Video monitoring system including a memory for storing and transmitting a video signal immediately following the occurrence of an event

Claim 2

A video monitoring system comprising: a sending station for outputting a video signal indicative of an image of an object; a receiving station including monitor means for reproducing an image from the video signal; and a communication path established between the sending station and the receiving station only when monitoring is required through the monitor means, wherein said sending station comprises: pickup means for at all times picking up the image of the object and outputting the video signal indicative of the image; memory means for storing a video signal on the object corresponding to a particular event to be monitored, said memory means including a frame memory having a capacity to store an image signal of at least one field; sensor means for detecting the occurrence of the particular event to be monitored; and control means for storing in said memory means the video signal outputted from the pickup means in accordance with the detection of the occurrence of the particular event by said sensor means and for reading the video signal stored in said memory means to transmit the video signal to said receiving station after a communication path is established between said sending station and said receiving station, wherein said control means puts said memory means in a write-enabled state in which the video signal outputted from said pickup means can be written at all times and, when said sensor means detects the occurrence of the particular event, said control means puts said memory means in a write-disabled state to maintain the video signal already stored in said memory means.

Claim 3

A video monitoring system according to claim 1, wherein said communication path includes a control signal path for transmitting a control signal to establish a logical connection between said sending and receiving stations and a video signal from said sending station to said receiving station when said sending and receiving stations are logically connected, the video signal outputted from said pickup means and the video signal stored in said memory means being transmitted to said receiving station through said video signal path on a time division manner after the establishment of the communication path.

Claim 4

A video monitoring system according to claim 2, wherein the video signal stored in said memory means is transmitted to said receiving station through said video signal path only when said receiving station makes a request for transfer of the video signal through said control signal path.

Claim 5

A video monitoring system according to claim 2, wherein the video signal stored in said memory means is transmitted to said receiving station through said video signal path unconditionally before the video signal is outputted from said pickup means and after the communication path is established between said sending and receiving stations.

Claim 6

A video monitoring system according to claim 2, wherein said receiving station includes a copying memory for copying and storing the video signal read out from said memory means and received through said video signal path, and supplies the video signal copied and stored in said copying memory to said monitoring means at any required point of time.

Claim 7

A video monitoring system according to claim 1, wherein said communication path includes a control signal path for transmitting a control signal to establish a logical connection between said sending and receiving stations and a video signal from said sending station to said receiving station when said sending and receiving stations are logically connected, the video signal outputted from said pickup means and the video signal stored in said memory means being transmitted to said receiving station through said video signal path on a frequency division manner after the establishment of the communication path.

Claim 8

A video monitoring system according to claim 6, wherein the video signal stored in said memory means is transmitted to said receiving station through said video signal path only when said receiving station makes a request for transfer of the video signal through said control signal path.

Claim 9

A video monitoring system according to claim 6, wherein the video signal stored in said memory means is transmitted to said receiving station through said video signal path unconditionally before the video signal is outputted from said pickup means and after the communication path is established between said sending and receiving stations.

Claim 10

A video monitoring system according to claim 6, wherein said receiving station includes a copying memory for copying and storing the video signal read out from said memory means and received through said video signal path, and supplies the video signal copied and stored in said copying memory to said monitoring means at any required point of time.

Claim 11

A video monitoring system according to claim 1, wherein said communication path comprises a control signal path for transmitting a control signal to establish a logical connection between said sending and receiving stations, and a first and second video signal paths for transmitting the video signal from said sending station to said receiving station when said sending and receiving stations are logically connected to each other; the video signal outputted from said pickup means after the establishment of said communication path being transmitted to said receiving station through said first video signal path, and the video signal stored in said memory means being transmitted to said receiving station through said second video signal path.

Claim 12

A video monitoring system according to claim 10, wherein said receiving station includes a copying memory for copying and storing the video signal read out from said memory means and received through said second video signal path, and supplies the video signal copied and stored in said copying memory to said monitoring means at any required point of time.

