Kabushiki Kaisha Toshiba

Mitsubishi Denki Kabushiki Kaisha

Toru Terauchi

Jun Sato

Keiko Watanabe

Tsutomu Owa

Koji Nakashima

Shigeru Tashiro

Satoshi Miyagawa

In a data structure of a multimedia file format, a movie box and a media data box are provided. In each box, a non-encrypted size field, a non-encrypted type field and box data field are provided. In box data of the movie box, information data regarding multimedia data is stored. The multimedia data is encrypted and stored in box data of the media data box. The information data is obtained by referring to the container in the movie box. This information data is held as encryption and encoding information data. By referring to the information data, a data unit of the encrypted multimedia data in the media data box is obtained, and the unit data is decrypted.

Data structure of multimedia file format, encrypting method and device thereof, and decrypting method and device thereof

A terminal device determines whether a clock is a secure clock or a self-running clock. If the clock is the self-running clock, the device stores a clocking time of the clock as a timestamp file in a memory card in recording content. In playing back the content, the device determines validity of a clocking time using the timestamp file to play back the content and also updates the stored time of the stored time as the timestamp file to a content playback start time. In contrast, if the clock is the secure clock, the device stores the timestamp file indicating a recording time of the content in the memory card only in recording the content and omits updating the stored time as the timestamp file in playing back the content.

Terminal device

When content owned by a source device are played back in a rendering device, a content key is transferred from the source device to the rendering device via a secure session every time playback is carried out. Then, encoded content are decoded and played back to be outputted by using the transferred content key so as to discard the content key after the end of playback.

Information terminal

A mobile communication terminal moves and backs up a content, which was downloaded from a content server, to a personal computer. When the mobile communication terminal receives an encryption key generation request from the personal computer via a cable, the mobile communication terminal extracts information to be used for generating the encryption key and generates the encryption key by using the extracted information and own telephone number. And the generated encryption key is transmitted to the personal computer via the cable. Accordingly, the backed up and moved content can be reproduced with the personal computer.

Mobile communication terminal

According to an aspect of the invention, there is provided a content sharing system including: a first device configured to acquire a right object; a second device configured to acquire a content of the right object from the first device; a session key generation unit provided in the first device and the second device and configured to generate a session key based on mutual authentication; a temporary right object generation unit provided in the first device and configured to generate a temporary right object from the right object by using the session key to supply the generated temporary right to the second device; and a content play unit provided in the second device and configured to receive the temporary right object to play the content of the right object acquired from the first device by using the temporary right object.

Content sharing system and method

An information terminal according to this invention includes a storage means having a first storage area which is accessible from an external terminal, and a second storage area which is inaccessible from the external terminal. Content which includes a content body and rights information indicating a use condition given to the content body is acquired. The acquired content is encrypted and the encrypted content is stored in the first storage area. In addition, state management information used to manage the variable state of the use condition given to the content body is generated on the basis of the rights information included in the acquired content, and the generated state management information is stored in the second storage area.

Information terminal and content storage/playback method

A download control program of a client terminal transmits a request to a download server, which stores Download Descriptors that include attribution information of contents, for a Download Descriptor, and receives the Download Descriptor from the download server. The download server, before transmitting the Download Descriptor to the client terminal, adds information indicating that there is a difference between a Download Descriptor contained in the request from the client terminal and the Download Descriptor stored in data memory of the download server if the download server detects the difference between them. The client terminal transmits a content download request to a contents server based on the received Download Descriptor.

System for downloading contents, and client terminal for downloading contents from contents server

A management information generating section generates management information in which the correspondence between content data and rights data is described when a digital DCF container containing encrypted content data and a rights object described in association with a right which decrypt the content data are stored in an external media card. A backup section writes the DCF container, rights object and management information onto the external media card.

Information terminal device and content backup method

The terminal device is equipped with a location judgment database which stores setting data indicating the relationships between the location of the self device and the corresponding object to be presented to the user. On the basis of the location detection data obtained by detecting the location of the self device by receiving range signals transmitted by a plurality of GPS satellites and the setting data stored in the location judgment database, corresponding objects are selected from a plurality of objects received and decoded and they are synthesized and presented as they are output to the display or the speaker. Thus, an optimal object presentation can be achieved in accordance with the status of the terminal device.

Digital broadcasting system and terminal therefor

Digital mobile communication equipment a voice power calculating section for calculating the voice power of digital voice signals converted by the A/D conversion section ; a noise level comparing section for comparing the results from the voice power calculating section with a threshold level indicating noise level, and for replacing the voice signals with other signals such as all &ldquo;0&rdquo; data or comfort noise when the voice signals are determined to be at noise level, a voice coding section for coding the output of the noise level comparing section , and a forward error correction coding section for conducting forward error correction coding.

Growing community of inventors

Tokyo, Japan

Toru Terauchi