

Masayuki Inoue

Seiichi Saito

Nobutaka Amada

Hiroshi Tadokoro

Hideaki Suzuki

Junji Shiokawa

Munehiro Nishioka

Yoshiaki Moriyama

Yoshio Suzuki

Mikio Shiraishi

Michio Miura

Masaru Takahashi

Isao Echizen

Kiyoshi Kano

Yasuo Ohtsuka

Hiroo Okamoto

Tadashi Kojima

Koichi Hirayama

Fumihiko Yokogawa

Shigemitsu Higuchi

Toshiyuki Shimada

Manabu Katsuki

Kouichirou Nishimura

Kouichi Hirose

Shinichi Tanaka

Hiroaki Ono

Hisashi Yamada

Akira Maeda

Koichiro Nishimura

Manabu Sasamoto

Yuji Hatanaka

Tatsuya Ishitobi

Shinichi Obata

Akira Kurahashi

Hiroyuki Gunji

Takaharu Noguchi

Akira Ogino

Yusuke Nakamura

Shigeyuki Itoh

Susumu Yoshida

Shin-ichi Tanaka

Nobuhiro Tokushuku

Hiromichi Tanaka

Taku Hoshizawa

Akio Fukushima

Shigeki Inoue

Masakazu Ikeda

Kazumi Sugaya

Yasushi Fukuda

Toshihiro Mizukami

Junichi Taguchi

Jun Matsui

Shuichi Sagano

Jun&prime;ichi Taguchi

Daigo Fukuma

Tomoaki Kudo

Kouei Usuda

Akira Abeta

Fumihiko Pioneer Electronic Corp Yokogawa

Yoshiaki Pioneer Electronic Corp Moriyama

In an optical disk apparatus, by obtaining the temperature in the vicinity of a laser in the apparatus, the power source voltage of the laser driver is controlled such that power consumed by the headroom of the laser driver is reduced to the maximum extent without deteriorating the current drive characteristic of the headroom when the temperature becomes higher. The laser driving current of the laser driver is monitored to control the power source of the laser driver such that the power consumed by the headroom is possibly reduced while maintaining the current drive characteristic of the headroom for the monitored current.

Optical disk apparatus and information recording method

An authentication method for use in sending/receiving data between a coded data output apparatus for outputting coded data having a water mark, and a recording apparatus for recording data onto a recording medium, the method including: deciding a type of the recording medium used by the recording apparatus; based on a result of the deciding, selecting, from a plurality of authentication methods, an authentication method corresponding to the type of the recording medium, and conducting authentication between the coded data output apparatus and the recording apparatus, using the authentication method; sending/receiving data between the coded data output apparatus and the recording apparatus after conducting the authentication; and in a case where the coded data has the water mark, detecting the water mark by the coded data output apparatus, wherein the data exchanged between the coded data output apparatus and the recording apparatus is scrambled by a scrambling method corresponding to the type the recording medium.

Reproducing apparatus, recording apparatus and display apparatus

A method of reproducing data from a recording medium, each of the data including reference time information indicating a reference time and including packet data, the method including: reproducing the data from the recording medium; obtaining a difference between respective reference times indicated by the reference time information of the reproduced adjacent data; rearranging the data on a time axis such that a time interval between adjacent data is equal to the obtained reference time difference; and outputting the rearranged data.

Transmitting and recording method, reproducing method, and reproducing apparatus of information and its recording medium

A disk-like recording medium recording/reproducing method or apparatus for performing a data recording operation and a data reproducing operation to the disk-like recording medium alternately. The recording operation is performed at a constant linear velocity, and whether a recording area at an ending point of an n-th recording operation on the medium is continuous to a recording area at a starting point of an (n+1) the recording operation is identified. When a discontinuation of the recording area is identified, the rotational speed at the starting point of the (n+1)th recording operation is changed, during a reproducing operation between the n-th recording operation and the (n+1)th recording operation. When a continuation of the recording area is identified, the rotational speed of the disk-like recording medium at the ending point of the n-th recording operation is held, during a reproducing operation between the n-th recording operation and the (n+1)th recording operation.

