Video telephone system

• US 5,444,477 A
• Filed: 10/22/1993
• Issued: 08/22/1995
• Est. Priority Date: 10/23/1992
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Kawasaki, Takafumi, Fukano, Masumi, Matsubara, Takashi, Ishida, Kiyoshi, Shibata, Yoji, Takatsuki, Hiroaki, Yamadera, Hitoshi, Yoshida, Atsuo, Ishinabe, Iwao
• Primary Examiner(s): Kuntz, Curtis
• Assistant Examiner(s): Chan, Jason
• Application Number:
  US08/139,745
• Time in Patent Office: 669 Days
• Field of Search: 348/14-20, 348/564, 348/565, 379/201, 379/202, 379/203, 379/204, 379/205, 379/212
• US Class Current: 348/14.07
• CPC Class Codes: H04M 3/58 Arrangements for transferring received calls from one subscriber to another; Arrangements affording interim conversations between either the calling or the called party and a third party substation line holding circuits H04M1/80
• CPC Class Codes: H04M 3/60 Semi-automatic systems, i.e. in which the numerical selection of the outgoing line is under the control of an operator
• CPC Class Codes: H04N 7/142 Constructional details of the terminal equipment, e.g. arrangements of the camera and the display

Abstract

A video telephone system which includes a master video telephone terminal (secretary terminal) connected to a communication network and slave video telephone terminals (executive terminals) connected to the master video telephone terminal in which the master video telephone terminal can transfer a call to the slave video telephone terminals. When a call comes into the secretary terminal from a remote terminal on the communication network, a line control section of the secretary terminal sets up a line. Video data and speech data received on the line are decoded by a video signal coding-decoding section and an aural signal coding-decoding section and the decoded signals are output through a display and a speech output device. Sound and images picked up by a microphone and a camera respectively are coded for transmission. Then, if a predetermined instruction of call transfer to an executive terminal is entered on an electronic tablet of the secretary terminal, a communication branch control section of the secretary terminal calls the executive terminal, sets up a line between the secretary and executive terminals on a local transmission network, and connects the line between the secretary terminal and the remote terminal.

Claims

1. A video telephone system comprising:

a master video telephone terminal connected to a communication network; and

a plurality of slave video telephone terminals connected to said master video telephone terminal;

(I) wherein said master video telephone terminal comprising;

video generating means for generating a video signal,

means for coding the video signal generated by said video generating means,

speech generating means for generating an aural signal;

means for coding the aural signal generated by said speech generating means,

a multiplexing-demultiplexing section which multiplexes the coded aural signal and the coded video signal for transmission and separates out a coded aural signal and coded video signal from a received signal,

a line control section which controls calls on the communication network and transfer of the multiplexed coded aural and video signals through the communication network,

means for decoding the separated-out coded video signal,

means for decoding the separated-out coded aural signal,

means for outputting speech represented by the decoded aural signal,

means for displaying an image represented by the decoded video signal,

input means for accepting an instruction of a user of said master video telephone terminal,

a communication branch control section which controls calls between said master video telephone terminal and said plurality of slave video telephone terminals and transfer between said line control section or said multiplexing-demultiplexing section and said plurality of slave video telephone terminals, and

device control means being responsive to the instruction entered through said input means for specifying operation of said communication branch control section;

(II) wherein each of said plurality of slave video telephone terminals comprises;

video generating means for generating a video signal,

means for coding the video signal output by said video generating means,

speech generating means for generating an aural signal,

means for coding the aural signal output by said speech generating means,

a multiplexing-demultiplexing section which multiplexes the coded aural signal and the coded video signal for transmission and separates out a coded aural signal and coded video signal from a received signal,

a line control section which controls calls between said master and slave video telephone terminals and transfer of the multiplexed coded aural and video signals between said master and slave video telephone terminals,

means for decoding the separated-out coded video signal,

means for decoding the separated-out coded aural signal,

means for outputting a speech represented by the decoded aural signal,

means for displaying an image represented by the decoded video signal,

input means for accepting an instruction of a user and

device control means responsive to the instruction entered through said input means, for specifying operation of said line control section.

2. A video telephone system as claimed in claim 1 wherein said master video telephone terminal further comprises:

means, when multiplexed coded aural and video signals are being transferred between said line control section of the master video telephone and a called or calling slave video telephone terminal, for sending a message to said slave video telephone terminal; and

wherein each of said slave video telephone terminals further comprises;

means, upon receipt of the message from said master video telephone terminal, for overlaying characters or graphics corresponding to contents of the received message on the screen of said means for displaying.

3. A video telephone system as claimed in claim 1 wherein said input means of each of said master and slave video telephone terminals is an electronic tablet comprising a transparent input panel for reading handwritten information mounted on a display panel that can be controlled by said device control means.

4. A video telephone system comprising:

a master video telephone terminal connected to a communication network; and

a plurality of slave video telephone terminals connected to said master video telephone terminal;

(I) wherein said master video telephone terminal comprises;

(i) a line control section which controls a plurality of calls on the communication network at the same time,

(ii) a communication branch control section which controls a plurality of calls between said master video telephone terminal and said plurality of slave video telephone terminals at the same time, and

(iii) transfer controlling means for controlling transfer of calls after communications with the master video telephone terminal are started, in any one of;

(a) a first mode wherein a plurality of calls controlled by said line control section are transferred to a slave video telephone via said communication branch control section at the same time,

(b) a second mode wherein each of a plurality of calls controlled by said line control section is transferred to a slave video telephone, respectively, via said communication branch control section at the same time, and

(c) a third mode wherein each of a plurality of calls, between each of said slave video telephones, controlled by branch control section is transferred to another slave video telephone respectively via said communication branch control section at the same time; and

(II) wherein each of said plurality of slave video telephone terminals comprises;

(i) a line control section which controls a plurality of calls between said master and slave video telephone terminals at the same time.

5. A video telephone system as claimed in claim 4 wherein each of said master and slave video telephone terminals is a video telephone terminal which can communicate simultaneously with video telephone terminals at a plurality of points and has means for displaying images received from the video telephone terminals at the points on a plurality of screens into which a full screen is split.