System for a plurality of video cameras disposed on a common network

• US 7,576,770 B2
• Filed: 02/11/2004
• Issued: 08/18/2009
• Est. Priority Date: 02/11/2003
• Status: Expired due to Fees

• Current Assignee: e-Watch, Inc. (Cision Ltd.)
• Original Assignee: The Telesis Group, Inc.
• Inventors: Baird, John, Metzger, Raymond, Hollida, Ray, Alvarado, Adrian, Monroe, David
• Primary Examiner(s): Hannett; James M
• Assistant Examiner(s): KHAN, USMAN A
• Application Number:
  US10/776,129
• Publication Number:
  US 20060136972A1
• Time in Patent Office: 2,015 Days
• Field of Search: 348/47, 348/50, 348/139, 348/143, 348/201, 348/208.5, 348/211.11, 348705-706, 348/153, 348/156, 3482114-2118, 348/211.13, 348/159, 348/295, 725/105, 725/140, 725/1, 725/140.1
• US Class Current: 348/143
• CPC Class Codes: G08B 13/19645 Multiple cameras, each having view on one of a plurality of scenes, e.g. multiple cameras for multi-room surveillance or for tracking an object by view hand-over
• CPC Class Codes: G08B 13/19656 Network used to communicate with a camera, e.g. WAN, LAN, Internet
• CPC Class Codes: G08B 13/19689 Remote control of cameras, e.g. remote orientation or image zooming control for a PTZ camera
• CPC Class Codes: G08B 13/19697 Arrangements wherein non-video detectors generate an alarm themselves
• CPC Class Codes: G08B 25/006 Alarm destination chosen according to type of event, e.g. in case of fire phone the fire service, in case of medical emergency phone the ambulance
• CPC Class Codes: G08B 25/016 Personal emergency signalling and security systems emergency non-personal manually actuated alarm activators G08B25/12
• CPC Class Codes: H04N 21/21805 enabling multiple viewpoints, e.g. using a plurality of cameras
• CPC Class Codes: H04N 21/234363 by altering the spatial resolution, e.g. for clients with a lower screen resolution
• CPC Class Codes: H04N 21/2347 involving video stream encryption
• CPC Class Codes: H04N 7/181 for receiving images from a plurality of remote sources

Abstract

A plurality of cameras are adapted to utilize Ethernet network protocol for the physical layer and UDP/IP for the network and transport layers permitting multiple compressed signals representing different degrees of image resolution, compression type of compressed bit rate to be simultaneously transmitted. These multiple video streams may be combined into one composite stream for network transmission or may be maintained as separate and distinct video or still frame streams throughout the network. The digitizer, compressor and network interface can be integral to a camera or can be a separate unit. Video or images networked in this manner may be selective viewed on an operator console or may be received by a network server for storage, analysis and subsequent retrieval.

Claims

1. A surveillance system having a plurality of video cameras disposed on an Ethernet network and adapted for communicating with the ethernet network, the system comprising:

a plurality of cameras;

a digitizer of each camera, the digitizer being integral in a common housing with the respective camera;

a network interface for each camera, the network interface being integral in a common housing with the respective camera, the network interface being connected to the ethernet network;

each camera communicating with the ethernet network through the network interface;

a plurality of compressors integral in a common housing with each camera in advance of the network interface at each camera, each of the compressors outputting a respective compressed signal, the compressed signals each having at least one characteristic different from other of the compressed signals, the at least one characteristic being selected from among;

image resolution, compression type and compressed bit rate;

the network interface including an IP network stack, the IP network stack being configured to provide a plurality of IP data packets, the plurality of IP data packets conveying the compressed signals;

the camera including memory and a processor associated with the memory;

the camera including timestamp application software stored in the memory and executable upon operation of the processor, the timestamp application software when executed attaching presentation timestamps (PTS'"'"'s) in I-frame packets of the compressed signals;

a receiver adapted to be connected to the ethernet network to receive the compressed signals at a location remote from the camera, the receiver including;

memory;

a buffering software application stored in memory, the buffering software application including executable steps prescribing;

extracting presentation timestamps (PTS'"'"'s) from each of a series of received I-frame packets;

adding to extracted presentation timestamps (PTS'"'"'s) a time offset sufficient to account for worst case network delay, the extracted presentation timestamps (PTS'"'"'s) and time offset when added providing a series of respective sums;

a video player software application stored in memory, the video player software application when executed playing received compressed signals in series in relation to the sums;

a processor in communication with memory, the processor being operable to execute the executable steps; and

the receiver further including

the video player software application including a video player time base,

the video player time base providing a measure for pacing play of the received compressed signals;

the buffering software application including executable steps prescribing;

the time offset being a predicted delay value (delta T), the predicted delay value (delta T) initially being an estimate of worst case network delay, the extracted presentation timestamps (PTS'"'"'s) and predicted delay value (delta T) when added providing the series of respective sums;

substituting the respective sums for each presentation timestamp (PTS) to delay playback of each frame by the predicted delay value (delta T);

obtaining a local prediction of delay (local delta T) from the video player time base;

changing the predicted delay value (delta T) by a difference amount, the difference amount being calculated between the predicted delay value (delta T) and the local prediction of delay (local delta T) before adding the predicted delay value (delta T) to a next extracted presentation timestamp (PTS'"'"'s) extracted from the series of received I-frame packets.