Method and apparatus for recording/reproducing digital video signal or audio signal, and optical disk apparatus

A system effecting a data reproducing method for a plurality of devices, for sending and receiving data by authenticating the plurality of devices with each other, said data reproducing method including: selecting, from a plurality of descrambling methods, a descrambling method corresponding to a type of said data, executing authentication by an authenticating method corresponding to the selected descrambling method, where the authenticating method is selected from a plurality of authenticating methods, and reproducing said data.

An optical disk reproducing apparatus has a circuit for detecting a difference in modulation scheme between two types of optical disks in a reproduction signal and a circuit for determining the modulation schemes of the disks on the basis of the difference. Thus the apparatus can reproduce the two optical disks with use of the circuit which determines the modulation schemes of the disks to be reproduced.

Optical disk reproducing apparatus with a disk identifying function

A data reproducing method for a plurality of devices, for sending and receiving data by authenticating the plurality of devices with each other, said data reproducing method including: selecting, from a plurality of descrambling methods, a scrambling method corresponding to a type of said data, executing authentication by an authenticating method corresponding to the selected descrambling method, where the authenticating method is selected from a plurality of authenticating methods, and reproducing said data.

A digital signal recording apparatus is disclosed, which is capable of protecting the copyright of the analog input information encoded into a first digital signal in a recording medium. A second digital signal encrypted based on the key information and the input analog signal encrypted based on the key information are converted into a second digital signal and encrypted, and the resulting signal is selectively recorded in a recording medium. The digital signal recording apparatus further comprises a circuit for encrypting the digital signal converted from the input analog signal with a key obtained by a predetermined calculation of the key information according to a scheme similar to the second digital signal protection scheme through a digital interface, and a signal recording circuit for recording the key information and the encrypted digital signal in a recording medium.

Digital signal recording/reproducing apparatus

When, in the course of recording data to a disk for each basic recording unit, the recording is stopped in the middle of a basic recording unit, data of the basic recording unit of the recording that was stopped remain held in memory. When recording resumes, the recording operation is restarted sequentially from the remaining data held in memory from the position at which recording was stopped. When the remaining data cannot be recorded, dummy data are recorded instead and playback is performed, skipping the dummy data section.

Data recording device for recording data in basic recording units

A method of reproducing data from a recording medium, wherein each of the data includes reference time information indicating a reference time and packet information, includes the steps of rearranging the data on a time axis such that a time interval between adjacent data is equal to a difference between respective reference times indicated by the reference time information of the adjacent data, and outputting the rearranged data at an output rate equal to or greater than a data rate of the data. The packet information includes at least video packet information into which a compressed video signal data stream is divided, and audio packet information into which a compressed audio signal data stream is divided.

A reproducing method and apparatus for receiving and reproducing data and outputting the data into an external device. After reproducing the data, a descrambler corresponding to a type of the reproduced data is selected from a plurality of descramblers and the external device is authenticated by a selected authenticator which is included in a plurality of authenticators for authenticating the external device and corresponds to the selected descrambler, and the data is outputted.

A transmitting method of digital data whereby information data can be reproduced at a high precision. In order to retain digital data in sectors comprising a plurality of sync frames and sequentially transmit, the sync frame is comprised of the sync signal and the run length limited code which satisfies the limitations of the minimum run length and the maximum run length, and the sync signal includes the sync pattern constituted by a bit pattern of a run length that is longer than the maximum run length by onlyT and addition bit patterns which are arranged before and after the bit pattern and each of which has a urn length that is longer than the minimum run length. The sync signal includes a specific code which indicates a position in the sector and which enables the DC control to be performed.

Digital data transmitting method

A reproduction method and apparatus for reproducing video data and/or audio data from a recordable medium having video data and/or audio data recorded thereon. The video data and/or audio data is generated by superimposing information concerning an attribute of a video signal and/or an audio signal on a signal of digitized video data and/or a signal of digitized audio data. Information concerning a copyright superimposed on the video data and/or audio data is reproduced from the medium, and a type of the medium is identified. Reproduction is stopped in response to a determination that the medium is illegally produced, the determination being based on a combination of the information concerning a copyright which is reproduced and the type of the medium identified.

Reproduction apparatus and reproduction method of digital video signal or audio signal

Growing community of inventors

Yokohama, Japan

Toshifumi Takeuchi