Claim 13

A video monitoring system comprising: a plurality of sending stations each for outputting a video signal indicative of an image of an object; a receiving station including monitor means for reproducing an image from the video signal; and a communication path selectively established between the plurality of sending stations and the receiving station to thereby monitor the video signal from a particular sending station through the monitor means when monitoring is required, wherein each of said sending stations comprises: pickup means for at all times picking up the image of the object and outputting the video signal indicative of the image; memory means for storing a video signal on the object corresponding to a particular event to be monitored, said memory means including a frame memory having a capacity to store an image signal of at least one field; sensor means for detecting the occurrence of the particular event to be monitored; first control means for storing in said memory means the video signal outputted from the pickup means in accordance with the detection of the occurrence of the particular event by said sensor means; and second control means for transmitting to the receiving station data on the identification of the sending stations selectively connected to the receiving station together with data on detection of the occurrence of the particular event by said sensor means, whereby after a communication path is established between a sending station and said receiving station, the stored video signal is read from said memory means and transmitted to said receiving station, and wherein said first control means puts said memory means in a write-enabled state in which the video signal outputted from said pickup means can be written at all times and, when said sensor means detects the occurrence of the particular event, said first control means puts said memory means in a write-disabled state to maintain the video signal already stored in said memory means.

Claim 14

A video monitoring system comprising: a plurality of sending stations each for outputting a video signal indicative of an image of an object; a receiving station including monitor means for reproducing an image from the video signal; and a communication path selectively established between the plurality of sending stations and the receiving station to thereby monitor the video signal from a particular sending station through the monitor means when monitoring is required, wherein each of said sending stations comprises: pickup means for at all times picking up the image of the object and outputting the video signal indicative of the image; memory means for storing a video signal on the object corresponding to a particular event to be monitored, said memory means including a frame memory having a capacity to store an image signal of at least one field; sensor means for detecting the occurrence of the particular event to be monitored; first control means for storing in said memory means the video signal outputted from the pickup means in accordance with the detection of the occurrence of the particular event by said sensor means; and second control means for transmitting to the receiving station data on the identification of the sending stations selectively connected to the receiving station together with data on detection of the occurrence of the particular event by said sensor means, whereby after a communication path is established between a sending station and said receiving station, the stored video signal is read from said memory means and transmitted to said receiving station, and wherein said first control means puts said memory means in a write-enabled state in which the video signal outputted from said pickup means can be written at all times and, when said sensor means detects the occurrence of the particular event, said first control means puts said memory means in a write-disabled state to maintain the video signal already stored in said memory means.

Claim 15

A video monitoring system according to claim 12, wherein said communication path comprises a plurality of control signal paths simultaneously established between the corresponding sending stations and the single receiving station for transmitting control signals therethrough and a video signal path selectively established when required for transmitting a video signal from said respective sending stations to said receiving station where said respective sending stations and said receiving station are logically connected to each other; and said second control means in each of said sending stations transmits data on the detection of the particular event and data on identification of that sending station through said the corresponding control signal path to said receiving station; and said receiving station further comprises: display means for visually displaying data on the identification of a sending station corresponding to the transmitted data on the detection of the particular event on the basis of the transmitted data; sending station selecting means for instructing the establishment of the video signal path between said receiving station and any particular sending station; and third control means for establishing the video signal path through said control signal path between said receiving station and said particular sending station, and fetching through the established video signal path the video signal outputted from said pickup means of said particular sending station and the video signal stored in said memory means by making a request for transmission of the video signals.

Claim 16

A video monitoring system according to claim 13, wherein said receiving station includes a copying memory for copying and storing the video signal read out from said memory means and fetched through said video signal path and said third control means inputs the video signal copied and stored in said copying memory to said monitoring means at any required point of time.

Claim 17

A video monitoring system according to claim 12, wherein said communication path comprises a plurality of control signal paths simultaneously established between the corresponding sending stations and the single receiving station for transmitting control signals therethrough and a first and a second video signal path selectively established when required for transmitting a video signal from said respective sending stations to said receiving station where said respective sending stations and said receiving station are logically connected to each other; and said second control means in each of said sending stations transmits data on the detection of the particular event and data on identification of that sending station through said the corresponding control signal path to said receiving station; and said receiving station further comprises: display means for visually displaying data on the identification of a sending station corresponding to the transmitted data on the detection of the particular event on the basis of the transmitted data; sending station selecting means for instructing the establishment of the video signal path between said receiving station and any particular sending station; and third control means for establishing the video signal path through said control signal path between said receiving station and said particular sending station, fetching through the first video signal path the video signal outputted from said pickup means of said particular sending station, and fetching through the second video signal path said the video signal stored in said memory means by making a request for transmission of the video signals.

Claim 18

A video monitoring system according to claim 15, wherein said receiving station includes a copying memory for copying and storing the video signal read out from said memory means and fetched through said video signal path and said third control means inputs the video signal copied and stored in said copying memory to said monitoring means at any required point of time.